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Hydrogenaudio Forum => Scientific Discussion => Topic started by: rick.hughes on 28 March, 2012, 06:59:33 AM

Title: Skeptoid: Digital vs Vinyl
Post by: rick.hughes on 28 March, 2012, 06:59:33 AM
Skeptoid: Digital vs Vinyl (http://skeptoid.com/episodes/4303)
Title: Skeptoid: Digital vs Vinyl
Post by: Fandango on 28 March, 2012, 04:29:49 PM
This thread just reminded me that I haven't listened to this episode yet! Actually I wanted to post about the episode here, too. But forgot about it.

What I can see from skimming through the transcript is that he doesn't go into all the technical details, i.e. the false claim that the dynamic range of vinyl goes beyond that of the CD is not technically refuted in all detail, if it was mentioned at all. edit: Now, that I've listened to it, I'm not so sure that vinyl and cd masters in the 80s were identical. But I have no clue actually, maybe someone can clarify that.

Nevertheless Skeptoid is really a great podcast, highly recommended. It's only ~10 minutes long so he can't get into much detail, but he still manages to pack it full with surprisingly rich content. Just look at the length of the transcripts.

But best of all is his persistence, Brian Dunning stoicly rips through every myth and conspiracy theory with ironclad scientific scepticism.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 28 March, 2012, 05:45:22 PM
Hmm, we shall see how he copes with my comment that points out the effects of distortion on bandwidth and loudness (as opposed to intensity).
Title: Skeptoid: Digital vs Vinyl
Post by: Fandango on 28 March, 2012, 10:38:52 PM
Didn't he dodge the big question anyway? He said that because the mediums are so different there's no point in ABX'ing them. I doubt he will challenge the theoretical limitations of the vinyl format. He simply claims it's inaudible and not ABX'able anyway, so it doesn't matter. The thing that I'm sceptical about is the first one, sure the effects of vinyl cannot be properly tested with actual vinyl because there are too many giveaways that have nothing to do with the way the format works, crackle, pops and noises feed into from the turntable for instance, but what one could do is simulate the theoretical physical limitations of vinyl records along with the post-production techniques digitally and take such processed samples and compare them to the same source samples treated as if they were produced for a CD. To answer the question he raises right from the start, if the limitations of vinyl alone are even audible, I think is doable, if one can eliminate all interfering factors, from the mics to the mastering and beyond.

Of course the results will hardly be applyable to the real world, because the overall real-world setups of vinyl listening and CD listening and the real-world preparations before each mediums are pressed are as he clearly pointed out too distinct from another.

I mean isn't it unscientific to claim one can do a proper ABX test between vinyl and CD under real-world conditions and say it is likely people can hear a difference because of how vinyl works and not because of all the other factors that also shape the sound that goes in a studio mic and come out a home speaker, them being different for vinyl and CD? Well, I would be very curious if the characteristics of vinyl playback can be simulated as a whole and whether it has been done before, maybe even just for certain aspects of the format.
Title: Skeptoid: Digital vs Vinyl
Post by: hlloyge on 29 March, 2012, 04:44:43 AM
I doubt he will challenge the theoretical limitations of the vinyl format.


Aren't those limits practical limits, not just theoretical? S/N, crackling, wow&flutter...?
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 29 March, 2012, 06:26:22 AM
I doubt he will challenge the theoretical limitations of the vinyl format.


Aren't those limits practical limits, not just theoretical? S/N, crackling, wow&flutter...?


Maybe the sense is that the practical limits of common hardware prevent you to reach the theoretical ones of the format?
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 29 March, 2012, 12:22:03 PM
Didn't he dodge the big question anyway? He said that because the mediums are so different there's no point in ABX'ing them. I doubt he will challenge the theoretical limitations of the vinyl format. He simply claims it's inaudible and not ABX'able anyway, so it doesn't matter. The thing that I'm sceptical about is the first one, sure the effects of vinyl cannot be properly tested with actual vinyl because there are too many giveaways that have nothing to do with the way the format works, crackle, pops and noises feed into from the turntable for instance,



In the real world, an LP doesn't necessarily acquire new crackles and pops and noises between playing it once to record it digitally, and playing it again to compare it to the digital copy.  So that is not necessarily a giveaway.
Title: Skeptoid: Digital vs Vinyl
Post by: Fandango on 29 March, 2012, 04:13:13 PM
Right, besides one could analyze the recording for such artefacts. In fact many aspects of vinyl playback can be analyzed and identified with software, or even simulated. But I dare think no-one has ever done an elaborate ABX test between vinyl and CDs where they have checked for vinyl playback giveaways. Would be interesting, even though I also have made my choice based on more practical reasons years ago.
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 29 March, 2012, 05:23:52 PM
In the real world, an LP doesn't necessarily acquire new crackles and pops and noises between playing it once to record it digitally, and playing it again to compare it to the digital copy.  So that is not necessarily a giveaway.


Although there are other causes for it, audible wow in record playback due to fluctuations in the platter's speed, will occur in random locations for each playback, so one couldn't even fairly ABX an LP to the same LP (a clone with identical pops/ticks) on the same model of turntable! There's a giveaway, at least for music where the wow might be audible. [Sustained piano chords and flute are often used to look for this.]

Synchronizing the two is also a nightmare, or an LP to a CD for that matter. So even if there are indeed no new pops or ticks on a second playing of an LP, the "giveaway" problem still exists.

What I'd do is the Meyer and Moran A/D/A loop trick  (http://www.aes.org/e-lib/browse.cfm?elib=14195)(where they compared SACD to their CD recorder's quick  A/D/A version of it); I would take the output of the LP and digitize it, but then bring it back to analog, almost instantaneously . This gets rid of the "giveaway" problems of subsequent LP playbacks due to all these factors. The wow (including flutter) components and the pops/ticks are the same, plus the two are synchronized.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 29 March, 2012, 09:01:29 PM
I doubt he will challenge the theoretical limitations of the vinyl format.


Aren't those limits practical limits, not just theoretical? S/N, crackling, wow&flutter...?


There is a theoretical limit to surface noise elimination on vinyl. It's not insubstantial, either.
Title: Skeptoid: Digital vs Vinyl
Post by: knutinh on 30 March, 2012, 02:36:26 AM
What I'd do is the Meyer and Moran A/D/A loop trick  (http://www.aes.org/e-lib/browse.cfm?elib=14195)(where they compared SACD to their CD recorder's quick  A/D/A version of it); I would take the output of the LP and digitize it, but then bring it back to analog, almost instantaneously . This gets rid of the "giveaway" problems of subsequent LP playbacks due to all these factors. The wow (including flutter) components and the pops/ticks are the same, plus the two are synchronized.

Or, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.

-k
Title: Skeptoid: Digital vs Vinyl
Post by: knutinh on 30 March, 2012, 02:55:01 AM
There is a theoretical limit to surface noise elimination on vinyl. It's not insubstantial, either.

Assuming that cost and impractical conditions does not pose theoretical limits, what is this based on?

If I was to make a "vinyl" record out of any concievable material, to be played back in strictly specified lab conditions, I would expect that the granularity (and mechanical "memory") of the atomic structure of that record to be the most fundamental limit?

I think that this presentation had some interesting background information on analog media degradation, funky italian-english aside:
http://www-dsp.elet.polimi.it/ispg/images/...tion_slides.pdf (http://www-dsp.elet.polimi.it/ispg/images/pdf/audio/materiale/restoration_slides.pdf)
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 30 March, 2012, 03:33:29 AM
Or, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.

-k

That way wouldn't be comparing direct analog LP sound to digital, though; it would be comparing two kinds of digital sound.
Title: Skeptoid: Digital vs Vinyl
Post by: greynol on 30 March, 2012, 10:56:53 AM
Ignoring CDDA, if you are attempting to suggest that high-res digital is unable to capture vinyl (or the master used to create it either before or after RMAA equalization was applied) 100% transparently, what is your basis for this?
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 30 March, 2012, 01:04:54 PM
Ignoring CDDA, if you are attempting to suggest that high-res digital is unable to capture vinyl (or the master used to create it either before or after RMAA equalization was applied) 100% transparently...

I'm not.
---

New topic for the general audience: I'm unable to read the original poster's link, because, at least through my browser/settings, when I click on it it brings me to a page that looks like I got the correct article, I think, however there seems to be many, many of the opening paragraphs (over a full page) completely obscured with a large, green table of contents starting with "About Skeptoid". If I click on any of the listings in it I still get this large, obscuring block, preventing me from seeing the actual page underneath. [Later, an invitation widow to subscribe also appears, however that I am easily able to close].

I don't really want to subscribe to skeptoid.com, but is that the only way to read the full article without this superimposed listing of articles? Or could some settings of my popup blocker, cookie blocking, or other settings be what's stopping me? I'm not well versed in how to deal with this sort of problem so any help would be appreciated. I am using Internet Explorer 9, if that matters.
Title: Skeptoid: Digital vs Vinyl
Post by: dhromed on 30 March, 2012, 03:13:27 PM
I'm unable to read the original poster's link, because, at least through my browser/settings [...] I am using Internet Explorer 9, if that matters.


Try Compatibility Mode. It should be a broken-page icon to the right of the address bar. Activating it will be remembered for the entire skeptoid.com website.

Failing that, you can hit F12, and a utility window will appear. The top bar of that particular window shows a menu button labeled "Browsermode: XYZ". Try selecting IE8 or IE7 from that menu. This is a one-time setting and will be forgotten when you navigate away.

If nothing seems to work, proceed to quietly mutter curses at IE, and download Firefox or Chrome, which should be a five-minute task.
Title: Skeptoid: Digital vs Vinyl
Post by: greynol on 30 March, 2012, 04:25:12 PM
I'm not.

That's good.  Perhaps it's only me, but I think sight has been lost on the target.

I feel the argument reverts to the inevitable, "as a delivery format, is there anything that vinyl can provide over CDDA that is audible to humans?"  Right now it appears that one can only answer yes when the the order of the two is reversed.
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 30 March, 2012, 04:28:43 PM
Dhromed, Thanks! Great respone, but when I went back to the site to try your suggestions,  it now loads just fine, as is! Maybe there was an oddity at their site the moment I had tried them before? Anyways, I wont complain any more, now that it works.
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 30 March, 2012, 07:38:15 PM
If I was to make a "vinyl" record out of any concievable material, to be played back in strictly specified lab conditions, I would expect that the granularity (and mechanical "memory") of the atomic structure of that record to be the most fundamental limit? ...


I have an extensive physical library of articles about the "vinyl" process. Being physical, it's hard to find things in it... Somewhere in it there is a quote which stuck in my mind, that at the highest recorded frequencies when the signal level approaches the noise level, the amplitude of the "wiggle" in the groove approaches the size of a hydrogen atom. I'll keep searching...
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 31 March, 2012, 05:18:57 PM
Although there are other causes for it, audible wow in record playback due to fluctuations in the platter's speed, will occur in random locations for each playback, so one couldn't even fairly ABX an LP to the same LP (a clone with identical pops/ticks) on the same model of turntable! There's a giveaway, at least for music where the wow might be audible. [Sustained piano chords and flute are often used to look for this.]


Good point.

Quote
Synchronizing the two is also a nightmare, or an LP to a CD for that matter. So even if there are indeed no new pops or ticks on a second playing of an LP, the "giveaway" problem still exists.

What I'd do is the Meyer and Moran A/D/A loop trick  (http://www.aes.org/e-lib/browse.cfm?elib=14195)(where they compared SACD to their CD recorder's quick  A/D/A version of it); I would take the output of the LP and digitize it, but then bring it back to analog, almost instantaneously . This gets rid of the "giveaway" problems of subsequent LP playbacks due to all these factors. The wow (including flutter) components and the pops/ticks are the same, plus the two are synchronized.


Identifying A vs B by 'before/after' switch comparison requires synchronization -- and that can work great.  But another way is to compare the same segment of A and B (resetting back to start at each switch), which one can do in foobar's ABX comparator, for example.  This is my preferred method of comparing short but 'telling' bits of audio.  It would be even more of a nightmare to apply to LP vs CD than synchronization -- and the wow/flutter problem would also pertain. ;>
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 31 March, 2012, 06:10:41 PM
Just want to point out that the biggest component of wow is decentering, and that will be consistent from play to play.

Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 31 March, 2012, 09:22:45 PM
But another way is to compare the same segment of A and B (resetting back to start at each switch), which one can do in foobar's ABX comparator, for example.  This is my preferred method of comparing short but 'telling' bits of audio.  It would be even more of a nightmare to apply to LP vs CD than synchronization...

Actually I think that method would be impossible. Foobar2000 has no analog incoming signal source option (that is, to be used as the  A or B signal) , as far as I know. Both A and B have to be digital files. Isn't that right? [I've only played around with it briefly.]

To do an ABX comparison using at least one purely analog medium, like LP, one would have to get a mechanical ABX comparator, like QSC's, or do manual swapping.

Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 03 April, 2012, 09:42:50 AM
I doubt he will challenge the theoretical limitations of the vinyl format.


Aren't those limits practical limits, not just theoretical? S/N, crackling, wow&flutter...?


Maybe the sense is that the practical limits of common hardware prevent you to reach the theoretical ones of the format?


Many of the limits are not due to the use of common hardware, but due to the fact that even the best hardware ever made couldn't do anything about them.

Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 03 April, 2012, 09:45:31 AM
Or, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.

-k

That way wouldn't be comparing direct analog LP sound to digital, though; it would be comparing two kinds of digital sound.


So what?

We already know from other experiments that reasonably good digital is sonically transparent, and the very best digital bests the thresholds of human hearing by orders of magnitude.
Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 03 April, 2012, 09:50:48 AM
Just want to point out that the biggest component of wow is decentering, and that will be consistent from play to play.


Agreed, which leads to the obvious question:

Since decentering is often the largest source of wow, and decentering is easy enough to reduce significantly by fairly simple mechanical means, why aren't all the vinylphiles doing that?

BTW, after decentering, its probably warps and warp wow induced by the tone arm that comes next.

Then there is the FM distortion caused by the interaction of bass and offset angled tone arms (IOW not straight line).

Same question.


Quote
Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.


Agreed, but again how many vinylphiles have transcribed their records to digital to eliminate that effect?  Probably a lot more LPs are transcribed for other reasons, many not even audible per se but rather related to convenience.
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 03 April, 2012, 12:31:33 PM

Maybe the sense is that the practical limits of common hardware prevent you to reach the theoretical ones of the format?


Many of the limits are not due to the use of common hardware, but due to the fact that even the best hardware ever made couldn't do anything about them.


Absolutely true! In fact upon reading again, I'd better used the term "real" in place of "common" (sorry for lexical imprecision from non English speaker. )

And speaking about analog sources, vinyl but tape as well, while what you precised holds true, it's true also that just because the tendency towards the theoretical limits is kind of asymptotic, on costs increase there could be an increase of perceivable musical performances. Now, it's not so difficult to understand why subjectivists and less technically educated music lovers are easily leaded to think that this same "cost vs performance curve" apply to digital sources too.
All the more, as normally analog performance increases come from visible mechanical improvements (heavier platters or capstans, lighter cartridges and shells etc...), the same people is easily fooled into thinking that better tangible built of an electronic device automatically means better musical performances!
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 03 April, 2012, 12:52:56 PM
Quote
Then there is the FM distortion caused by ............ offset angled tone arms (IOW not straight line).


That can be easily avoided:

(https://hydrogenaud.io/imgcache.php?id=adfb2548191ece16d7bc711dc9c0f417" rel="cached" data-warn="External image, click to view at original size" data-url="http://img22.imageshack.us/img22/79/td125dec06gall.jpg)
By kraut_2 (http://profile.imageshack.us/user/kraut_2) at 2009-03-27



Quote
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.

Where is the proof? Just claims pulled out of your behind?
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 03 April, 2012, 06:32:10 PM
Or, do a high-resolution digital recording of vinyl, play it back at high-resolution and CD-resolution in an ABX test.

-k

That way wouldn't be comparing direct analog LP sound to digital, though; it would be comparing two kinds of digital sound.


So what?

We already know from other experiments that reasonably good digital is sonically transparent, and the very best digital bests the thresholds of human hearing by orders of magnitude.


I dont think comparing two digital recordings will pass muster with the segment of vinylphiles who think there's something "better" about LPs than CD, in a comparison test they would agree is valid, at least. I suspect they would argue that one of the sources of the test actually be direct LP playback, not a recording of it we insist is "indistinguishably just as good to the human ear".

A well designed test should pass muster with people on both sides of the argument, not just one.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 04 April, 2012, 01:19:59 AM
Quote
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.

Where is the proof? Just claims pulled out of your behind?


Perhaps you should actually read up on the read mechanisms involved with contact stylii, and about plastic and elastic deformation in vinyl.

Your unnecessarily rude, inaccurate professional accusation aside, I am not making a statement that is in any way outside the arena of common knowlege of vinyl. If, for instance, you bother to read the AES collections on vinyl, you will find what you seek.
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 04 April, 2012, 10:59:53 AM
Quote
Perhaps you should actually read up on the read mechanisms involved with contact stylii, and about plastic and elastic deformation in vinyl.


Yes, I have done that enough over the last fifty years I play back vinyl.
The statement was done categorically - so who please is unprofessional here - without reference to cartridge mass, tracking weight, tracking angle (not existing in tangential arme, airbearing or motor driven) etc. etc. I for instance run wet, so some lubrication of the interface stylus/track walls is provided reducing friction.
Title: Skeptoid: Digital vs Vinyl
Post by: stephan_g on 04 April, 2012, 05:36:22 PM
Quote
Then there is the FM distortion caused by ............ offset angled tone arms (IOW not straight line).


That can be easily avoided:

(https://hydrogenaud.io/imgcache.php?id=adfb2548191ece16d7bc711dc9c0f417" rel="cached" data-warn="External image, click to view at original size" data-url="http://img22.imageshack.us/img22/79/td125dec06gall.jpg)
By kraut_2 (http://profile.imageshack.us/user/kraut_2) at 2009-03-27

To the best of my knowledge, linear trackers also have a non-zero (if constant) tracking angle since the cartridge has to drag the tonearm along. One would hope that those of the better kind used some kind of servo (à la power steering) to minimize both force and tracking angle, otherwise I'd imagine bearing friction would be extremely critical.

I'm awfully grateful for digital technology, that's for sure. It takes so many ifs and buts out of the equation it's not even funny. Just compare where a $150 record player and $150 CD player are on their respective diminishing returns scales in terms of output quality - absolutely no contest. Not to mention $50 DAPs and soundcards...
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 04 April, 2012, 08:45:56 PM
... To the best of my knowledge, linear trackers also have a non-zero (if constant) tracking angle since the cartridge has to drag the tonearm along. One would hope that those of the better kind used some kind of servo (à la power steering) to minimize both force and tracking angle, otherwise I'd imagine bearing friction would be extremely critical. ...


Many non-servo linear trackers use an air bearing (air is blown into the gap between the sleeve the tonearm is attached to, and the rod it slides on.) The arm platform has to be very precisely leveled, and the arm wires have to be carefully dressed (see the wires in the posted picture). For a good example of a servo powered integrated arm and turntable, consider the Technics SL-10 and SL-15.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 04 April, 2012, 10:50:20 PM
Quote
Perhaps you should actually read up on the read mechanisms involved with contact stylii, and about plastic and elastic deformation in vinyl.


Yes, I have done that enough over the last fifty years I play back vinyl.
The statement was done categorically - so who please is unprofessional here - without reference to cartridge mass, tracking weight, tracking angle (not existing in tangential arme, airbearing or motor driven) etc. etc. I for instance run wet, so some lubrication of the interface stylus/track walls is provided reducing friction.


Doesn't matter, the acceleration of the stylus is the issue.

Of course, you can make it a lot worse if you try.

Now, you've claimed expertise, eh? Mine is public knowlege, please show your fully and without doubt, and do so immediately.

I'll say it again, every play of vinyl causes some amount of damage unless you've got one of those laser turntables.
What's more, two plays in a row, with little time in between plays, is even worse.

I'm simply citing the known facts. You claim otherwise, well, show us your evidence.  Your claim is the extraordinary one, so you owe us extraordinary evidence.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 04 April, 2012, 10:53:44 PM
Many non-servo linear trackers use an air bearing (air is blown into the gap between the sleeve the tonearm is attached to, and the rod it slides on.) The arm platform has to be very precisely leveled, and the arm wires have to be carefully dressed (see the wires in the posted picture). For a good example of a servo powered integrated arm and turntable, consider the Technics SL-10 and SL-15.


Some force must be exerted, somewhere, in order to track, no matter how low the friction, because few, if any modern vinyl records have an absolutely constant pitch.

What's more, for something close to frictionless, we have some interesting issues in tracking bass in the L+R signal, I'd say. Of course, that system resonance is PROBABLY way below any such issue, so now we have to ask how it interacts with warpage, decentering, etc.

Physics works.
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 05 April, 2012, 02:59:40 AM
Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.


Not to mention that, more prosaically, every time you take a record out of its sleeve, no matter how careful you can be, that's a scratch waiting to happen... after that you will never get back the same signal!
Title: Skeptoid: Digital vs Vinyl
Post by: Engelsstaub on 05 April, 2012, 10:04:43 AM
...every time you take a record out of its sleeve, no matter how careful you can be, that's a scratch waiting to happen...


I find that about 1 out of 3 to 4 records I buy new today are already warped and/or have factory machine and handling marks right in the damned grooves. Sometimes I ask myself why I keep buying them.

I don't mind some surface noise and a few snaps every now and then. I don't even mind the seeming pain in the ass that vinyl is compared to CDs. What I do mind is paying more money for a record than the CD and getting a faulty or a defective product. The "limitations" of vinyl and clarity of a CD are of no consequence to me. I just want to collect and enjoy music.

...hard to enjoy music when it's pre-handled carelessly and sold for a premium. (CDs have stayed about the same in price since their inception.)
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 05 April, 2012, 12:55:01 PM
I find that about 1 out of 3 to 4 records I buy new today are already warped and/or have factory machine and handling marks right in the damned grooves. Sometimes I ask myself why I keep buying them.


It was ever thus (or at least, it was thus in the 1970s and early 1980s, my prime LP-buying days)
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 06 April, 2012, 01:28:33 AM
Quote
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.


I responded to this specific claim. He claims, he has to supply the proof. Not the other way round.

I never stated anything categorically as he did. I am fully aware that over many playbacks vinyl will gradually deteriorate. That's why I playback records wet and remove the residual moisture after playback.
I again ask - where is his proof other than in his anus?

Any measurements as to heat generation between stylus and vinyl at the contact surface? Any measurements of actual deforming happening at the stylus/vinyl surface interface? Any calculation as to the forces exerted by the stylus impacting the vinyl as to time and surface area involved and the resulting deformations, both  permanent and temporarily? All that in the lateral ant horizontal planes please.
Any differences between pivoted and tangential arms, differences between various tracking forces, raking angles VTA etc. Differences between cartridges of various compliance?
As you might have gathered from my question for proof: the categorical statements peddled are nonsense considering the parameters and possible variations involved.

As you point out - your knowledge is public - please demonstrate.

I have read over the years so many conflicting statements and so called research as to the topic of vinyl playback and stylus/medium impact that I doubt there is any conclusive statement to be made.
That is why ask for evidence, not idiotic statements.

Quote
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.


I find this claim absolutely hysterical in light of so many audiophile;e nonsense one has to contend with on other forums. It reminds me of the claims that everything will make a difference, be it shun mook discs, cryogenated cables, rhodium vs. gold plating etc.
Why is his statement not treated with the usual contempt and reference to TOS 8 or whatever number is applicable as to audibly tested evidence? I am asking not even for that - show me some fucking measurements.

And if you think my language is offensive - so be it, some statements do not deserve better than being severely offended against.
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 06 April, 2012, 02:37:11 AM
Quote
Where is the proof? Just claims pulled out of your behind?


My reply to an unproven assertion.

His response:
Quote
I'm simply citing the known facts. You claim otherwise, well, show us your evidence. Your claim is the extraordinary one, so you owe us extraordinary evidence.


Known? Where is the beef? Sounds very much like any audiophile statement I ever heard of. Where I did claim anything? I just asked for evidence and I have to supply evidence for a question? Any idea of scientific approach at all? Or how to treat requests - even impolite ones - for evidence? And on top playing the authority card? Any familiarity with skepticism?
Are you the pope of vinyl?
Quote
If, for instance, you bother to read the AES collections on vinyl, you will find what you seek.


Very arrogant and disingenuous, as almost all AES papers are behind a pay wall.

I am not sorry. I am an old grouch close to retirement and do not take to bull from whoever claims authority at face value any more. Show me the evidence and convince me, otherwise shut up.

I hardly ever play vinyl lately, relying on my server for playback, but I still do not accept unproven or undocumented claims from anybody about anything.
My experience in vinyl over 50 years have audible proven to me that records when well treated can play with only minor surface noise repeatedly for a long time; that is why I do not accept statements like the one I keep harping about with out supporting evidence.
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 06 April, 2012, 02:44:56 AM
Quote
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.


I responded to this specific claim. He claims, he has to supply the proof. Not the other way round. ...


Somewhere in my (paper) files I have a copy of a study performed in the early 80s that examined what happens to a played disc. It included observations on how long a groove takes to recover from the elastic deformation caused by playing. I can't remember the exact numbers, but I was surprised by how long it took. I haven't found the article yet, but while I was looking I did find something on wet playing:

... I playback records wet and remove the residual moisture after playback.


I found a report from a seminar presented by the Discwasher company, summarising the results of some two years of research into the interaction between vinyl disc records and pickup cartridges. Their research naturally included the effects of cleaning fluid.
" ... In one test, a 4 Khz test record was treated with de-ionised water and it was noted that there was a small increase in distortion; but after it had dried the distortion shot up by 20 to 25 dB - and similar results were had with an intermodulation distortion test record. Re-wetting the records brought the idstortion down again, but not to the original levels. Thus wet playing causes a permanent increase in harmonic and IM distortion.
For verification, records were wetted but not played and the eventual conclusion was that the water reacted with chemicals in the vinyl, causing a "puckering" effect. A more detailed explanation came from Dr. Bruce Maier (Discwasher principal), who put most of the blame onto stabilisers that are put into the record for anti-static and other reasons. One of these compounds is a co-polymer resin, vinyl acetate. This dissolves in water, but when it re-forms it makes hard ridges and bumps. I quote Dr. Maier: 'We postulated that acetic acid would be formed in this reaction, so we played the record twice - if the acid was there we thought it needed stirring before we could measure it. Lo and behold, the pH had increased 20 to 30 times. Once that acid is formed, it starts an automatic hydrolysis of the record surface. Now the record dries and spectral analysis reveals that these interfacial changes on the surface of the record cause a permanent puckering.'"

I'll keep looking for the deformation article. Only 11 folders to go...
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 06 April, 2012, 02:56:08 AM
And if you think my language is offensive - so be it, some statements do not deserve better than being severely offended against.


Yes, yes... but I do think you'd better save your offenses for more serious matters: here we're only chatting about fuck(... beep... ahem...    ) musical devices!
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 06 April, 2012, 03:12:28 AM
I play with a mixture with distilled water and 99% isopropyl alcohol (30% down mixed), and remove the liquid from the record surfaces immediately after playback is ended, removing any dirt, and eliminating static buildup.
Unfortunately the cited study was done by a company definitely not unbiased, with a stake in selling their particular product. So I have a problem trusting a study that runs contrary to my own experience over many many years, with the practices I employ.

This study reminds me too much of similar ones by various cable companies when citing skin effect (existing in any cable but completely irrelevant to audio) or capacitance to push their products publishing "white papers" (like white vans?)
Quote
Dr. Bruce Maier (Discwasher principal), who put most of the blame onto stabilisers that are put into the record for anti-static and other reasons. One of these compounds is a co-polymer resin, vinyl acetate.


The question is: as a copolymer it is not a freely available chemical, but bound in the polymer matrix. How reactive is it in this form at all? Again - another claim/blame without evidence?

Quote
Lo and behold, the pH had increased 20 to 30 times. Once that acid is formed, it starts an automatic hydrolysis of the record surface. Now the record dries and spectral analysis reveals that these interfacial changes on the surface of the record cause a permanent puckering.'"


That shows how "scientific" this so called Dr. is. An increase in pH does not means in increase in acidity, just the opposite. What an asshat....
This statement clinches this article for me: shilling for a company without even getting basic chemistry correct. Sounds like homeopathy....

Quote
but I do think you'd better save your offenses for more serious matters


What, you think audio is not a serious matter...where are your priorities, you question my life's purpose....who could you??
Title: Skeptoid: Digital vs Vinyl
Post by: greynol on 06 April, 2012, 03:23:09 AM
The topic at hand is not about the manner in which we are expressing ourselves. That said let's have a little more respect.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 06 April, 2012, 05:42:16 AM
Since I am not going to go buy an expensive, obsolete book in order to satisfy an individual's need to re-learn what is already understood in the art, I will simply cease participation in this thread.
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 06 April, 2012, 07:18:39 AM
I play with a mixture with distilled water and 99% isopropyl alcohol (30% down mixed), and remove the liquid from the record surfaces immediately after playback is ended, removing any dirt, and eliminating static buildup.


"Maier also fingered the alcohol base of some record treatments as a particular threat to the record's stabilizers." - Article in Billboard magazine, September 1980. (My original quotes were from a UK music magazine.)

Unfortunately the cited study was done by a company definitely not unbiased, with a stake in selling their particular product. So I have a problem trusting a study that runs contrary to my own experience over many many years, with the practices I employ.


Their research was done to identify causes of audible degradation from application of record cleaning or anti-static formulas, and formulate a product that minimised such damage. The point is that they did the research and produced actual figures and analyses, as well as being awarded several patents based on the work. Your supporting research for your assertion that it does no harm is... what?

The question is: as a copolymer it is not a freely available chemical, but bound in the polymer matrix. How reactive is it in this form at all? Again - another claim/blame without evidence?


It should be easy enough to prove by anyone with a chemistry education. The discwasher patents are available online, but I'm not a chemist. 

Quote
Lo and behold, the pH had increased 20 to 30 times. Once that acid is formed, it starts an automatic hydrolysis of the record surface. Now the record dries and spectral analysis reveals that these interfacial changes on the surface of the record cause a permanent puckering.'"


That shows how "scientific" this so called Dr. is. An increase in pH does not means in increase in acidity, just the opposite. What an asshat....


I would tend to place the blame on the reporter. "20 to 30 times" should have been a clue. He also said Maier was a physicist, whereas a former Discwasher employee says he was a biochemist:
http://www.audioasylum.com/mhtml/m.html?fo...vinyl&n=207 (http://www.audioasylum.com/mhtml/m.html?forum=vinyl&n=207)

I'm not saying you shouldn't wet play. I did it any time I found a disc with an intractable static or surface noise problem. I'm just pointing out that your belief that the practice is harmless is not supported by the facts.


Title: Skeptoid: Digital vs Vinyl
Post by: 2Bdecided on 06 April, 2012, 07:50:40 AM
My experience in vinyl over 50 years have audible proven to me that records when well treated can play with only minor surface noise repeatedly for a long time
I could say the same (though not quite so many years), but we humans are largely unable to detect small amounts of harmonic distortion. We're also bad at spotting small changes in anything that happen little-by-little over a large time frame, especially if we are there to see each stage of the change (e.g. a son we see every day doesn't seem to grow; a nephew we see once a year is seen to grow a lot each time).

For both reasons, our subjective judgement of how well records wear, especially from a time long before we digitised them to the time we finally digitised them, should be taken as the vague anecdote it is.

Taking a test record, digitising it, then intentionally wearing it out, would be a robust test. Though frankly, I'd only really want to know about preventable wear. Unpreventable wear that I otherwise won't notice is probably best not known about - like coding artefacts in content that I can only acquire via lossy source, it's better if I don't notice them, and better if I don't know they're there so I don't try to notice them or imagine I can hear them.

Cheers,
David.
Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 06 April, 2012, 09:52:02 AM
Quote
Then there is the FM distortion caused by ............ offset angled tone arms (IOW not straight line).


That can be easily avoided:

(https://hydrogenaud.io/imgcache.php?id=adfb2548191ece16d7bc711dc9c0f417" rel="cached" data-warn="External image, click to view at original size" data-url="http://img22.imageshack.us/img22/79/td125dec06gall.jpg)
By kraut_2 (http://profile.imageshack.us/user/kraut_2) at 2009-03-27



Quote
[Having said that, playing vinyl twice inside of a short period of time is bad for the vinyl and you will not get the same signal off the record.

Where is the proof? Just claims pulled out of your behind?


Well known problem - the vinyl groove is significantly distorted by the relatively high pressures at the point the stylus touches the groove, such that there is even a little pool of molten vinyl in there.

From AES paper:

"Role of Scanning Electron Beam Microscope in Disc Recording"

http://www.aes.org/e-lib/browse.cfm?elib=3080 (http://www.aes.org/e-lib/browse.cfm?elib=3080)

"Evidence of thc fact that vinyl melts can be found in pictures taken of record grooves played at different temperatures."

http://www.delback.co.uk/lp-cdr.htm (http://www.delback.co.uk/lp-cdr.htm)

"When you play an LP, the (hard) diamond stylus deforms the (soft) vinyl groove. When played normally (ie. dry), the friction causes the vinyl to heat up, which allows it to deform and return to its original shape after a while"
Title: Skeptoid: Digital vs Vinyl
Post by: DonP on 06 April, 2012, 09:54:42 AM
Lo and behold, the pH had increased 20 to 30 times.


Taking it from roughly neutral (7) to around 160?  I've never heard of anything that basic... no doubt it would dissolve right through stainless steel.

They didn't by chance mention 300 dBA speakers in the same article?
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 06 April, 2012, 03:23:16 PM
If you're a masochist there's always this 20-page thread (http://www.vinylengine.com/turntable_forum/viewtopic.php?f=19&t=22360&start=285) of vinylphiles debating virtues of wet LP play.  With math to prove it!
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 06 April, 2012, 03:49:15 PM
and, btw, the AES e-library is free to search.  Results are returned with abstracts.

e.g. 'vinyl' gets 293 hits, here's a few I foudn particularly interesting:

Quote
The Limiting Tracking Weight of Gramophone Pickups for Negligible Groove Damage

It has been observed that when spherical styli are dragged over flat vinyl surfaces, scratches are produced under loads considerably exceeding the elastic limit as calculated from theory. The author, in this paper, describes the results of his experiments which bear out his argument that under load the point of yield begins below the surface; and reaches the surface, producing visible tracks, only after the calculated yield load is exceeded. This critical value of load for styli of various radii has been measured and found to be equivalent to, for a 1-mil stylus, 0.64 gm. for a 90° record groove. No size or skin effect was found with the vinyl material tested.

Author: Barlow, D. A.
Affiliation: Aluminium Laboratories, Ltd., Banbury, Oxon., England
JAES Volume 6 Issue 4 pp. 216-219; October 1958


Quote
Groove Deformation and Distortion in Recordings

The elastic and plastic deformation of vinyl record compound under indenters of various profiles has been studied in large-scale tests. Curves of total depth of penetration versus load have been used to calculate the net distortion on record playback. In general, in the lower treble, net distortion is less, and in the upper treble, net distortion is greater than tracing distortion alone. This is important for attempts to reduce tracing distortion by inverse predistortion of the recorded signal. Nylon was also studied as a material with contrasting mechanical properties to vinyl. Further light has been shed on the nature of translation loss.

Authors: Barlow, Donald A.; Garside, Gerald R.
JAES Volume 26 Issue 7/8 pp. 498-510; August 1978


Quote
Comments on "On Stylus Wear and Surface Noise in Phonograph Playback System"
When a set of conclusions is reached in a study as fundamental as this, it is certain that particular factors have been accepted as a part of the working hypothesis essential to the formulation of conclusions which are open to challenge by another student of the subject. Mr. Barlow's studies, like those of Prof. Hunt, are thorough and represent another view of the same subject. Almost invariably, the points of departure in such cases become the focal points for study by all concerned. The process of further investigation usully results in the collection of additional test data that removes the subject from the realm of scientific speculation, and places it within the established body of knowledge of the art. Readers wishing to offer supporting or different viewpoints of their own for publication are invited to address them to the Editor. Such comments are especially welcome.

Author: Barlow, D. A.
JAES Volume 4 Issue 3 pp. 116-119; July 1956


Quote
Determination of Sliding Friction Between Stylus and Record Groove

A method is presented for determining the coefficient of sliding friction between stylus and record groove. The method consists of measuring the time intervals required for a freely rotating record (on a turntable) to decelerate from one known speed to another, both with and without a stylus sliding in the record groove. The method as been used to evaluate the frictional characteristics of several brands of phonograph records in mind condition and after treatment with various preservatives, cleaners, and antistatic agents. Some test results are presented
Author: Pardee, Robert P.
Affiliation: Ball Corporation, Aerospace Systems Division, Boulder, CO
JAES Volume 29 Issue 12 pp. 890-894; December 1981

.


Quote
Disc Record Care and Cleaning Accessories

Since the paper presented by me on a similar theme to the 50th AES Convention at the Cunard International Hotel in London in 1975, investigations into developments in this area have been pursued vigorously both in the UK and in other countries to tackle the problems of -record cleaning- and maintenance.

Author: Aldous, Donald
Affiliation: Hi Fi News and Record Interview, Plymouth
AES Convention:65 (February 1980)


Quote
An Investigation into the Increase of Non-Linear Distortion Products from Virgin Tape to Disc Playback

A study was carried out in order to examine the increase in distortion products arising from the various stages in the recording process from virgin tape, via tape copies, right up to and including interaction with specific record pick-up distortions. 1 kHz sinusoidal signals as well as some IM (400 + 4000 Hz) and double tone (9800 + 10200 Hz) signals were recorded at levels increasing in discrete 3 dB steps starting in non-critical range and continuing up to tape compression level. The tape -original- and first and second generation copies were then transcribed together onto 12" LPs. This made possible a study of the distortion progression and also the second and third order distortion combination products. The current practice of recording right up to the modulation limits of the tapes as well as of the disc seems to result in a total distortion percentage which considerably degrades the sound quality. In order to gain an impression of the audible effect of these distortions, some special musical samples were recorded with the same discrete level steps as the measuring signals. These musical samples were subjected to the same copying and transcription processes as the measuring signals and were similar in character (single tone, multi tone). Listening to these musical sample records provided an opportunity to establish perceptibility limits for the human ear regarding amounts of disturbing distortion.

Authors: Stephani, Otfried; Blüthgen, Björn
Affiliation: Polygram GmbH, Hanover, Germany
AES Convention:62 (March 1979) Paper Number:1453


Quote
An Experimental Study of Groove Deformation in Phonograph Records

Groove deformation has been analyzed in the literature primarily in terms of classical elasticity theory, which is based on assumptions that are not appropriate for stylus-groove contact. To determine the actual deformation-force relations, complex groove impedances have been measured as a function of tracking force, groove speed, etc. The results obtained are contrasted with classical predictions.

Author: White, James V.
Affiliation: Acoustics Research Laboratory, Harvard University, Cambridge, MA
JAES Volume 18 Issue 5 pp. 497-506; October 1970


Quote
Factors Affecting the Needle/Groove Relationship in Phonograph Playback Systems

It is shown that a phonograph pickup stylus riding in the groove of a record partly penetrates the groove walls because of elastic and plastic deformation of the record material. At high bearing loads complete plastic flow sets in and the needle leaves a permanent indentation track, while at lower loads the elastic deformation is predominant. This leads to amplitude distortion in the reproduced signal which may be of two types: one which is a function of the recorded wavelength (G function or translation loss), the other a function of the dynamic moving mass of the stylus/armature (H function or stylus/groove resonance). A third phenomenon (S function or scanning loss) is caused by the finite size of the stylus/groove-wall contact surface. Experiments with specially built pickups show the evolved theory to be valid even for very high frequencies. Special test records with recorded frequencies up to 100,000 Hz were used for these experiments.

Author: Bastiaans, C. R.
Affiliation: Westinghouse Research Laboratories, Pittsburgh, PA
JAES Volume 15 Issue 4 pp. 389-399; October 1967
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 06 April, 2012, 07:20:13 PM
Quote
To determine the actual deformation-force relations, complex groove impedances have been measured as a function of tracking force, groove speed, etc.


Quote
At high bearing loads complete plastic flow sets in and the needle leaves a permanent indentation track, while at lower loads the elastic deformation is predominant.


Exactly my contention versus categorical statements by those arguing from authority. Thanks.

It would be nice to know from the original paper what they found to be the tracking force where elastic deformation is dominant vs. permanent deformation.

Quote
I'm just pointing out that your belief that the practice is harmless is not supported by the facts.

I still play records wet with good results that I have owned and played back wet since the late sixties and early seventies.
If there is any harm, then it is offset by reducing problems with static, a record that is cleaned during playback etc.
It should also be mentioned that the development of heat during the playback is likely significantly reduced by a cooling agent, be it water alone or in a mix of alcohol (isoprop), thus further reducing the risk of permanent deformation.

Quote
Repeated playback (no matter what the timeframe) carries the risk of permanent damage. Obviously, records are observed to wear out with repeated play. No published evidence exists of back-to-back playback causing any more permanent damage than if repeated plays are separated by any longer period of time.


from the horses mouth itself: http://wiki.hydrogenaudio.org/index.php?ti...inyl_has_cooled (http://wiki.hydrogenaudio.org/index.php?title=Myths_%28Vinyl%29#The_vinyl_surface_is_heated_to_several_hundred_degrees_on_playback.2C_and_repeat_play_of_the_same_track_should_wait_at_least_several_hours_until_the_vinyl_has_cooled)

As to plasticizers in pvc:

I could not find any reference as to what plasticizers are used in PVC specifically for vinyl records. Or that Vinyl acetate was specifically used at all.

Quote
http://onlinelibrary.wiley.com/doi/10.1002...010508/abstract (http://onlinelibrary.wiley.com/doi/10.1002/pi.4980010508/abstract)


Quote
Polyvinyl chloride acetate (PVCA) is a thermoplastic copolymer of vinyl chloride and vinyl acetate.[1] It is used in the manufacture of electrical insulation, of protective coverings (including garments), and of credit cards and swipe cards.
http://en.wikipedia.org/wiki/Polyvinyl_chloride_acetate (http://en.wikipedia.org/wiki/Polyvinyl_chloride_acetate)


Quote
. The most common plasticizers are derivatives of phthalic acid. The materials are selected on their compatibility with the polymer, their low volatility, their low toxicity, and their cost.
http://en.wikipedia.org/wiki/Polyvinyl_chl...er_applications (http://en.wikipedia.org/wiki/Polyvinyl_chloride#Other_applications)

Quote
Copolymers of ethylene and vinyl acetate (E-VA) of a certain composition can be used for the improvement of impact properties (elasticisation) of PVC as well as under certain conditions (grafting) for the preparation of flexible PVC (plasticisation). Products of interesting properties are prepared by blending E-VA (up to ∼ 12%) with PVC or more advantageously by grafting vinyl chloride on special E-VA types. Graft copolymerisation by the suspension method allows the synthesis of E-VA/PVC systems in all ratios (up to 80% E-VA); these polymers are compatible over the whole range in contrast to the blends.

http://onlinelibrary.wiley.com/doi/10.1002...010508/abstract (http://onlinelibrary.wiley.com/doi/10.1002/pi.4980010508/abstract)
Quote
Plasticizers
It has been claimed that some plasticizers leach out of PVC products. However plasticizers do not readily migrate and leach into the environment from flexible vinyl articles because they are physically and tightly bound into the plastic as a result of the heating process used to make PVC particles.
http://en.wikipedia.org/wiki/Polyvinyl_chloride (http://en.wikipedia.org/wiki/Polyvinyl_chloride)


So again the study by the so called scientists by Discwasher seems to be more than flawed and not worthy any consideration imo.



Title: Skeptoid: Digital vs Vinyl
Post by: splice on 06 April, 2012, 09:14:59 PM
Quote
To determine the actual deformation-force relations, complex groove impedances have been measured as a function of tracking force, groove speed, etc.


It would be nice to know from the original paper what they found to be the tracking force where elastic deformation is dominant vs. permanent deformation.


The answer is in the first quote above: It Depends.
It depends on the stylus profile, cantilever mass, suspension compliance, room temperature, "groove speed", and the actual vinyl composition. 
As for figures, this area has been well studied. For example: "... we know that stylus pressure per square centimetre is on the order of tons, and that a permanent deformation of the groove is produced under static conditions. Dynamically, the values can vary by more than 12 tons/cm2, positive values causing defomation of the groove wall and negative values causing mistracking." - Jean Hiraga, 1978.
The best advice is to aim towards the maximum recommended tracking force given by the manufacturer of your stylus. Damage caused by high stylus pressure is less noticeable than damage caused by mistracking. I've found several articles in my files containing Scanning Electron Microsocope photos of groove damage caused by various mechanisms.

It should also be mentioned that the development of heat during the playback is likely significantly reduced by a cooling agent, be it water alone or in a mix of alcohol (isoprop), thus further reducing the risk of permanent deformation.


Most of the heat is produced inside the groove walls by the pressure of the stylus deforming the vinyl, not the friction of the stylus against the walls. The presence of a cooling agent has little effect.

As to plasticizers in pvc:

I could not find any reference as to what plasticizers are used in PVC specifically for vinyl records. Or that Vinyl acetate was specifically used at all.


For me, the evidence was that Discwasher found large quantities of acetic acid on the disc surface. Acetic acid is one of the precursors for vinyl acetate.
Apart from the Discwasher mention, there is:

Quote
... records are a complex chemical mixture including 85% polyvinyl chloride (PVC), 15% polyvinyl acetate (PVA), antistatic agents, dyes, stabilizers (heavy metals such as lead stearate), modifiers and lubricants. PVA, the exact chemistry of which varies among companies, both aids in the flow of vinyl during record pressing and as a plasticizer. Plasticizers play a critical role in softening the plastic/resin.

http://www.positive-feedback.com/Issue38/lp_sleaves.htm (http://www.positive-feedback.com/Issue38/lp_sleaves.htm)
I recommend this discussion for those interested in optimal storage of LPs. Also Wikipedia: http://en.wikipedia.org/wiki/Vinyl_disc_records_preservation (http://en.wikipedia.org/wiki/Vinyl_disc_records_preservation)

Quote
Plasticizers
It has been claimed that some plasticizers leach out of PVC products. However plasticizers do not readily migrate and leach into the environment from flexible vinyl articles because they are physically and tightly bound into the plastic as a result of the heating process used to make PVC particles.
http://en.wikipedia.org/wiki/Polyvinyl_chloride (http://en.wikipedia.org/wiki/Polyvinyl_chloride)

Proof that PVC plasticisers leach out with some alacrity is probably available in your own home, if you have plastic cables (equipment cables, mains extension cables) that have been in contact with acrylic painted surfaces. The plasticiser dissolves the paint and welds the cable and paint surface together, peeling the paint when the cable is moved. Also note that when you buy equipment with flexible leads and polystyrene packaging, the leads are packed in polythene bags. This isn't because it looks pretty, it's because the plasticisers also attack polystyrene.  Finally, PVC is no longer used in "cling film" food wrappng because the plasticisers were found to leach out into the food, especially foods containing fats.

So again the study by the so called scientists by Discwasher seems to be more than flawed and not worthy any consideration imo.


I think the last word of your sentence is the operative one. Facts are less partial.
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 06 April, 2012, 10:56:19 PM
Quote
Most of the heat is produced inside the groove walls by the pressure of the stylus deforming the vinyl, not the friction of the stylus against the walls. The presence of a cooling agent has little effect.


What does it matter where the heat is produced? If the groove wall gets deformed, the resultant heat will still be dissipated faster with a cooling agent present than without. And the cooling agent is in the groove after all. I do not understand your argument.

By your logic water surrounding a combustion motor cylinder will not help dissipate the heat because the heat is produced inside the cylinder?

Quote
For me, the evidence was that Discwasher found large quantities of acetic acid on the disc surface


Evidence by Discwasher is tainted, biased and therefore useless. Show me proper analysis of what is found with proper ph readings and I might be convinced. Other than that - hearsay.

Quote
including 85% polyvinyl chloride (PVC), 15% polyvinyl acetate (PVA), antistatic agents, dyes, stabilizers (heavy metals such as lead


I tried to find evidence concerning the composition of record grade vinyl, and could not find among the sources (several google pages) any that clearly defines what is included, even the one I linked to is fairly vague.
I looked into the chemistry of polymer vinyl acetate and some references were made to various products using this in conjunction with  chlorinated form of vinyl polymer, but no clear indication of its use.
The author linked to fails to supply any sources, so I will not accept his statements just now. The same goes for Wikipedia, no sources linked to support that statement.


Jean Hiraga, 1978: having read statements concerning tube amps by Hiraga, I have some difficulty accepting him as a serious source.

Quote
The plasticiser dissolves the paint and welds the cable and paint surface together, peeling the paint when the cable is moved


I have no experiential references to your statement.  I do not know what you are talking about.
The worst thing that I found regarding plasticizers is the deteriorating foam of old SLR cameras ( I collect pentax slrs, for use, not show) >40 years old.



Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 06 April, 2012, 11:16:10 PM
I have no experiential references to your statement.  I do not know what you are talking about.
The worst thing that I found regarding plasticizers is the deteriorating foam of old SLR cameras ( I collect pentax slrs, for use, not show) >40 years old.


IF we are to build knowlege, we must build on what others do that has been tested and verified, stuff like understanding that wet playing is hard on records, and that groves do deform due to accileration alone in vinyl playback.  It is, after all, despite your faux skepticism, nothing but physics.
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 07 April, 2012, 01:53:42 AM
I have no experiential references to your statement.  I do not know what you are talking about.
The worst thing that I found regarding plasticizers is the deteriorating foam of old SLR cameras ( I collect pentax slrs, for use, not show) >40 years old.


IF we are to build knowlege, we must build on what others do that has been tested and verified, stuff like understanding that wet playing is hard on records, and that groves do deform due to accileration alone in vinyl playback.  It is, after all, despite your faux skepticism, nothing but physics.


What bothers me with your posts is the categorical "knowing better" attitude, that apparently prohibits you from answering question other than by arguing from authority or flatly denying there is any benefit to the question in a fairly arrogant manner, called "besser wisser" in german.
The discussion regarding wet/vs dry playing is far from settled, and there are arguments for and against it, especially considering the claims regarding chemistry of vinyl that are far from certain and depend very much on each manufacturers formulation. We are not just talking physics here, we are talking chemistry and material science, complicating the issue.

The same is true for the deformation, elastic or otherwise that depends on the design of the tonearm, cartridge mass, tracking weight etc. If you want to ignore those parametres and how they change the actual wear and tear on a record - why do you even participate?  Just to piss on everybody else who has questions?
For me the "certain" claims as to behaviour are far from settled, as this discussion should show. We have contrary to questions like the non falsifiability of time dilation or even the calculations of the acceleration of mass in a gravitational filed no definite proof of any of your contentions regarding the material science, chemistry and its effect on the physical behaviour of a stylus on a record surface.

It is simply wrong just to categorically state that wet playing is "hard" on records, based on biased not very scientific research, ignoring the positive aspects.

But hey, why should you stop ignoring my arguments, you have been doing fine so far.

For some reason the name Sheldon comes to mind.....and thanks for the "faux" skeptic.
On other forums I participate in that would be equal to a Godwin....
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 07 April, 2012, 02:59:21 AM

Just a last note:
I know that my decades long experience with replaying vinyl "wet" is only considered anecdotal, but I have to my own satisfaction confirmed that the records I own for the last 45 - 40 years are still very playable, and that the not so fine grained spectrum displays both in foobar and the previously owned deq 2496 show me a frequency band that in good recordings  - well mastered - reaches from 20 Hz to at least 18 kHz, on a well used test record even almost ruler flat from 20 - 20 kHz on pink noise, despite some surface noise and the inevitable wow/flutter inducing some wobble of the display .

Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 07 April, 2012, 03:15:46 AM
The same is true for the deformation, elastic or otherwise that depends on the design of the tonearm, cartridge mass, tracking weight etc. If you want to ignore those parametres and how they change the actual wear and tear on a record - why do you even participate?  Just to piss on everybody else who has questions?


I didn't say to ignore anything, please tell the truth in the future.
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 07 April, 2012, 05:26:47 AM
... What does it matter where the heat is produced? If the groove wall gets deformed, the resultant heat will still be dissipated faster with a cooling agent present than without. And the cooling agent is in the groove after all. I do not understand your argument.


How fast the heat is dissipated doesn't affect the damaged caused. Take two identical discs. Play a blowtorch over them for a few seconds. Throw a bucket of water over one, leave the other to air cool. Which one suffers the most damage? It could also be argued that rapid cooling increases the stresses and damage to the vinyl, as it does to many other materials.

By your logic water surrounding a combustion motor cylinder will not help dissipate the heat because the heat is produced inside the cylinder?


Your logic is faulty. The combustion temperature in the cylinder will be the same whether there is a water jacket or not, just as the groove wall temperature reaches the same level whether wet played or not. Where your logic falls apart is when you count the number of cycles per second. Does a motor cylinder need water cooling if it only experiences one combustion cycle per 20 minutes or so?

Evidence by Discwasher is tainted, biased and therefore useless. Show me proper analysis of what is found with proper ph readings and I might be convinced. Other than that - hearsay.


Discwasher had to prove that the effect was real and that their product minimised it in order to obtain their patents. You, on the other hand, have only your own experience with no evidence. For example, your record collection is not duplicated, with one set played wet and one dry, with logging of the differences over the years.

Jean Hiraga, 1978: having read statements concerning tube amps by Hiraga, I have some difficulty accepting him as a serious source.


You appear to be unaware of his work on the interactions between the various parts of a turntable playing a record. It was well researched and mathematically rigorous. But it was uncontroversial and therefore unmemorable except to those working in the field. I learnt of his work after finding him quoted as a reference by later workers.

Quote
The plasticiser dissolves the paint and welds the cable and paint surface together, peeling the paint when the cable is moved


I have no experiential references to your statement.  I do not know what you are talking about.


Your lack of experience with a phenomenon does not mean it does not exist. The effect of PVC sheathed wiring on polystyrene foam is especially annoying to those who collect vintage gaming consoles and home computers. Those still with their original packaging are sought after, but all too often they were used and then packed away with the cables in contact with the polystyrene packaging popular at the time. The resulting damage lowers their value. As for the plasticisers in cling film, you can start here: http://en.wikipedia.org/wiki/Plastic_wrap (http://en.wikipedia.org/wiki/Plastic_wrap) and continue with the references at the bottom of the article.

The worst thing that I found regarding plasticizers is the deteriorating foam of old SLR cameras ( I collect pentax slrs, for use, not show) >40 years old.


I reluctantly retired my own SLR when the foam on the mirror frame disintegrated. Even after a thorough cleaning, occasional flecks kept appearing on the film so I couldn't trust it for critical work any more. Deteriorating foam has had a large effect on the audio scene as well. It's also a problem in the vintage mainframe and personal computer world, where foam was often used for sound deadening and air flow management.
Title: Skeptoid: Digital vs Vinyl
Post by: Engelsstaub on 07 April, 2012, 05:37:29 AM
...I recommend this discussion for those interested in optimal storage of LPs...


Thanks for those links, splice.

I've been following this (sometimes heated) discussion and find it interesting. I'm grateful for any good direction in preserving vinyl and getting the best out of it (or as good as reasonably possible.) I wish it were as easy as CDs

...anyway. Carry on.
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 07 April, 2012, 06:31:59 AM
Deteriorating foam has had a large effect on the audio scene as well.


Like in woofer suspensions disintegration which, AFAIK, in the long terms is caused much more by aging than by the mechanical stress of (reasonabily proper) playing.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 07 April, 2012, 04:36:22 PM
Deteriorating foam has had a large effect on the audio scene as well.


Like in woofer suspensions disintegration which, AFAIK, in the long terms is caused much more by aging than by the mechanical stress of (reasonabily proper) playing.



Yeah, I thought about pointing that out, but I don't think facts are the issue in this discusson.  I've had several older speaker designs I've done fail by foam-blowout. I'm sure I'm not the only one.
Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 08 April, 2012, 07:54:00 AM
and, btw, the AES e-library is free to search.  Results are returned with abstracts.

e.g. 'vinyl' gets 293 hits, here's a few I foudn particularly interesting:

Quote
The Limiting Tracking Weight of Gramophone Pickups for Negligible Groove Damage

It has been observed that when spherical styli are dragged over flat vinyl surfaces, scratches are produced under loads considerably exceeding the elastic limit as calculated from theory. The author, in this paper, describes the results of his experiments which bear out his argument that under load the point of yield begins below the surface; and reaches the surface, producing visible tracks, only after the calculated yield load is exceeded. This critical value of load for styli of various radii has been measured and found to be equivalent to, for a 1-mil stylus, 0.64 gm. for a 90° record groove. No size or skin effect was found with the vinyl material tested.

Author: Barlow, D. A.
Affiliation: Aluminium Laboratories, Ltd., Banbury, Oxon., England
JAES Volume 6 Issue 4 pp. 216-219; October 1958


Quote
Groove Deformation and Distortion in Recordings

The elastic and plastic deformation of vinyl record compound under indenters of various profiles has been studied in large-scale tests. Curves of total depth of penetration versus load have been used to calculate the net distortion on record playback. In general, in the lower treble, net distortion is less, and in the upper treble, net distortion is greater than tracing distortion alone. This is important for attempts to reduce tracing distortion by inverse predistortion of the recorded signal. Nylon was also studied as a material with contrasting mechanical properties to vinyl. Further light has been shed on the nature of translation loss.

Authors: Barlow, Donald A.; Garside, Gerald R.
JAES Volume 26 Issue 7/8 pp. 498-510; August 1978


Quote
Comments on "On Stylus Wear and Surface Noise in Phonograph Playback System"
When a set of conclusions is reached in a study as fundamental as this, it is certain that particular factors have been accepted as a part of the working hypothesis essential to the formulation of conclusions which are open to challenge by another student of the subject. Mr. Barlow's studies, like those of Prof. Hunt, are thorough and represent another view of the same subject. Almost invariably, the points of departure in such cases become the focal points for study by all concerned. The process of further investigation usully results in the collection of additional test data that removes the subject from the realm of scientific speculation, and places it within the established body of knowledge of the art. Readers wishing to offer supporting or different viewpoints of their own for publication are invited to address them to the Editor. Such comments are especially welcome.

Author: Barlow, D. A.
JAES Volume 4 Issue 3 pp. 116-119; July 1956


Quote
Determination of Sliding Friction Between Stylus and Record Groove

A method is presented for determining the coefficient of sliding friction between stylus and record groove. The method consists of measuring the time intervals required for a freely rotating record (on a turntable) to decelerate from one known speed to another, both with and without a stylus sliding in the record groove. The method as been used to evaluate the frictional characteristics of several brands of phonograph records in mind condition and after treatment with various preservatives, cleaners, and antistatic agents. Some test results are presented
Author: Pardee, Robert P.
Affiliation: Ball Corporation, Aerospace Systems Division, Boulder, CO
JAES Volume 29 Issue 12 pp. 890-894; December 1981

.


Quote
Disc Record Care and Cleaning Accessories

Since the paper presented by me on a similar theme to the 50th AES Convention at the Cunard International Hotel in London in 1975, investigations into developments in this area have been pursued vigorously both in the UK and in other countries to tackle the problems of -record cleaning- and maintenance.

Author: Aldous, Donald
Affiliation: Hi Fi News and Record Interview, Plymouth
AES Convention:65 (February 1980)


Quote
An Investigation into the Increase of Non-Linear Distortion Products from Virgin Tape to Disc Playback

A study was carried out in order to examine the increase in distortion products arising from the various stages in the recording process from virgin tape, via tape copies, right up to and including interaction with specific record pick-up distortions. 1 kHz sinusoidal signals as well as some IM (400 + 4000 Hz) and double tone (9800 + 10200 Hz) signals were recorded at levels increasing in discrete 3 dB steps starting in non-critical range and continuing up to tape compression level. The tape -original- and first and second generation copies were then transcribed together onto 12" LPs. This made possible a study of the distortion progression and also the second and third order distortion combination products. The current practice of recording right up to the modulation limits of the tapes as well as of the disc seems to result in a total distortion percentage which considerably degrades the sound quality. In order to gain an impression of the audible effect of these distortions, some special musical samples were recorded with the same discrete level steps as the measuring signals. These musical samples were subjected to the same copying and transcription processes as the measuring signals and were similar in character (single tone, multi tone). Listening to these musical sample records provided an opportunity to establish perceptibility limits for the human ear regarding amounts of disturbing distortion.

Authors: Stephani, Otfried; Blüthgen, Björn
Affiliation: Polygram GmbH, Hanover, Germany
AES Convention:62 (March 1979) Paper Number:1453


Quote
An Experimental Study of Groove Deformation in Phonograph Records

Groove deformation has been analyzed in the literature primarily in terms of classical elasticity theory, which is based on assumptions that are not appropriate for stylus-groove contact. To determine the actual deformation-force relations, complex groove impedances have been measured as a function of tracking force, groove speed, etc. The results obtained are contrasted with classical predictions.

Author: White, James V.
Affiliation: Acoustics Research Laboratory, Harvard University, Cambridge, MA
JAES Volume 18 Issue 5 pp. 497-506; October 1970


Quote
Factors Affecting the Needle/Groove Relationship in Phonograph Playback Systems

It is shown that a phonograph pickup stylus riding in the groove of a record partly penetrates the groove walls because of elastic and plastic deformation of the record material. At high bearing loads complete plastic flow sets in and the needle leaves a permanent indentation track, while at lower loads the elastic deformation is predominant. This leads to amplitude distortion in the reproduced signal which may be of two types: one which is a function of the recorded wavelength (G function or translation loss), the other a function of the dynamic moving mass of the stylus/armature (H function or stylus/groove resonance). A third phenomenon (S function or scanning loss) is caused by the finite size of the stylus/groove-wall contact surface. Experiments with specially built pickups show the evolved theory to be valid even for very high frequencies. Special test records with recorded frequencies up to 100,000 Hz were used for these experiments.

Author: Bastiaans, C. R.
Affiliation: Westinghouse Research Laboratories, Pittsburgh, PA
JAES Volume 15 Issue 4 pp. 389-399; October 1967



It appears to me that if Kraut just bothered to read the abstracts, he's sing a different tune!
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 08 April, 2012, 05:00:03 PM
It appears to me that if Kraut just bothered to read the abstracts, he's sing a different tune!


Well, if you read his stuff, he makes personal attacks, ignores facts, and focuses in on a few people.  My agenda detector kind of overheated there.
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 09 April, 2012, 01:08:14 AM
It appears to me that if Kraut just bothered to read the abstracts, he's sing a different tune!



Yes.  Point is, ANYONE could have done that search and got those results --  it's free.  The search terms was just 'vinyl'.

Had I posted all the results in chronological order from oldest to most recent, it would makes a fascinating historical record, well worth having a look at
for anyone at all interested in the history of vinyl and the transition from analog to digital.
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 09 April, 2012, 09:04:25 AM
I feel a sense of regret that the CD came along when it did. We were starting to make great strides in the science of vinyl reproduction - a deeper understanding of the physics in all areas from mastering to turntable design. What would the state of the art have become if vinyl had reigned another 10 years? And when a digital system finally did come along, it would almost certainly have a higher bit depth and sample rate. It might not even have been a disc - Soundstream prototyped a system with index-card sized media made of photographic film, with the bits recorded photographically, read by shining the laser through it. It would certainly have been cheaper to duplicate and easier to store.
Title: Skeptoid: Digital vs Vinyl
Post by: pdq on 09 April, 2012, 11:54:50 AM
@splice: That's an awful lot of conjecture, and frankly I see almost nothing that I would agree with.
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 09 April, 2012, 05:03:13 PM
@splice: That's an awful lot of conjecture, and frankly I see almost nothing that I would agree with.


We were indeed making great strides in vinyl technology in the 80s, and the Soundstream system was real. The remaining candidates for conjecture are my musings on sample depth and rate, and the possible physical carrier form. I look forward to hearing your reasons for disagreement. You can PM me if you prefer, and if it has legs we can open a thread for it.
Title: Skeptoid: Digital vs Vinyl
Post by: knutinh on 09 April, 2012, 05:44:46 PM
We were indeed making great strides in vinyl technology in the 80s, and the Soundstream system was real. The remaining candidates for conjecture are my musings on sample depth and rate, and the possible physical carrier form. I look forward to hearing your reasons for disagreement. You can PM me if you prefer, and if it has legs we can open a thread for it.

Blind tests have so far been unable to prove that 16/44.1 CD audio played from a $1 media on a really affordable player introduce any audible loss to 2-channel sound. Today, even this is becoming redundant, and files can be easily transmitted and streamed on the net with no local physical media.

Why should we strive for exotic systems if all they do is raise the price and make the hobby more elitist?

-h
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 09 April, 2012, 06:04:06 PM
@-h, I happen to agree with almost everything you wrote. Where I beg to differ is in the "striving for exotic systems". I believe we should strive, but not because it raises the price. Some people have the disposable income to indulge their desires to own exotic systems. Their investment pays for the R&D that eventually filters down to "affordable" systems.
Title: Skeptoid: Digital vs Vinyl
Post by: knutinh on 09 April, 2012, 06:28:08 PM
@-h, I happen to agree with almost everything you wrote. Where I beg to differ is in the "striving for exotic systems". I believe we should strive, but not because it raises the price. Some people have the disposable income to indulge their desires to own exotic systems. Their investment pays for the R&D that eventually filters down to "affordable" systems.

I dont believe that the world needs much more R&D on regular, high-bandwidth 2-ch playback. I don't believe that most such products contribute by a lot of "R", some seems to be pretty light on "D" as well.

I'd like to see more attention on the capture and rendering of spatially realistic audio and reference playback behaviour (absolute loudness, frequency response etc).

-k
Title: Skeptoid: Digital vs Vinyl
Post by: Engelsstaub on 09 April, 2012, 06:28:15 PM
My system is by no means exotic nor is it expensive. But I do have a Pioneer DVD player within it that is capable of playing DVD-A and SACD. I paid a little over a hundred bucks for it on Amazon.

I'm no audio-snob but I find the DVD-A capability useful. I can burn needle-drops (from my humble $500 dollar Pro-Ject TT) to cheap DVD-As and not even think or care about the bit-depth and sampling rate. Just enjoying music whatever the format.

I have to agree with splice: it would be cool if all formats were pushed to their full potential. IMO there's nothing wrong with erring on the side of more "sound quality" even if it does become inaudible to the average person.

It would also be great if we could do all of this without suffering ridiculous claims about audible sound quality and exotic hardware. ...balance

EDIT: knutinh also makes a great point which the timing of my post neglected to address.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 09 April, 2012, 11:58:07 PM
I'd like to see more attention on the capture and rendering of spatially realistic audio and reference playback behaviour (absolute loudness, frequency response etc).

-k


That, in a nutshell, is precisely the place where "stereo" falls light-years short.
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 09 April, 2012, 11:58:59 PM
"To determine the actual deformation-force relations, complex groove impedances have been measured as a function of tracking force, groove speed, etc. The results obtained are contrasted with classical predictions."
What are the results?

"It is shown that a phonograph pickup stylus riding in the groove of a record partly penetrates the groove walls because of elastic and plastic deformation of the record material. At high bearing loads complete plastic flow sets in and the needle leaves a permanent indentation track, while at lower loads the elastic deformation is predominant."
What I had said: deformation - elsatic vs. permanent depends on tracking weight.

"It has been observed that when spherical styli are dragged over flat vinyl surfaces..."
Has it occurred to anybody that a stylus point presents a different load to a flat surface than a stylus riding in a groove, the total load on the surface far from being a point load point load ?
"The method as been used to evaluate the frictional characteristics of several brands of phonograph records in mind condition and after treatment with various preservatives, cleaners, and antistatic agents. Some test results are presented"
What are the results?

"The elastic and plastic deformation of vinyl record compound under indenters of various profiles has been studied in large-scale tests. Curves of total depth of penetration versus load have been used to calculate the net distortion on record playback. In general, in the lower treble, net distortion is less, and in the upper treble, net distortion is greater than tracing distortion alone. This is important for attempts to reduce tracing distortion by inverse predistortion of the recorded signal. "
Again, what results and what are the parametres?

Having no access to the info, I am asked to accept vague abstracts as proof of what?

I am also bothered that attacks on statements, opinions and nondescript test results are seen as personal attacks. If that is the case, I really am in the wrong place here.


Title: Skeptoid: Digital vs Vinyl
Post by: greynol on 10 April, 2012, 12:07:20 AM
You may want to look up the word predominant.  I don't think it means what you think it means.
Title: Skeptoid: Digital vs Vinyl
Post by: Woodinville on 10 April, 2012, 12:28:48 AM
Having no access to the info, I am asked to accept vague abstracts as proof of what?


You demanded citations for the evidence counter to your mystical belief. You can pay to access the information. The burden of proof is entirely on your shoulders as is your vile defamation of those who have actually bothered to become informed.
Title: Skeptoid: Digital vs Vinyl
Post by: kraut on 10 April, 2012, 01:09:31 AM
Quote
as is your vile defamation of those who have actually bothered to become informed.


Thanks for your kind words.
I have no idea what the slander consists of, but I guess to raise questions is enough to invite such characterization.
I also appreciate the  friendly invite to spend 20$ per paper to access information that others refer to without actually citing specific results in most cases (except one as far as I recall).

As to predominant:
"pre·dom·i·nant
   [pri-dom-uh-nuhnt] Show IPA
adjective
1.
having ascendancy, power, authority, or influence over others; preeminent.
2.
preponderant; prominent: a predominant trait; the predominant color of a painting."

Which to me means elastic deformation is "preeminent" at an unspecified lower tracking weight

I think after that pleasant experience:
when asking questions and where the attack on statements - for sure not in the most pleasant manner - are being framed as "personal and now even "vile" attacks;
on a site that claims to be dedicated to evidence based claims where I think I am permitted to vigorously question postings and statements  that do not contain any specifics;
where I am asked to confirm for myself claims made by others without supporting data, to read up and pay for papers that are behind a paywall;
where it is ok for some to characterize postings and statements in a not very friendly manner but not by others (from my observation of the behaviour of mods and long term residents apparently a question of seniority)

I frankly think it is time to just walk away and in future mind my own business.
Title: Skeptoid: Digital vs Vinyl
Post by: knutinh on 10 April, 2012, 04:16:00 AM
I'd like to see more attention on the capture and rendering of spatially realistic audio and reference playback behaviour (absolute loudness, frequency response etc).

-k


That, in a nutshell, is precisely the place where "stereo" falls light-years short.

I've been a member here for some years. These discussions about minute differences between different stereo media never seems to end. Although it can be interesting to follow them due to the energy put into the science of perception as well as the art of debating, I think that the mind and time of those who choose to contribute could have been better spent elsewhere.

Common for these discussions all is that:
1. They usually cannot be confirmed using blind listening
2. When compared to the scale of modifications caused by recording technicians, loudspeaker (placement) etc, they tend to seem irrelevant

Compare this to the case with spatial reproduction. We know that humans can sense the direction of a sound source to within 5 degrees or 1 degree or something thereabout - in a sphere surrounding our head. No doubt further limited in many ways, this nevertheless suggests that sound reproduced over 2 loudspeakers in a room will never be anything but a crude approximation to most general soundfields encountered in real-life. The indeterminacy of the playback setup further means that the sound engineer have no accurate idea of what the playback really will sound like, and is therefore limited in the amount of "tricks" or "compensation" she can apply to the severe limitation that 2 channels represent.

We have all of this cheaply available dsp-power in our hands, and shelf-meters of science on perception. Instead of using this to improve listening experience in a significant way, we argue over audibility of stuff that is 40dB or 96dB below the signal, and playback mechanisms that are too fragile and cost-inefficient to ever become sensible mainstream audio playback systems.

-k
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 10 April, 2012, 05:56:11 AM
We know that humans can sense the direction of a sound source to within 5 degrees or 1 degree or something thereabout - in a sphere surrounding our head. No doubt further limited in many ways, this nevertheless suggests that sound reproduced over 2 loudspeakers in a room will never be anything but a crude approximation to most general soundfields encountered in real-life.


True in general, but every "real life" musical experience comes from musical sources in front of the listener, unless you want to reproduce the player's own experience, so the two channel approximation all in all is not so crude.
Title: Skeptoid: Digital vs Vinyl
Post by: knutinh on 10 April, 2012, 06:52:01 AM
True in general, but every "real life" musical experience comes from musical sources in front of the listener, unless you want to reproduce the player's own experience, so the two channel approximation all in all is not so crude.

I shall stop my offtopic contribution with this post. Perhaps this discussion should be split into a separate thread.

Unless you are trying to simulate the acoustics of an anechoic chamber, and you are also listening in an anechoic chamber, I believe that:
1. The soundfield that you are trying to emulate will include energy from practically all directions (although at highly different levels)
2. The signal coming from your amplifier will be altered by the loudspeakers and room to come from practically all directions (although at highly different levels)

The problem is that 1. and 2. will usually deviate from one another in complex, perceptually significant ways (my claim). The concert hall might include desirable late-arriving significant reflections from side-walls to your left and right (difficult to record and distribute), while the listening room might include an undesirable, significant reflection from the wall directly behind you (difficult to suppress). The individual pipes of an pipe organ will both have a different direct path to your head, and interact with the reverbrant room in somewhat different ways. The end-result is that the sound that reach your ears is "spatially complex", and I believe that there is sufficient evidence that humans have (at least) the low-level sensory aparatus to appreciate such differences. This is in contrast to e.g. energy > 20kHz where evidence of perception is very scarce to say the least.

I think it is reasonable to speculate that "spatial accuracy" is the single largest perceptual audiological flaw in "state-of-the-art" reproduction of acoustic music, perhaps the only. I.e. what cause listeners to perceive the difference between "being there" in a concert hall, and listening to commercial recordings of the same event, when all senses and biases except hearing is excluded.

-k

edit:
Most pop-music is produced with goals different from that of reproducing a real acoustic performance. I think my point still stands: people will be able to perceive more spatially "rich" rendering than we usually have today, and pop music producers might want to exploit this space to do creative stuff (http://en.wikipedia.org/wiki/Amused_to_Death). But the reproduction chain from studio to listener severly limits them from doing so.
Title: Skeptoid: Digital vs Vinyl
Post by: pdq on 10 April, 2012, 07:54:40 AM
Say what you will about two channels, but I grew up in the age of mono, and the first time I heard stereo I was blown away.
Title: Skeptoid: Digital vs Vinyl
Post by: pdq on 10 April, 2012, 10:44:17 AM
@splice: That's an awful lot of conjecture, and frankly I see almost nothing that I would agree with.


We were indeed making great strides in vinyl technology in the 80s, and the Soundstream system was real.

I don't have any details on the Soundstream system of recording audio data optically on a card, but let's muse on that a little.

A CD has a data track that is over 5,000 meters long by 1.6 micrometers wide. It is scanned at a rate of about 1.2 meters per second. The disc is about 1 mm thick so that a lens that is almost in contact with it can have a very short focal length and very small f/ number. Without that it would not have enough resolution at the wavelength available in early 1980's diode lasers to resolve 1.6 micron details.

Now what would be the equivalent in a "card"? To have the same storage area as a CD it would need to be about 8x10 cm. To be able to read the data with the same inexpensive diode laser you would still need to have the lens almost in contact with the card, but now you are scanning the data rectilinearly, i.e. scan one axis very rapidly while tracking the other axis within 1.6 microns. To achieve 1.2 meters per second scanning you would need to scan the long axis 12 times per second back and forth. Does any of this actually sound like a viable alternative to CD?

If someone has real information on how the Soundstream system worked I would love to hear it. Perhaps they had some approach that I have not thought of that made it all practical, but after all, their product was never introduced and shortly after they went out of business.

Edit: I searched for Soundstream's patents, and none that I found related to optical storage of audio data. Apparently they didn't value the idea very highly.
Title: Skeptoid: Digital vs Vinyl
Post by: DonP on 10 April, 2012, 11:18:48 AM
True in general, but every "real life" musical experience comes from musical sources in front of the listener, unless you want to reproduce the player's own experience, so the two channel approximation all in all is not so crude.


Ambiance of the venue aside, you can distinguish between live performances where the sound is coming directly from each performer's instrument and/or mouth, and those where it all comes from a speaker or stack on either side of the stage.

I have heard some very engaging 5.1 concerts where the rears had some music reflections, but the surround was mostly audience sound.

Title: Skeptoid: Digital vs Vinyl
Post by: lvqcl on 10 April, 2012, 11:39:59 AM
Don't know about Soundstream... found this: http://www.aes.org/aeshc/docs/aeshist/stan...ds/jaes29-1.pdf (http://www.aes.org/aeshc/docs/aeshist/standards.hist/digital.standards/jaes29-1.pdf)

Quote
JVC AHD DIGITAL AUDIO DISK SYSTEM:

Pickup method: Grooveless electro-tracking capacitance pickup system
Disk size: 260 mm (10 in)
Revolutions: 900 r/min, the same in PAL and SECAM countries
Playing time: 2 hours (1 hour per side)
Number of channels: 4 (3 audio channels and 1 still-picture channel)
Quantization: 16 bit linear
Sampling rate: 47.25 kHz
Picture transmission method: Digital
Title: Skeptoid: Digital vs Vinyl
Post by: Nessuno on 10 April, 2012, 01:09:53 PM
I shall stop my offtopic contribution with this post. Perhaps this discussion should be split into a separate thread.


I keep answering here, but yes, if a mod could fork another thread, that would be better.


Quote
Unless you are trying to simulate the acoustics of an anechoic chamber, and you are also listening in an anechoic chamber,


Well, I think a main point here is deciding if a musical recording is intended to be a mere reproduction of the whole sonic event or rather a media to deliver the artistic content of the event itself.
I lean toward this latter meaning, so the idea of an event recorded and reproduced in anechoic chambers is not so far from what I expect from an ideal recording, be it live or studio (BTW: for this reason I do like near field listening): every "non musical" content, like poor auditorium acoustic treatment, large cathedral reverberations etc... must be, as much as possible, avoided. Under this point of view, which is of course a subjective one, a stereophonic rendering is always an approximation (no vertical and limited depth resolution) but not such a bad one and worth devoting further researches. Miking and mixing techniques on one side, room treatment and most of all, speaker placement on the other can do wonders!


Quote
Most pop-music is produced with goals different from that of reproducing a real acoustic performance. I think my point still stands: people will be able to perceive more spatially "rich" rendering than we usually have today, and pop music producers might want to exploit this space to do creative stuff (http://en.wikipedia.org/wiki/Amused_to_Death). But the reproduction chain from studio to listener severly limits them from doing so.


This is more related to the ways an artist could find to express his aesthetic choices and how he is able to master and overcome technical limitations which are inherent in every tool he could use. But it would be an act of artistic creation: if a composer feels like using a surround multichannel system, which already exists, as part of his artistic work, then that system will become a tool required to perform and reproduce it. And maybe as long as other artists will embrace this movement, more surround systems will enter music fan homes.

All that said, using surround to help me better localize that coughing one two rows behind and five seats right… no, thanks!
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 10 April, 2012, 04:54:33 PM
... If someone has real information on how the Soundstream system worked I would love to hear it.  ...


There was a multi-page article in, I think, HFN&RR back in the 80s. I'll get the publication date if you want. After reading your theorising on how it worked, you need to prepare for a paradigm shift... 3 lasers and pickups, mounted 120 degrees apart on spinning discs, facing each other. The film card travelled between them, mounted on a leadscrew driven carrier. The data was recorded in an arc across the card. As one head left the card at one edge, the next head was starting to read at the other edge. I never found any explanation why they didn't pursue it, but I suspect it may have been too hard to "productionise" the tolerances needed to harmonise the tracking of the 3 heads. It would be a lot easier with current electronics (one head and a buffer), but now film technology is going away...
Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 11 April, 2012, 11:14:14 AM
If someone has real information on how the Soundstream system worked I would love to hear it. Perhaps they had some approach that I have not thought of that made it all practical, but after all, their product was never introduced and shortly after they went out of business.


Wikipedia Soundstream article (http://en.wikipedia.org/wiki/Soundstream)

Check the last 2 footnotes...
Title: Skeptoid: Digital vs Vinyl
Post by: splice on 16 April, 2012, 09:47:38 PM
I doubt he will challenge the theoretical limitations of the vinyl format.


Aren't those limits practical limits, not just theoretical? S/N, crackling, wow&flutter...?


Maybe the sense is that the practical limits of common hardware prevent you to reach the theoretical ones of the format?


Jim LeSurf did some work in the trackability area, examining the theoretical limits and the limits used in practice.
My apologies if you've seen them before. I don't think they've been quoted in HA recently. 

http://www.audiomisc.co.uk/HFN/LP1/KeepInContact.html (http://www.audiomisc.co.uk/HFN/LP1/KeepInContact.html)
http://www.audiomisc.co.uk/HFN/LP2/OnTheRecord.html (http://www.audiomisc.co.uk/HFN/LP2/OnTheRecord.html)
http://www.audiomisc.co.uk/HFN/LP3/aroundthebend.html (http://www.audiomisc.co.uk/HFN/LP3/aroundthebend.html)
http://www.audiomisc.co.uk/HFN/LP4/NewLampsForOld.html (http://www.audiomisc.co.uk/HFN/LP4/NewLampsForOld.html)

Title: Skeptoid: Digital vs Vinyl
Post by: pdq on 17 April, 2012, 08:34:40 AM
Only in the world of vinyl would 1% THD be referred to as "excellent".
Title: Skeptoid: Digital vs Vinyl
Post by: Arnold B. Krueger on 17 April, 2012, 08:43:58 AM
Only in the world of vinyl would 1% THD be referred to as "excellent".


Umm, 1% THD is also cosidered to be excellent in the world of loudspeakers.

Under some conditions 10% THD is considered both excellent and acceptable for a loudspeaker.
Title: Skeptoid: Digital vs Vinyl
Post by: Pio2001 on 15 September, 2012, 11:45:21 AM
But I dare think no-one has ever done an elaborate ABX test between vinyl and CDs where they have checked for vinyl playback giveaways. Would be interesting, even though I also have made my choice based on more practical reasons years ago.


Hello guys,
For what it's worth, I have a small collection of samples recorded from vinyl and ripped from CD, that are time and level-aligned in order to allow a comparison, or atleast to listen to the specific distortions of vinyl, recorded into digital files.

In this listening test, some samples from the same songs come sometimes from vinyl vs CD, sometimes from different pressings of the same vinyl, sometimes from different masters. Several intersting cases are present.
Here is the link : http://www.hydrogenaudio.org/forums/index....showtopic=37328 (http://www.hydrogenaudio.org/forums/index.php?showtopic=37328)
The result were only published in French, there : http://forum.hardware.fr/hfr/VideoSon/HiFi...jet_87812_1.htm (http://forum.hardware.fr/hfr/VideoSon/HiFi-HomeCinema/resultats-comparatif-vinyle-sujet_87812_1.htm)
But if you need some clarification in English, just ask me.

It features a total of 8 pairs of samples, plus one set of 4 ones from various sources. 14 people downloaded and commented them. All were invited to ABX them. Indeed, all pairs were easily ABXable, except one that is only ABXable with some concentration.


Besides this test, here is a more specific pair of samples :

http://3141592.pio2001.online.fr/files/vin...speed-level.wav (http://3141592.pio2001.online.fr/files/vinyletest/Final2680-speed-level.wav)
http://3141592.pio2001.online.fr/files/vin...trackmaster.wav (http://3141592.pio2001.online.fr/files/vinyletest/final2trackmaster.wav)

The same record, taken from two different turntables, with two different stylii. The samples are speed-corrected (turntable speeds didn't match), level-aligned, and equalized (the cartridges had a different frequency response). The goal was to listen to a specific distortion that might be related to stylus wear, of maybe tonearm quality, I don't know. The distortion was present in one of the two playback setup, and I wanted to ABX it. It's the same kind distortion that you hear at the end of a 33 rpm side when chorus or organ is recorded, except that here, we can hear it caused by the playback equipment.
It seems easy to hear in non blind conditions, however, succeeded this ABX test was a challenge for me. But I did it. There is indeed more distortion in the Trackmaster file. It took me a lot of time and effort to spot it, but once I did, the ABX suddenly became a piece of cake.


Here are six isolated samples. I selected them long ago in order to illustrate the surface noise of vinyls in the most common conditions. Just in case someone was curious.

http://3141592.pio2001.online.fr/files/vin...ise/33clean.mpc (http://3141592.pio2001.online.fr/files/vinylnoise/33clean.mpc)
An example of high quality 33 rpm record. The label was EyeQ, and their releases, though aimed at DJ's, were always top quality.

http://3141592.pio2001.online.fr/files/vin...ise/average.mpc (http://3141592.pio2001.online.fr/files/vinylnoise/average.mpc)
The average surface noise of a clean LP. The recording level is similar to the other samples, it's just that this part of the music is quiet.

http://3141592.pio2001.online.fr/files/vinylnoise/bad.mpc (http://3141592.pio2001.online.fr/files/vinylnoise/bad.mpc)
An example of poor quality, but brand new LP. It was not uncommon to get new records with that amount of noise.

http://3141592.pio2001.online.fr/files/vin...ise/defects.mpc (http://3141592.pio2001.online.fr/files/vinylnoise/defects.mpc)
Two examples of defective records. Both from the 1990's.

http://3141592.pio2001.online.fr/files/vinylnoise/occaze.mpc (http://3141592.pio2001.online.fr/files/vinylnoise/occaze.mpc)
An example illustrating the average noise of an LP bought second hand.

http://3141592.pio2001.online.fr/files/vinylnoise/worn.mpc (http://3141592.pio2001.online.fr/files/vinylnoise/worn.mpc)
An example of good quality record (bought second hand, btw), that has been played tens and tens of times.


Last, I have got a very special test, of little interest. I recorded two times the same record with the turntable just in front of the speaker. One time with the speaker off. One time with the sound at full power directed right on the cartridge. I wanted to test the claim that feedback from the speakers was a plague for sound quality, and that a Larsen loop was even possible.

http://3141592.pio2001.online.fr/files/vin...ithfeedback.mpc (http://3141592.pio2001.online.fr/files/vinylfeedback/withfeedback.mpc)
http://3141592.pio2001.online.fr/files/vin...outfeedback.mpc (http://3141592.pio2001.online.fr/files/vinylfeedback/withoutfeedback.mpc)

No Larsen. Nothing. I can't even ABX them !
Title: Skeptoid: Digital vs Vinyl
Post by: hlloyge on 15 September, 2012, 02:09:13 PM
Last, I have got a very special test, of little interest. I recorded two times the same record with the turntable just in front of the speaker. One time with the speaker off. One time with the sound at full power directed right on the cartridge. I wanted to test the claim that feedback from the speakers was a plague for sound quality, and that a Larsen loop was even possible.

http://3141592.pio2001.online.fr/files/vin...ithfeedback.mpc (http://3141592.pio2001.online.fr/files/vinylfeedback/withfeedback.mpc)
http://3141592.pio2001.online.fr/files/vin...outfeedback.mpc (http://3141592.pio2001.online.fr/files/vinylfeedback/withoutfeedback.mpc)

No Larsen. Nothing. I can't even ABX them !


Well, I had a tape of recorded from vinyl Kraftwerk album, The Man Machine, with the sound of some acid house in the distant background, almost at the noise level - you could hear it while listening with headphones on the quiet parts. Tape was new, unsealed, Type2 TDK SA.
Friend who taped me that said he was recording and listening quite loudly to some house CDs.
That was in late 80's. I can't abx that, because this tape doesn't exist anymore, as I bought Kraftwerk albums on CDs in the mean time...
And FYI, I'm not audiophile in the means that I need expensive gear to enjoy music - I'm more of an musicfile, gear has to be adequate so I can recognize the instruments...
Title: Skeptoid: Digital vs Vinyl
Post by: Pio2001 on 15 September, 2012, 02:31:52 PM
Yes, that is something that I noticed too. Never listen to something else while you record a vinyl ! But it seems that either this kind of feedback is harmless if the signal is the record itself, or some turntables are more sensitive than others. The one used for the feedback test was a Technics SL-3100.
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 15 September, 2012, 07:57:35 PM
On some receivers/preamps the record out selector (or just input selector) doesn't have perfect isolation between inputs, there is electrical bleed through -[just like the L and R ch also sometimes bleed through to each other], even if those other inputs aren't being listened to. On receivers this can particularly be a problem since you can't really turn off the tuner section on many, it is always "on" even if no frequency is displayed. The best you can do is tune to dead air and/or disconnect the antenna, if it is a problem.
---

On turntables acoustic feedback is often via vibration from the resting surface and not via sound waves through the air. If one were to want to induce it, try placing the turntable on the (full range) speaker and defeat (if possible) the phono preamp's subsonic filter.

In its extreme form it will make a loud howling noise, just like stage mics are known to, however it also can subtly color the music at lower levels. The effect is subtle and easily masked in many situations. Turntables with good vibration isolation, such as ones with a floppy, floating sub-chassis (keeping the arm and platter suspended in their own separate world, without a direct connection to the plinth), are typically immune to this problem, in fact that is why they are made this way.
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 16 September, 2012, 01:22:24 PM
For us non-Francophones, here's Google Translate's attempt of the Conclusion.  Some bits are less comprehensible than others ;> 



Quote
We found that the difference between vinyl and CD can be heard on digital copy, which is not surprising, vinyl does not have perfect sound.
More surprisingly, the greatest differences are not always found between CD and vinyl (RMB, bad press), but also a vinyl to another (Depeche Mode - A Question of Lust), and even throughout another of the same vinyl (Legendary Pink Dots - Pennies for Heaven / Evolution).
 
Among other differences, the differences in balance bass / treble are important. They vary from one disk to another, from one label to another (the German distributor of Depeche Mode, Intercord, produces vinyl still missing treble), but always returns a trend: these excerpts vinyl have more serious (about 50-100 Hz), and less acute (around 3000 - 12000 Hz) than their counterparts in CD. Cete trend can not be attributed to the recording chain. This is a characteristic of the cell used to read the disc: Stanton Trackmaster EL one. Phonolectrices cells have very different response curves, which determine a large part of their "tonal color."
The CD has the merit to linearize the response curve, very unstable vinyl.
 
It begs the question of whether these differences disappear when we turn to the high end. From my own experience, I found the same saturation and distortion, and the same response curve differences between different vinyl with a platinum Rega Planar 3 (excellent audiophile turntable input range) with a cell Denon DL-110 (voice coil high output). For cons, the trend "serious before, acute withdrawal," which gives a "warm and round" is definitely not a feature of the "vinyl sound" is unique to my system read-only.
 
We can also ask whether the defects highlighted here are not offset by the qualities of vinyl, the digital copy could not reproduce. A blind test conducted with the material used to prepare the samples, same source, same ACD, showed that the loss of quality due to scanning are negligible, even if they are audible: http://www.hydrogenaudio (http://www.hydrogenaudio). org / forum [...] = 21 & t = 7953"
 
We have also seen that blind, without prejudice to the race and high volume nasty labels, a remastering of 1998, once compensated volume, seems extremely bad for all listeners, compared to the record original.
 
I hope you enjoyed this test, and allowed you to have a more concrete idea of ​​the faults in the sound of vinyl.



I'm most curious about the statement " blind test conducted with the material used to prepare the samples, same source, same ACD, showed that the loss of quality due to scanning are negligible, even if they are audible"  Not sure what this is supposed to mean.  If it means, there is a an audible loss of quality due to digitization of an LP -- or even a an audible difference --  that doesn't seem to be demonstrated in the link provided.

Btw, has anyone rigorously examined the per-play variability of a turntable system?  I've been told that this alone could make any ABX of vinyl vs a 'needledrop' problematic.  If there's an audible difference between the same LP played back twice, then the results of  a vinyl vs needledrop would be impossible to ascribe to one cause.
Title: Skeptoid: Digital vs Vinyl
Post by: mzil on 16 September, 2012, 04:02:38 PM
If there's an audible difference between the same LP played back twice, then the results of  a vinyl vs needledrop would be impossible to ascribe to one cause.

Not if that needledrop is literally the same playing of the vinyl, via the Meyer/Moran trick (http://www.aes.org/e-lib/browse.cfm?elib=14195) of digitizing and then converting back to analog, via a professional CD recorder with a very low latency A to D, and then right back to A, "loop," virtually instantaneously. [Level matched, obviously, and using a wired A/B/X switch box .] Which is why I advocated it in another thread. 

The advantages are many:

-same wow and flutter and overall speed error for both the vinyl and the needledrop version
-same needle wear/condition
-synchronized [Just make sure the CD recorder's latency is very low. It worked fine for their SACD vs CD test so I don't see why it would be an issue here.]
-same number and location of ticks and pops
-same "thump" noise when listeners ask to have a musical section replayed
-same master [This is critically important, yet people blissfully compare CDs to vinyl all the time and ignorantly assume they are from the same master, yet they pretty much never are.]
Title: Skeptoid: Digital vs Vinyl
Post by: Pio2001 on 16 September, 2012, 04:14:16 PM
For us non-Francophones, here's Google Translate's attempt of the Conclusion.  Some bits are less comprehensible than others ;>


Thanks, krabapple,
The translation is indeed terrible. Here is a corrected version :

Quote
We found that the difference between vinyl and CD can be heard on digital copies, which is not surprising, vinyl does not have perfect sound.
More surprisingly, the greatest differences are not always found between CD and vinyl (RMB, bad press), but also between a vinyl and another (Depeche Mode - A Question of Lust), and even throughout one side of a single vinyl (Legendary Pink Dots - Pennies for Heaven / Evolution).

Among other differences, the differences in bass / treble are important. They vary from one disk to another, from one label to another (the German distributor of Depeche Mode, Intercord, produces vinyl that always miss treble), but a trend is always present : these copies of vinyl have more bass (about 50-100 Hz), and less treble (around 3000 - 12000 Hz) than their counterparts in CD. This trend can not be attributed to the digitizing chain. This is a characteristic of the cartridge used to read the disc, a Stanton Trackmaster EL. Cartridges have various response curves, which determine a large part of their "tonal color."
Hence, the CD has the merit to linearize the frequency response curve, that is very unstable with vinyl.

We can ask ourselves if these differences disappear when we turn to the high end. From my own experience, I found the same saturation and distortion, and the same response curve differences between different records using a Rega Planar 3 turntable (excellent low-end audiophile turntable) with a Denon DL-110 cartridge (high output moving coil). On the other hand, the trend "more bass, less treble" which gives a "warm and round" sound is definitely not a feature of the "vinyl sound". This is a property of my own playback system.

We can also ask whether the defects highlighted here would not be balanced by other qualities of vinyl, that the digital copy could not reproduce. A blind test conducted with the system used to prepare the samples (same source, same A/D Converter), showed that the loss of quality due to digitalisation is negligible, if audible at all : http://www.hydrogenaudio.org/forums/index....f=21&t=7953 (http://www.hydrogenaudio.org/forums/index.php?act=ST&f=21&t=7953)

We have also seen that in a blind listening test, without preconceptions about the loudness race and the big nasty record companies, a remastering of 1998, once the levels are aligned, sounds extremely bad for all listeners, compared to the original version.

I hope you enjoyed this test, and that it allowed you to have a more precise idea of the inherent flaws in the vinyl sound.


I'm most curious about the statement " blind test conducted with the material used to prepare the samples, same source, same ACD, showed that the loss of quality due to scanning are negligible, even if they are audible"  Not sure what this is supposed to mean.  If it means, there is a an audible loss of quality due to digitization of an LP -- or even a an audible difference --  that doesn't seem to be demonstrated in the link provided.


Nope, the translation is wrong. It's not "even if they are audible", but "if audible at all" 
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 17 September, 2012, 11:40:21 AM
A disadvantage to any method involving LP is the latency of replay -- the time it takes to move the arm back to the start of a section.  But otherwise, I agree , mzil's  method is probably the best we can do.  (And as regards his last point, anyone who tests transparency of digital recording by comparing a commercial CD to an LP has no idea what they're doing.)
Title: Skeptoid: Digital vs Vinyl
Post by: krabapple on 17 September, 2012, 11:49:05 AM
We can ask ourselves if these differences disappear when we turn to the high end. From my own experience, I found the same saturation and distortion, and the same response curve differences between different records using a Rega Planar 3 turntable (excellent low-end audiophile turntable) with a Denon DL-110 cartridge (high output moving coil). On the other hand, the trend "more bass, less treble" which gives a "warm and round" sound is definitely not a feature of the "vinyl sound". This is a property of my own playback system.


So, if I understand clearly, you're saying the boosted bass and reduced treble that you observed from LP, compared to CD, was a product of *your* particular setup, and *not* the vinyl mastering vs CD mastering?  Even though you found the same response when you used a different TT and cartridge?  This seems contradictory to me.


Title: Skeptoid: Digital vs Vinyl
Post by: Pio2001 on 17 September, 2012, 05:23:01 PM
No, I mean that I observed the same distortion artifacts (e.g. the RMB EP has the same intermodulation in treble, the Question of Lust 7" has the same loss of clarity), and the same difference of frequency response from vinyl to vinyl (eg. the Intercord german pressings have less treble than the french of english pressings, the last track of Legendary pink dots has much less treble than the first), but the frequency response of the Denon cartridge is different from the Stanton's. It doesn't have the same lack of treble, for example.

Thus, while all my vinyl samples seem to have less treble than my CD samples, this is Stanton's fault. Denon disagrees with this. It is not, in any way, a demonstration that CD sounds metallic, cold and dry compared to vinyl.

But if all german records of Depeche Mode have less treble than the same records imported from England, this is not Stanton's fault. Denon agrees with this. There are variations from a record to another.

I didn't bother posting samples from different pressings of a given CD from the same master, as they are usually bit-wise identical.
I checked this with Dead Can Dance - Within the Realm of a Dying Sun, english CD vs french CD. Same result with Depeche Mode - Strangelove (maxi mix), taken from the 1987 cardboard sleeved english Maxi-CD vs the german 1991 reedition of all Depeche Mode maxi-CD. Bit for bit identical... until the fade out, that doesn't have the same length of both CDs.
Title: Skeptoid: Digital vs Vinyl
Post by: robbo1802 on 27 September, 2012, 03:03:06 AM
Hello Pio,

It has been a long time, I think I last corresponded with you in the EAC forums under the username Bobhere.

I happened upon this thread through a search for something else and saw your avatar. 

I for one was grateful for the appearance of CDs, up until that time I had spent a truly obscene amount of money on vinyl playback equipment (not that CD players were cheap, my Sony CDP101 cost about $1100AUD when released - if memory serves).

I will add a few more points as grist to the mill.  The difference between different vinyl pressings both within a label and between labels is a rather complicated mess.  Not only can these differences be attributed to which master/mother/stamper was used but also to how many mothers/stampers/records had been created from each higher level part of the process, worn out or damaged stampers were more common than people realized (not to mention disgusting considering the cost of records).  Also the quality of the vinyl was a big issue, the major companies used a lot of recycled vinyl, initially when they got back records for recycling they would use a big punch to remove the label area and throw it away but as vinyl costs increased they took to grinding the paper label off and reusing all the vinyl, this often lead to contamination of the subsequent pressings - I remember a high end Decca I bought that had a piece of paper embedded in the playing surface!  Yet this recycled vinyl was often of better quality that some new vinyl which had too much filler.

To make things worse, the analog tapes used to create the masters were often shipped to the country where the records were mastered and pressed.  This caused numerous problems such as the different playback tapedecks having different playback qualities - these could be much greater that you would think amounting to multiple dB variance in the top end and serious distortion issues.  Even worse there is no guarantee that the different tapes were even of the same generation, i.e whether they are 1st or 2nd generation copies of the stereo master.

I did a lot of work comparing different playback chains in the seventies and for me the phono cartridge was always the weak link.  I must add that I live in a sub-tropical climate and this has serious effects on both the performance and longevity of phono cartridges, especially moving coils (due to the type of suspension normally used on MCCs of that period).

I used to test cartridges against each other using 2 identical but modified Pioneer PL1000A linear tracking turntables, they each had modified  tonearms, phono wiring, and each had its own identical RIAA preamp (and MCC head amp) with variable input impedance.  The two direct drive turntable motors could be slaved to the one master clock so that they rotated at identical speed.  Despite this (and a variable spead control with allowed the two records to be brought into close synch)  direct switching AB testing was never very successful, the slight out of synch was too confusing.  In the end testing consisted of running the two turntables about 20 seconds apart and comparing the same sound fragments one after the other.

All this required multiple copies of the same records and at one time I had 5 copies of each of Sheffield records, Harry James, Amanda McBroome, and Dave Gruisin as testers - I did say obscene amounts of money, didn't I?.  There were of course many other test record sets of 5 as well as some 2 and 3 record sets of the Nimbus Supercuts.  I will add that the Sheffield Labs CDs sound quite poor compared to my (fallible) memory of the LPs, but of course we are comparing direct cut LPs to CDs mastered from hissy analog tape recordings (using valve electronics (if memory serves).

Enough rambling.

Regards,
Bob