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CD-R and Audio Hardware => Vinyl => Topic started by: 2Bdecided on 2013-10-04 14:48:16

Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: 2Bdecided on 2013-10-04 14:48:16
Anyone who still clings to waveforms and DR numbers to "prove" that a particular vinyl release has a greater dynamic range (i.e. less compression) than the CD version must watch this video...

http://www.youtube.com/watch?v=n-AE9dL5FG8 (http://www.youtube.com/watch?v=n-AE9dL5FG8)


Found courtesy of this thread...
http://forums.stevehoffman.tv/threads/is-t...r-vinyl.330706/ (http://forums.stevehoffman.tv/threads/is-the-dr-database-really-accurate-for-vinyl.330706/)


Some of the YouTube comments are what you'd expect on YouTube (=clueless!), and some of the Steve Hoffman forum comments are what you'd expect from vinyl fans. However, the video itself is very clear, and it makes a change to hear someone in the industry talk absolute sense in public.

We have had similar threads on HA where we've dissected this stuff, but this video has a very clear fact in it that we've been unable establish with 100% certainty before. I won't say what it is in this first post because that would spoil it.

Cheers,
David.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 15:48:51
Thanks for this.

Those who took exception to any previous comments (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=98199&view=findpost&p=822333) I made on the subject can suck it note that I was correct.

BTW, the link should point to post #95.  Crapple's Safari on IOS seems to linking to the next post.  I haven't tried other browsers. Firefox correctly points to my post.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 16:05:56
Seriously, suck it (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=99723&view=findpost&p=825917)!

...and by suck it, I mean buy me a beer.

EDIT: just to pile on (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=101602&view=findpost&p=844553).
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: bilbo on 2013-10-04 16:20:43
Seriously, suck it (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=99723&view=findpost&p=825917)!


But how do you really feel
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 16:21:55
Vindicated!
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: krabapple on 2013-10-04 16:36:16
Bravo!
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: cliveb on 2013-10-04 16:42:17
His results are certainly interesting, but I question his conclusions.

He knows for sure that the vinyl was cut from the same digital master as the CD, so he concludes that it cannot possibly have more DR. But the TT meter unambiguously shows that the vinyl has a higher peak-to-avg ratio. So in an objective sense, the DR of the vinyl *is* greater. But of course whatever that increased DR is on the vinyl, it certainly is *not* genuine signal that is missing from the CD.

Something in the process of cutting and/or playing the vinyl is artificially expanding the DR. My uninformed guess would be mechanical overshoot of an insufficiently damped cutting head. (I can't see how the playback stylus could possibly overshoot - it can't move beyond the confines of the groove).

And finally, he states the vinyl cannot possibly sound better than the CD. But in my book, it's entirely plausible that this artificially expanded DR may sound more pleasing. Or less pleasing, of course. The vinyl's extra DR is some kind of distortion, for sure, but it could be euphonic.

The question to ask is whether this characteristic is typical. Do *all* vinyl cuts tend to expand the DR of the master they are made from, or is it peculiar to this particular example?

In summary, this youtube posting proves nothing - it merely adds a further complication. The plot thickens.

EDIT: sorry - it *does* prove one thing: that if the DR values for CD and vinyl releases are different, it does not necessarily show that they were cut from different masters.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 16:50:57
overshoot

Nah, try running a square wave through a high-pass or all-pass filter.

is it peculiar to this particular example?

Based on the preponderance of the evidence I have seen? No!

if the DR values for CD and vinyl releases are different, it does not necessarily show that they were cut from different masters.

...and that differences in waveforms do not necessarily show that they were cut from different masters.

AFAIC, this is all that matters.

Slam dunk!
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: edwardar on 2013-10-04 17:14:20
Slightly off topic, but possibly linked.  I noticed this recently:

I took a mildly clipped CD (Brian Wilson - Live at the Roxy), ripped to wav and halved the volume in Audacity.  I then compressed this file as a LAME MP3.  The MP3 had a DR of 1 or 2 higher than the source, though I could not hear a difference when compared with the original at matched volume.

[My unfounded speculation is that it's possible the DR meter takes into account very brief peaks in amplitude which contain minimal audible information ("energy"?).]

Edit: oh, and the MP3 waveform 'looked' more dynamic.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 17:16:50
Not off-topic at all and yes, I think that's absolutely correct.  You could have also decoded to 32-bit float PCM an mp3 created from the original source without reducing the level.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2013-10-04 17:28:38
Since I posted that thread (one of two that was linked to earlier) I think I also learned quite a bit about the TT DR Meter. I even learned in that thread from 2Bdecided that some excessive phase-nudging can dramatically change the measurement.

I noticed that Ian Shepherd (a person I've come to respect) mentioned in that video that it was a "blunt instrument." Beyond my initial impressions I think I've always viewed it as such. The problem is is that it's the best (though imprecise) instrument I"m aware of. Obviously I can't tell anyone here that I hear or perceive more dynamic range or something because, within this forum, that is rightfully irrelevant and considered subjective.

I've understood (rightly or wrongly) that phase-nudging, EQing, etc can have a moderate effect on that DR score. I'm not totally convinced that more than 3 or 4 decibels is just chalked up to some cartridge or whatever. I could be wrong.

The only way we can be certain that a vinyl master is different is if the record company gives us such info. When I've requested it in the past some always do (and don't always give me the answer I want to hear either) but many others don't even respond to such emails.

...but then again: some brief reply from a record company saying something to the effect of "we understand that the engineer submitted a separate master for the vinyl. Thanks for your interest in our products!" could very well mean "yeah, the engineer EQed the same brickwalled recording slightly differently for the vinyl." Really all we have is subjective observations when comparing to vastly different mediums like CD and LP. (And yes: CD will obviously always win in precision against an archaic but still loved format like vinyl records.)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: cliveb on 2013-10-04 17:29:11
overshoot

Nah, try running a square wave through a high-pass or all-pass filter.

It seems that you have interpreted my use of the term "overshoot" as suggesting that the cutting head might "interpolate" a clipped wavetop. That is not what I was suggesting at all.

What I am wondering is when there is a (non-clipped) peak with a fast rise-time in the signal, it's possible that the cutting head might fail to stop its lateral excursion at the correct point, and continue on for a while (due to a combination of inertia and insufficient damping). This would result in bigger peaks, and hence a greater peak-to-avg ratio. But I must stress that this is pure speculation on my part.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 17:31:37
I wouldn't be surprised if the math involved in characterizing the mechanical mechanism and the the filter response turned out to be the same.

With that said, strike the "Nah" in my reply.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: krabapple on 2013-10-04 17:53:31
His results are certainly interesting, but I question his conclusions.

He knows for sure that the vinyl was cut from the same digital master as the CD, so he concludes that it cannot possibly have more DR. But the TT meter unambiguously shows that the vinyl has a higher peak-to-avg ratio. So in an objective sense, the DR of the vinyl *is* greater. But of course whatever that increased DR is on the vinyl, it certainly is *not* genuine signal that is missing from the CD.


Right, and that's what he's saying.

Quote
And finally, he states the vinyl cannot possibly sound better than the CD. But in my book, it's entirely plausible that this artificially expanded DR may sound more pleasing. Or less pleasing, of course. The vinyl's extra DR is some kind of distortion, for sure, but it could be euphonic.


I'm pretty sure he agrees , either in the video or the comments below it.  He certainly says , circa 12:25, that if you like the sound of vinyl,  you may well prefer the sound of the vinyl version of this track, regardless of how its DR was generated.



Quote
In summary, this youtube posting proves nothing - it merely adds a further complication. The plot thickens.

EDIT: sorry - it *does* prove one thing: that if the DR values for CD and vinyl releases are different, it does not necessarily show that they were cut from different masters.



Exactly.  And if it's the case that the masters were the same, then....the 'extra' DR is entirely due to either artifactual or intentional post-processes, not a natively higher DR of the source.  This is logically obvious, but  I think having 'proved' it this way is a pretty significant thing!
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: 2Bdecided on 2013-10-04 18:06:19
Once you square-wave / clip something, it's really hard to do anything to it without raising the measured peak-to-average level.

Anyone remember this noise clip?
http://web.archive.org/web/20050209010438/...3.net/norm.html (http://web.archive.org/web/20050209010438/http://ff123.net/norm.html)
(about 1/4 down the page)

Many modern CDs are just pathological examples of this. A low pass filter, a high pass filter, proper sub-sample interpolation, and an all pass filter - all these things will raise the peak-to-average ratio compared with calculating it for the raw samples. Yet the sound doesn't change at all - it's subjectively the same signal. TT DR is measuring numbers, not sounds.


I think the easiest way to compare like-for-like with an "objective" "DR" tool is to run the CD version through an all-pass filter first and use that as the baseline against which you compare the vinyl version. Or just assume, if the CD looks clipped, that there's 3-4dB more energy in the clipped peaks just waiting to burst out the moment you fiddle with them.

Cheers,
David.

P.S. Glad you like this greynol. Many of us suspected this, and pointed to identical clipping on CD and LP to suggest the same master was used, but it's nice to get it confirmed by a mastering engineer: "exact same master, 4dB higher DR measurement on vinyl, no actual improvement".
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-04 18:13:19
http://www.hydrogenaudio.org/forums/index....showtopic=66401 (http://www.hydrogenaudio.org/forums/index.php?showtopic=66401)
http://www.hydrogenaudio.org/forums/index....showtopic=68641 (http://www.hydrogenaudio.org/forums/index.php?showtopic=68641)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2013-10-05 06:43:32
In general and for the sake of constructive argument I have a few earnest/non-rhetorical questions:

Did anyone really not understand before that a 3-to-4 dB difference with the TT meter could be attributed to vinyl playback itself? (That was somewhat rhetorical but seriously: discuss if possible.)

How do you think this would play out if a non-dynamic master was used on both the CD and the LP? (e.g. all of my needle drops that have really bricked masters have very similar looking waveforms and are usually within ~1 dB with that meter.)  Ian Shepherd is known to engineer decent recordings in a time when most do not. His example was a pretty dynamic CD mix.

Semi-related: I was reading elsewhere where Mr. Shepherd said that Nine Inch Nails' newest album "Hesitation Marks" on vinyl sounded subjectively better than either the CD or (controversially) so-called "audiophile" release. I think I can submit examples of each and we can look at that one example and observe differences the TT meter "detects/"

Thoughts?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: krabapple on 2013-10-07 01:14:34
Rather interesting experiment done by Ian Shepherd, identifying a likely cause of the DR discrepancy:

http://forums.stevehoffman.tv/threads/is-t...11#post-9481216 (http://forums.stevehoffman.tv/threads/is-the-dr-database-really-accurate-for-vinyl.330706/page-11#post-9481216)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: krabapple on 2013-10-07 01:18:07
How do you think this would play out if a non-dynamic master was used on both the CD and the LP? (e.g. all of my needle drops that have really bricked masters have very similar looking waveforms and are usually within ~1 dB with that meter.)  Ian Shepherd is known to engineer decent recordings in a time when most do not. His example was a pretty dynamic CD mix.



But that's the funny thing.  To many audiophiles of the sort that populate the Hoffman board,  the CD waveform on Ian's video would be considered 'brickwalled'  and 'non-dynamic'.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2013-10-07 01:29:24
Now this is getting pretty interesting. Thanks for the link!

I, for one, appreciate Ian's determination to get to the bottom of all of this. Does anyone think there will ever be a decent way to measure the dynamic range of a record?

I was hesitant to ascribe more than a 3-4 dB increase in vinyl measurement to the other reasons (or combinations thereof) mentioned. Yesterday I found a needledrop of mine that actually "measured" a full 5 dB greater than the CD. I'm certain they're the same master. Not only does it sound like it (the record actually sounds a little worse) but the waveform from the vinyl looks almost exactly the same as that of the CD. No real or artificial peaks.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: markanini on 2013-10-07 11:15:23
Rather interesting experiment done by Ian Shepherd, identifying a likely cause of the DR discrepancy:

http://forums.stevehoffman.tv/threads/is-t...11#post-9481216 (http://forums.stevehoffman.tv/threads/is-the-dr-database-really-accurate-for-vinyl.330706/page-11#post-9481216)

So Ian was able to repoduce the higher DR measurement by narrowing stereo width of the master in his DAW. 
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2013-10-07 20:48:56
Someone in the Hoffman thread just brought up a fair question IMO and I'll paraphrase it in the following paragraphs:

Why do all (by all I'm speaking from my personal experience thus far as well) the eighties LPs measure almost exactly the same as their CD counterparts? Both are equally dynamic but for some reason always have pretty much the same DR "value" as one another.

...these records should, in theory, be "scoring" 3-4 dB higher on that meter as well. The records have the same issues of crosstalk, soundstage, etc. that we're taking Ian's word is changing the the "value" of his own recording.

(None of my musings here should be construed as me once again taking the position that the DR meter is reliable for vinyl rips.)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2013-10-07 21:09:23
Why does anyone use the TT DR Meter? Where is the algorithm specified? Why isn't it based on BS-1770?

It seems like it is pretty much completely useless.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-07 21:27:08
I couldn't agree more.

In addition to that, and while this may be extraneous to your point:
ABXing vinyl from its digital master is generally assumed.  When armed with the knowledge of "DR" figures, differences generally get attributed to perception of differences in dynamic range.  When those specific differences don't exist, but the obvious unrelated tells do, expectation bias can (and often does) prevail.  This is especially true when the imagined difference supports the point being argued.

Back to the original topic, does anyone want to add to the wiki article on vinyl myths?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: DVDdoug on 2013-10-07 23:12:32
Quote
Why do all (by all I'm speaking from my personal experience thus far as well) the eighties LPs measure almost exactly the same as their CD counterparts? Both are equally dynamic but for some reason always have pretty much the same DR "value" as one another.

...these records should, in theory, be "scoring" 3-4 dB higher on that meter as well. The records have the same issues of crosstalk, soundstage, etc. that we're taking Ian's word is changing the the "value" of his own recording.
I believe it's the lack of excessive compression (or lack of excessive compression).    If you take an "pure" uncompressed recording of an orchestra and run it through an all-pass filter, the DR "measurement" or crest factor should be unaffected,  because all of the frequency-components sum-up randomly either way.   

But a compressed/limited file has been limited wherever the frequency-components "randomly" sum-up to exceed the threshold/limit.    When you all-pass, the timing of the various frequency components is "randomized" again... 
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2013-10-08 01:37:14
Quote
Why do all (by all I'm speaking from my personal experience thus far as well) the eighties LPs measure almost exactly the same as their CD counterparts? Both are equally dynamic but for some reason always have pretty much the same DR "value" as one another.

...these records should, in theory, be "scoring" 3-4 dB higher on that meter as well. The records have the same issues of crosstalk, soundstage, etc. that we're taking Ian's word is changing the the "value" of his own recording.
I believe it's the lack of excessive compression (or lack of excessive compression).    If you take an "pure" uncompressed recording of an orchestra and run it through an all-pass filter, the DR "measurement" or crest factor should be unaffected,  because all of the frequency-components sum-up randomly either way.   

But a compressed/limited file has been limited wherever the frequency-components "randomly" sum-up to exceed the threshold/limit.    When you all-pass, the timing of the various frequency components is "randomized" again...


That seems like a reasonable explanation.

Thanks also for your willingness to discuss this.  I'm actually interested in this particular topic without some a priori expectations or agenda to gloat about. I just want to know the truth about it all and nothing more or less.

That's why I tend to trust Ian Shepherd's findings and (lack of) motives for looking into this. He comes across as one who likes both digital and vinyl for different reasons and doesn't seem to have some axe to grind.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: krabapple on 2013-10-08 03:34:35
Why does anyone use the TT DR Meter? Where is the algorithm specified? Why isn't it based on BS-1770?


there was a link in that thread at one point to a brief white paper describing the TT Meter's workings....not code though, if that;s what you mean.

Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: extrabigmehdi on 2013-10-08 20:01:06
You can download the music samples related to the video to do you own experiments in the following link.
They were "volume matched" using R128 in wavelab , so you can abx them directly if you wish:
http://forums.stevehoffman.tv/threads/is-t...14#post-9485602 (http://forums.stevehoffman.tv/threads/is-the-dr-database-really-accurate-for-vinyl.330706/page-14#post-9485602)

My thought regarding the TT meter : ok , a big DR value isn't a warranty that the record has a good dynamic range.
However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.
So the TT meter is still doing it's job to some extent.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: DVDdoug on 2013-10-08 22:45:07
Quote
My thought regarding the TT meter : ok , a big DR value isn't a warranty that the record has a good dynamic range.
However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.
So the TT meter is still doing it's job to some extent.

I'm pretty sure the TT meter is calculating something that correlates with perceived dynamic range to some extent... 

But, we know there is some uncertainty in the calculation...  Maybe we should allow for  up to 4dB "error" or uncertainty.    i.e., If two recordings measure within 4dB, there may be no real difference. 

If someone wants to kill some time, I'll propose a casual experiment:
- Listen to a batch of recordings (at least 10) and give each recording a "dynamics" score.  It would probably be best to use a 0-10 or 0-100 scale rather than trying to use dB.    But if you have a lot of experience with the TT meter, it would be OK to predict the TT meter result. 

Use recordings that you have not measured with the TT meter.    And, it would probably be best if all of the sample recordings are either vinyl or digital.       

- Check with the TT meter to see what kind of correlation you get. 

Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-08 23:02:10
up to 4dB "error" or uncertainty.

How many data points were used to derive this number?

Why is this metric even being given any credence in the first place?

I like your proposal, especially the part about listening before measuring.  Suffice it to say, in the spirit of the experiment, listening before looking at waveforms should also be a requirement.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: pisymbol on 2013-10-09 05:07:57
Why does anyone use the TT DR Meter? Where is the algorithm specified? Why isn't it based on BS-1770?


there was a link in that thread at one point to a brief white paper describing the TT Meter's workings....not code though, if that;s what you mean.


I can upload it somewhere later but essentially (without formulas):

Measuring DR

Each channel of the audio signal is splitted into blknum blocks of 3 seconds length. The RMS
is calculated for each block as the square root of the double sum over all input samples
squared, divided by the block size in samples. The Peak is calculated as the maximum of the
absolute value from the block.

Each RMS and Peak value is entered into a histogram with 10,000 discrete values ranging
from -100 dB to 0 dB in steps of 0.01 dB.

The DR value for each channel j can then be derived as the difference between the second
largest Peak value and the RMS-sum over the upper 20% histogram values converted to dB.

The overall DR is finally calculated as the average of the channel DR values rounded to the
next integer value.

Using the RMS-sum in (4) results in the overall RMS of the upper 20% of the input material,
eliminating the contribution of small Peaks. This method also ensures that the resulting DR
value is virtually independent from the block size used (3s in this example) as long as this is
small compared to the overall input material length.

Limiting the DR-measurement to the upper 20% of the blocks with maximum RMS is a
compromise that allows to somewhat compare a wide variety of different material in a
quantitative way. Also in highly dynamic Material only the loudest parts, which usually best
reflect the processing of the material (compression etc.), contribute to the DR measurement.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: pisymbol on 2013-10-09 05:28:38
My thought regarding the TT meter : ok , a big DR value isn't a warranty that the record has a good dynamic range.
However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.
So the TT meter is still doing it's job to some extent.


What I want to know is this...

If I have a CD at DR5/6 and a vinyl rip at DR11/12, can they really be the same master? And even more importantly, what exactly is throwing off the algorithm I posted above?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: mjb2006 on 2013-10-09 09:20:36
If I have a CD at DR5/6 and a vinyl rip at DR11/12, can they really be the same master?


Ian Shepherd's video is talking about a specific situation:

The same peak-limited master as was used for prepping the CD/digital releases was also given to the vinyl mastering house, where it was then subjected to an unknown amount of additional processing that's required for putting audio onto playable vinyl.

At the very least, presumably, the bass was made more mono, and bandpass filtering was applied to roll off frequencies outside of the 30 Hz to ~20 KHz range (maybe not even that high). Either of these things alone can increase the measured DR value, effectively acting as an expander, reintroducing a few dB of "peakiness" to the audio. So whether you consider the vinyl master to be the "same" depends on whether you're taking this into consideration.

And that's only talking about what audio goes onto the wax. When you rip it, you're introducing many more variables and slight changes to the audio via your particular playback and recording system, which can nudge the rip's peak-to-RMS ratio in one direction or the other. All together, a ~6 dB difference in the measured DR value probably isn't out of the question.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: pisymbol on 2013-10-09 13:08:08
If I have a CD at DR5/6 and a vinyl rip at DR11/12, can they really be the same master?


Ian Shepherd's video is talking about a specific situation:

The same peak-limited master as was used for prepping the CD/digital releases was also given to the vinyl mastering house, where it was then subjected to an unknown amount of additional processing that's required for putting audio onto playable vinyl.

At the very least, presumably, the bass was made more mono, and bandpass filtering was applied to roll off frequencies outside of the 30 Hz to ~20 KHz range (maybe not even that high). Either of these things alone can increase the measured DR value, effectively acting as an expander, reintroducing a few dB of "peakiness" to the audio. So whether you consider the vinyl master to be the "same" depends on whether you're taking this into consideration.

And that's only talking about what audio goes onto the wax. When you rip it, you're introducing many more variables and slight changes to the audio via your particular playback and recording system, which can nudge the rip's peak-to-RMS ratio in one direction or the other. All together, a ~6 dB difference in the measured DR value probably isn't out of the question.


It sure seems a lot to me given the algorithm. Most needle drops I've seen are around the same TT score (+-1dB).

I'm trying to understand WHAT is causing spurious peak variations to offset the DR?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: 2Bdecided on 2013-10-09 13:24:55
I'm trying to understand WHAT is causing spurious peak variations to offset the DR?
An all-pass filter makes the peak value of a clipressed digital master jump up by about 3dB, and doesn't change the RMS at all - hence the measured DR value "improves" by about 3dB.

A phono cartridge and complimentary RIAA filtering are (at best!) an all pass filter (plus some attenuation of the frequency extremes, plus complete blocking of DC, plus hopeless response at very high frequencies, plus distortion, plus noise etc etc ...).


The biggest problem with the DR meter isn't that it gets vinyl so "wrong" - it's that it measures a certain kind of numerical (and, in the waveform: visible) property without any regard for how audible and/or inappropriate to the content it is. Even that isn't really a "fault" with the meter - it's a fault with the way people sometimes unthinkingly use the results.

Put an all pass filter in the algorithm, and you'll solve the vinyl vs CD problem. However, this will then downplay the "badness" of clipression and clipping (despite the fact is can be audibly objectionable), while still penalising "normal" compression (which reduces the dynamic range without introducing clipping) as much as now.

I don't like to criticise because I can't think of a better way of doing it. In what it is (a numerical measurement of peak to average ratio), it's working fine. The problem is, it's not a reliable measure of unwanted distortion (which is what most people object to), it's only a half-decent measure of clipping if there's no post-processing, and it can have no concept of what a particular recording "should" sound like in terms of dynamic range.

Cheers,
David.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: pisymbol on 2013-10-09 13:38:42
I'm trying to understand WHAT is causing spurious peak variations to offset the DR?
An all-pass filter makes the peak value of a clipressed digital master jump up by about 3dB, and doesn't change the RMS at all - hence the measured DR value "improves" by about 3dB.

A phono cartridge and complimentary RIAA filtering are (at best!) an all pass filter (plus some attenuation of the frequency extremes, plus complete blocking of DC, plus hopeless response at very high frequencies, plus distortion, plus noise etc etc ...).

Cheers,
David.


But 6dB difference David? Is that typical?

My assumption has been that a 6+ dB difference is MOST LIKELY caused by an altogether different master, not RIAA correction or a particular cart's FR...etc.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: markanini on 2013-10-09 15:04:55
Why is this metric even being given any credence in the first place?


Probably cause it's the first tool of it's kind in a time when loudness wars and dynamic range became a hot button issues to audiophiles.

I did some comparisons between TT DR results and BS1770 loudness range (using Hofa 4U Meter) on a few titles that I had in both CDDA and needle drop versions. First I noticed the BS1770 numbers didn't tell me that analogue recordings from the '70s had tons of dynamic range when I could subjectively tell there's moderate compression on both(probably from the master tape). Second on titles that sounded similar the numbers were identical or the vinyl reported one value smaller dynamic range, closer to what's expected. Just a small test but if it's enough to draw any conclusions it seems the BS1770 is more accurate.

With this in mind and since people will keep using these tools could there be any merit to implementing a BS 1770 loudness range version of foo_dynamic_range (http://www.hydrogenaudio.org/forums/index.php?showtopic=88373)?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: ianshepherd on 2013-10-09 22:02:14
With this in mind and since people will keep using these tools could there be any merit to implementing a BS 1770 loudness range version of foo_dynamic_range (http://www.hydrogenaudio.org/forums/index.php?showtopic=88373)?

The equivalent value in R128 terms is the "peak to loudness ratio", or PLR.

We're experimenting with displaying it in my Perception plugin - it gives values that are similar to, but different from , the DR values.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-10 17:48:50
up to 4dB "error" or uncertainty.

For giggles I took the CD version of the file found here (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=98201&view=findpost&p=816283) and ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.

The DR value jumped from 5 to 10.

EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: skamp on 2013-10-10 18:32:10
ran it through Audition's subsonic rumble filter


What does it do?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-10 18:40:42
It's simply a steep high-pass filter intended to remove subsonic rumble.  I couldn't find an all-pass filter in Audition so I chose one that wasn't going to alter the audible frequency response.

Hopefully google can answer any additional tangential questions.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-11 01:23:12
However I think the reverse is true, a too low value (let's say below 6) indicate that the dynamics has been too much squashed.

I wouldn't be so sure about this either:
http://www.hydrogenaudio.org/forums/index....howtopic=102963 (http://www.hydrogenaudio.org/forums/index.php?showtopic=102963)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2013-10-11 04:46:31
up to 4dB "error" or uncertainty.

For giggles I took the CD version of the file found here (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=98201&view=findpost&p=816283) and ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.

The DR value jumped from 5 to 10.

EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.


That seems fair and appropriate considering the source. That Ortofon OM5e was a terrible cartridge with an obvious treble-bias at the expense of midrange. I've since happily replaced it, along with the Debut III, with a Denon DL-110 on a slightly modded Technics SL 1200.

...not that I'll likely be contributing any new samples to that thread as I'm going to just admit that I was most likely hearing things on many of those examples. They really do sound different to me but probably not usually for the reasons I thought they did.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2013-10-11 05:41:02
It should be no great revelation to anyone. This stuff has been discussed in our community for years now.
http://www.hydrogenaudio.org/forums/index....showtopic=80679 (http://www.hydrogenaudio.org/forums/index.php?showtopic=80679)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: user1 on 2014-04-03 07:18:38
up to 4dB "error" or uncertainty.

For giggles I took the CD version of the file found here (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=98201&view=findpost&p=816283) and ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.

The DR value jumped from 5 to 10.

EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.
A subsonic (rumble) filter may be built in, as an option (like RIAA filter tweaks), into the cutting-lathe console. It would be useful if a cutting engineer can comment on this.

(http://www.gearslutz.com/board/attachments/mastering-forum/140156d1255654585-aes-sterling-tour-show-marino-main-console.jpg)

Also note what one vinyl mastering/engineering service states in their Q&A (http://www.dongrossinger.com/qa.shtml):

Quote
[blockquote]Q: These days, many independent productions are completed at home in project studios. What can mastering offer to enhance the final sound of these projects?   

A: Often home productions are recorded and mixed under less than perfect acoustical conditions. I can make educated decisions and offer options to the producer that will translate well to the real world. My experience allows me to make major or subtle changes, while working in conjunction with the artist, producer or label, which really can improve the final sound of any project.[/blockquote]

Refs:
http://ekadek.com/?page_id=14 (http://ekadek.com/?page_id=14)
http://www.gearslutz.com/board/4684881-post21.html (http://www.gearslutz.com/board/4684881-post21.html)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: user1 on 2014-04-03 10:44:20
Another thing I forgot to mention was this peculiar note from a 2009 technical article in Stereophile (http://www.stereophile.com/content/cut-and-thrust-riaa-lp-equalization-page-2):
Quote
....Neumann's name became attached to the correction because its lathes—on which a great many of the world's vinyl records have been cut down the decades—have been reported to incorporate an additional record EQ time constant of 3.18µs (50.05kHz). As we will see, this isn't correct....

Via little oversights like this .... negligent, ignorant or otherwise unaware mastering/cutting engineers may be creating records with "unwanted"/distorted content.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: extrabigmehdi on 2014-04-03 12:03:55
I'm wondering if multiplying "%replaygain_track_gain%" and  "%replaygain_track_peak%" datas ,
doesn't provide a more reliable information about the dynamic range, than with  the TT Dynamic Range meter .
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Juha on 2014-04-26 15:51:57
...

...

ran it through Audition's subsonic rumble filter with 6dB of attenuation to prevent clipping.  The DR value jumped from 5 to 10.  EDIT: I bumped the treble a little bit in an attempt to more closely match the vinyl version and the DR value increased to 11.


You don't necesarily need to do anything else but trim the level -3dB down to get the DR value for CD rip rise from DR8 to DR11.

Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: TomasPin on 2014-04-26 20:07:46
I'm wondering if multiplying "%replaygain_track_gain%" and  "%replaygain_track_peak%" datas ,
doesn't provide a more reliable information about the dynamic range, than with  the TT Dynamic Range meter .

I've been interested in a sort of "ReplayGain Database" for a while now... It would be better than the DR meter for vinyl rips, right?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: markanini on 2014-04-26 21:19:15
I'm wondering if multiplying "%replaygain_track_gain%" and  "%replaygain_track_peak%" datas ,
doesn't provide a more reliable information about the dynamic range, than with  the TT Dynamic Range meter .

I've been interested in a sort of "ReplayGain Database" for a while now... It would be better than the DR meter for vinyl rips, right?

That would in fact not be much different from the PRL (Peak to loudness ratio) you see in some recent metering software for DAWs. The PLR has shown less of a tendency to inflate vinyl scores in my tests: http://www.hydrogenaudio.org/forums/index....st&p=862623 (http://www.hydrogenaudio.org/forums/index.php?showtopic=105173&view=findpost&p=862623)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: krabapple on 2014-12-17 16:44:59
quickie question -- does foo_dynamic_range 1.1.1  use the same loudness metric as TT DR Meter?

IOW , is it more 'reliable' as in an indicator of sound quality?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: DVDdoug on 2014-12-17 20:59:43
Quote
IOW , is it more 'reliable' as in an indicator of sound quality?
I don't know if it's a better indicator or dynamic range, someone else can answer that...

I would NOT say dynamic range (or dynamic contrast) is necessarily a measure of "quality".  It's one characteristic of the sound.  You can't say higher dynamic range is always better. 

One of the most common effects used in audio production is dynamic compression (reduction of dynamic range) and that's not done to make the quality worse!    Sometimes it's overdone in my opinion, and the opinion of many others, but it's done because that's what sells.       

On the other hand, dynamic expansion is almost never used in audio production (except in the special case of a noisegate).    And most popular music is not performed dynamically...  Classical music tends to be very dynamic and it's generally recorded with little compression, somtimes no compression.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-01-19 07:20:44
With all due respect, the argument is illogical. What is missing is consideration of the DR of the original master file. The author of the YouTube post has missed the possibility that the vinyl cutting process may have faithfully preserved more of the DR of the master than the CD burning process did.

The superior DR demonstrated in the vinyl may not be distortion, it may be that the CD DR is lower than the master. He doesn't demonstrate this at all.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Vietwoojagig on 2015-01-19 09:28:24
With all due respect, the argument is illogical. What is missing is consideration of the DR of the original master file. The author of the YouTube post has missed the possibility that the vinyl cutting process may have faithfully preserved more of the DR of the master than the CD burning process did.

The superior DR demonstrated in the vinyl may not be distortion, it may be that the CD DR is lower than the master. He doesn't demonstrate this at all.
He was clearly comparing the dynamics of the vinyl against the original digital source, from which the vinyl was made of and not against a CD rip. So the TT meter sais, that the vinyl copy has more dynamics than the original digital source, which should not be possible. That is the statement. Nothing more.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-19 16:43:59
What is missing is consideration of the DR of the original master file.

This consideration was directly addressed at 4:50 into the video:

https://www.youtube.com/watch?feature=playe...AE9dL5FG8#t=291 (https://www.youtube.com/watch?feature=player_detailpage&v=n-AE9dL5FG8#t=291)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-01-19 17:57:03
With all due respect, the argument is illogical. What is missing is consideration of the DR of the original master file. The author of the YouTube post has missed the possibility that the vinyl cutting process may have faithfully preserved more of the DR of the master than the CD burning process did.

The superior DR demonstrated in the vinyl may not be distortion, it may be that the CD DR is lower than the master. He doesn't demonstrate this at all.

That is illogical in itself.

How would the CD lower such dynamic ranges? Only vinyl, the format itself, the mechanic playback system, the creation process of vinyls can introduce such levels of distortion.

This should be clear even if you compare a dirt cheap CD player to a high end vinyl system.
Vinyl cannot directly store any digital signal. The added distortion by this required pre-processing alone... Add to that the rumble, speed inaccuracies, wow, flutter, the distortions added by the tonearm, low output level requires a pre that further changes the sound (add additional noise, distortion, crosstalk, frequency response deviations) ...
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: mzil on 2015-01-19 18:25:17
We've been using electronic level meters now for many decades however the old style, mechanical meters used predominantly before the 80's, as well as modern day LP record cutting lathe heads (and TT styli?) have a property in common referred to as "ballistics". This refers to the tendency of the physically moving structure (tracing or representing the analog input waveform as best it can) to both be sluggish to fast and sudden alterations as well as a tendency to overshoot the peak values it is instructed to, especially on quick, transient peaks in the music (easily seen from percussion instruments), mostly because of its physical inertia due to its mass, which of course an electronic meter lacks. Meter ballistics can be desirable at times and they can be emulated or "dialed in" to modern day electronic meters, however they can't be "dialed out" of physical meters.

LP records should actually be expected to have transient peaks in the recording which exceed the input signals' true values, hence "added dynamic range" (albeit artificial) due to this inertial mass induced overshooting of the cutter head's needle, when the recording is physically etched onto the blank surface. I guess this issue would go away if we were to convert to laser cutting lathes to go along with our laser record players [which have actually existed] but for the time being the added hashiness seen [less "flat topping" I believe they call it] and the artificially greater dynamic range values seen in these simplistic measuring algorithms is a true manifestation of the actual (distorted) wave form etched and played back from the vinyl, due to cutting head ballistics.

It is an artifact and a distortion to the true signal, although it is quite possible some (many?) people actually "prefer" it. [If it is even audible. I'm not claiming it is; I don't know.] Me? I'd rather have an indistinguishably different, exact replication of the studio master, levels intact, so I'm sticking to digital.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-01-19 19:33:58
With all due respect, the argument is illogical. What is missing is consideration of the DR of the original master file. The author of the YouTube post has missed the possibility that the vinyl cutting process may have faithfully preserved more of the DR of the master than the CD burning process did.

The superior DR demonstrated in the vinyl may not be distortion, it may be that the CD DR is lower than the master. He doesn't demonstrate this at all.

That is illogical in itself.

How would the CD lower such dynamic ranges? Only vinyl, the format itself, the mechanic playback system, the creation process of vinyls can introduce such levels of distortion.

This should be clear even if you compare a dirt cheap CD player to a high end vinyl system.
Vinyl cannot directly store any digital signal. The added distortion by this required pre-processing alone... Add to that the rumble, speed inaccuracies, wow, flutter, the distortions added by the tonearm, low output level requires a pre that further changes the sound (add additional noise, distortion, crosstalk, frequency response deviations) ...


The process of determining discrepancy must be scientific, not based on dogma and assumption. We need to see the DR of the master. The CD creation process is algorithmic and digital,mans assumptions about its purity may be misguided.

Talk of the "pure signal" and the assumption that the CD press is a viable proxy may be erroneous,
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-01-19 19:40:46
What is missing is consideration of the DR of the original master file.

This consideration was directly addressed at 4:50 into the video:

https://www.youtube.com/watch?feature=playe...AE9dL5FG8#t=291 (https://www.youtube.com/watch?feature=player_detailpage&v=n-AE9dL5FG8#t=291)


No it's not. He says it was produced from the swm master file, and he says "the wave form looked liked this..." But there is no proof St is the case. Why not? Let's see it. I'm not saying it's not true, just that it isn't proven here,
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-19 19:40:47
The DR value of the master used to create the vinyl in the video was 8, or are you accusing Ian Shepherd of lying?

"This vinyl master was made from the same digital file that was used to create this CD master"
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-01-19 21:23:21
The process of determining discrepancy must be scientific, not based on dogma and assumption.  We need to see the DR of the master.

You can verify everything I said by doing measurements. Nothing I said is dogma and assumption, but what you say and imply definitely is:
- assumption that CD changed the dynamic range
- assumption that vinyl preserves dynamic range more faithfully
- assumption that superior DR (which is a wrong assumption in itself, the TT DR meter simply yields higher numbers) in the vinyl is not due to distortion
- assumption that Ian is lying?
..

These technical assumptions of yours are demonstrably wrong.

I guess you have a vinyl rig at home. Have you never even done a measurement as simple as platter speed? If you had, you'd see the gross imperfections of vinyl systems.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-01-19 22:47:28
The process of determining discrepancy must be scientific, not based on dogma and assumption.  We need to see the DR of the master.

You can verify everything I said by doing measurements. Nothing I said is dogma and assumption, but what you say and imply definitely is:
- assumption that CD changed the dynamic range
- assumption that vinyl preserves dynamic range more faithfully
- assumption that superior DR (which is a wrong assumption in itself, the TT DR meter simply yields higher numbers) in the vinyl is not due to distortion
- assumption that Ian is lying?
..

These technical assumptions of yours are demonstrably wrong.

I guess you have a vinyl rig at home. Have you never even done a measurement as simple as platter speed? If you had, you'd see the gross imperfections of vinyl systems.


No, I didn't say these things were definitely true. I said they couldn't be ruled out as possibilities without access to, or visibility on the DR of the original master.  They may be demonstrably wrong, I accept that, but I'm asking that they be actually demonstrated to be wrong in this case.  This is just scientific process.

In fact, I'm not even asking for it, just suggesting it would be more rigorous proof to do so.

Personally,minding care. I'm know what I like to hear, and don't obsess on derived numbers to prove it. Trust your ears is the best advice in the clip in my humble opinion. sorry to cause offence to anyone, was entirely unintentional!
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-01-19 22:58:19
The DR value of the master used to create the vinyl in the video was 8, or are you accusing Ian Shepherd of lying?

"This vinyl master was made from the same digital file that was used to create this CD master"


Not accusing anyone if anything. He didn't say that at all. He said that the same digital file was used to master both the cd burn and vinyl press. He didn't specify the observed DR in that master file, although he may have implied it when he said the waveform "looked like the cd" image I admit. 

Now we all know that the CD waveform is futsed with,  it's possible, just possible that the two have different DR. That's all, small point, nobody get frantic,
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-01-19 23:10:27
Sorry, but I'm not going to demonstrate how digital audio and vinyl works for you here.

We do know that vinyl has many imperfections. And we know that the TT DR meter has a bad algorithm. Heck, even inaudible phase shifts can significantly alter TT DR readings..
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2015-01-19 23:33:22
Sorry, but I'm not going to demonstrate how digital audio and vinyl works for you here.

We do know that vinyl has many imperfections. And we know that the TT DR meter has a bad algorithm. Heck, even inaudible phase shifts can significantly alter TT DR readings..


Of those imperfections that you previously stated, what effect does the wow & flutter of any competently-engineered turntable have to do with artificially "boosting" the DR? (As a sidenote I really think the wow & flutter thing is grossly exaggerated. Of course it's not the precision of digital but I've never owned a TT that exhibited perceptible wow & flutter...unlike tape decks.)

I'm asking in earnest and I apologize if there's something I'm missing.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-01-20 00:06:27
I didn't say anything about audibility.
Regarding DR, well, both wow and flutter will change the waveform. Wow will change the number of samples analyzed in a fixed window. Flutter will add intermodulation.

With a good turntable neither should make a significant difference, but the TT meter seems to use a very naive algorithm (please someone send me a link to an implementation) that is susceptible to all kinds of "distortions" that really shouldn't make any difference in dynamic range.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Engelsstaub on 2015-01-20 00:13:03
I didn't say anything about audibility.
Regarding DR, well, both wow and flutter will change the waveform. Wow will change the number of samples analyzed in a fixed window. Flutter will add intermodulation.

With a good turntable neither should make a significant difference, but the TT meter seems to use a very naive algorithm (please someone send me a link to an implementation) that is susceptible to all kinds of "distortions" that really shouldn't make any difference in dynamic range.


Ah, ok. I understand now. Thanks
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Wombat on 2015-01-20 00:59:20
I am not very familar with yinyl gear and how bad it really works but again i think it helps to link to Archimago's blog:
Roksan TMS (1) Wow & Flutter - PlatterSpeed test (http://archimago.blogspot.de/2014/11/measurements-roksan-tms-1-wow-flutter.html)
When this is what Wow&Flutter does it is no wonder all waveforms look completely different when vinylized.
If this is something different, sorry. I have no clue in this direction.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-20 05:08:51
Now we all know that the CD waveform is futsed with

We suspect the CD master was derived from a higher-resolution master which would have entailed a reduction in bit-depth and sample rate.  This would not have altered the DR value.

To suggest there was some other mechanism that reduced the value of the DR measurement of the CD is to say that Ian Shepherd is either incompetent (supposing the mechanism was unintentionally put into play) or dishonest (supposing the mechanism was intentionally put into play).
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-20 05:31:54
If this is something different, sorry. I have no clue in this direction.

As far as the video is concerned, the exact mechanism that results in an increase in DR value doesn't matter. The takeaway here is that DR figures can't be used reliably to determine whether vinyl and CD were sourced from different masters.

FWIW, I don't believe wow and flutter have much, if anything, to do with the DR figures.  I'm pretty sure xnor was just throwing them out as examples of the many forms of distortion inherent in vinyl transcription and playback.

I think mzil's explanation cuts closest to what is going on.  In the past I've characterized it as a predominantly underdamped highpass response, which has similar characteristics when viewed from a control systems point of view.  At least this is what I recall from a previous life.  Consider whether a stylus can provide a DC response.  Then consider whether it can provide a square wave and what the output will look like instead.  Then have a gander at some of the zoomed waveforms in the other threads on this subject, some of which certainly predate this topic.

This one was particularly entertaining (for me at least):
http://www.hydrogenaud.io/forums/index.php...st&p=875605 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=104328&view=findpost&p=875605)
http://www.hydrogenaud.io/forums/index.php...st&p=875637 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=104328&view=findpost&p=875637)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-20 06:40:15
the TT meter seems to use a very naive algorithm (please someone send me a link to an implementation)

http://www.hydrogenaud.io/forums/index.php...st&p=617223 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=68945&view=findpost&p=617223)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Porcus on 2015-01-20 11:42:38
Regarding algorithm, one should IMHO consider (I do not make a claim it will work in the end, only that it should help against certain unwanted issues and is worth a try) a "robust statistics" approach. Those methods using median rather than mean in order to not let extremes influence too much.

For "mean" one could for example use median volume rather than RMS. Or calculate RMS over each short window and then take the median of these RMS windows; that has a chance to eliminate bursts from single clicks/pops in the vinyl. But I guess that the mean loudness isn't the critical part (so heck, why not use ReplayGain or EBU-R128?).

Then for the dynamic range, the worst to use would be file peak - it is prone to a single error.  But for example median excess over mean, dropping those which are lower than mean, because those may be prone to surface noise?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-01-20 12:09:38
Of course the large frequency response (including phase!) deviations from flat is what will by far have the largest influence on the TT DR numbers.

@greynol: thanks for the link, that's what I found too
So given that even just changing the volume of a track changes the TT DR readings ... why would anyone still use that anyway?

Just take an EBU-R128 loudness meter?
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-20 15:13:24
Median over mean won't fix the vinyl DR inflation problem, as it is not caused by a few large peaks; rather, all the horizontal envelopes on the master resulting from heavy compression/"brickwall" limiting become angled after being subjected to vinyl.  In addition, gain must be reduced in order to prevent this new shape from clipping.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: castleofargh on 2015-01-20 15:14:00
With all due respect, the argument is illogical. What is missing is consideration of the DR of the original master file. The author of the YouTube post has missed the possibility that the vinyl cutting process may have faithfully preserved more of the DR of the master than the CD burning process did.

The superior DR demonstrated in the vinyl may not be distortion, it may be that the CD DR is lower than the master. He doesn't demonstrate this at all.

That is illogical in itself.

How would the CD lower such dynamic ranges? Only vinyl, the format itself, the mechanic playback system, the creation process of vinyls can introduce such levels of distortion.

This should be clear even if you compare a dirt cheap CD player to a high end vinyl system.
Vinyl cannot directly store any digital signal. The added distortion by this required pre-processing alone... Add to that the rumble, speed inaccuracies, wow, flutter, the distortions added by the tonearm, low output level requires a pre that further changes the sound (add additional noise, distortion, crosstalk, frequency response deviations) ...


The process of determining discrepancy must be scientific, not based on dogma and assumption. We need to see the DR of the master. The CD creation process is algorithmic and digital,mans assumptions about its purity may be misguided.

Talk of the "pure signal" and the assumption that the CD press is a viable proxy may be erroneous,


so when comparing a format full of heavy fidelity weaknesses, and a digital conversion, your incentive is to blame the digital file. funny to see you talking about assumption^_^.

it's really not hard for you to demonstrate your strange theory. take a high res file, and convert it to CD resolution with whatever resampler and dither you like. then see how much the operation changed the values of the DR meter. and good luck getting something like 4db less on the 16bit file. even with all the already mentioned reliability problems from that DR meter I doubt you'll get there.

to play the devil's advocate, I could imagine a messed up situation where some ultrasounds would be louder than the audible range(scary!!!!), so cutting them out when converting to CD could maybe affect the DR. in that silly hypothesis the "loss of dynamic" would be in fact saving our ears.
now imagine what ultrasounds of high amplitude(higher than the audible range in my example) would do when playing the vinyl  . the needle would go all "I believe I can fly, I believe I can touch the sky!"
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-20 15:23:02
I don't believe DR inflation is caused by high frequencies. All the tweaking I have done in an attempt to emulate the phenomenon has been focused on altering the phase characteristics and/or frequency response at the subsonic end.

Tweaking the high-end was only window dressing by comparison:
http://www.hydrogenaud.io/forums/index.php...st&p=846950 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=102895&view=findpost&p=846950)
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Wombat on 2015-01-20 19:14:39
This one was particularly entertaining (for me at least):
http://www.hydrogenaud.io/forums/index.php...st&p=875605 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=104328&view=findpost&p=875605)
http://www.hydrogenaud.io/forums/index.php...st&p=875637 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=104328&view=findpost&p=875637)

Thanks! I remember lightly reading some of these things. Really very interesting how the phase change confuse the DR meter.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: castleofargh on 2015-01-21 07:44:02
I don't believe DR inflation is caused by high frequencies. All the tweaking I have done in an attempt to emulate the phenomenon has been focused on altering the phase characteristics and/or frequency response at the subsonic end.

Tweaking the high-end was only window dressing by comparison:
http://www.hydrogenaud.io/forums/index.php...st&p=846950 (http://www.hydrogenaud.io/forums/index.php?s=&showtopic=102895&view=findpost&p=846950)


oh I also don't believe it's the reason, but that's the only actual possibility I could come up with for real possible change in DR that could come from the CD conversion itself(to go along with greyghost uber open minded theory that CD could be guilty). I was saying that it wouldn't amount to much in real life music, and thus that CD conversion had most certainly nothing to do with the problem at hand.

my personal hypothesis would push toward the amplitude accuracy of vinyls(or the lack of it). but I'm really a noob when it comes to vinyls.

PS:I heard the one saying I was a noob whatever the subject! it's true but not nice.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-01-21 20:08:42
Now we all know that the CD waveform is futsed with

We suspect the CD master was derived from a higher-resolution master which would have entailed a reduction in bit-depth and sample rate.  This would not have altered the DR value.

To suggest there was some other mechanism that reduced the value of the DR measurement of the CD is to say that Ian Shepherd is either incompetent (supposing the mechanism was unintentionally put into play) or dishonest (supposing the mechanism was intentionally put into play).


No it is not. It's merely pointing out that scientific process has not been followed rigorously in evidencing the proof. There is an assumption gap. Its not a personal attack.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-01-21 20:34:56
I think xnor already alluded to the actual assumption gap which is at play here. 

I would hope this is about knowing the truth rather than just criticizing a presentation made by an industry professional in his free time in order to help people.  While it appears he hasn't proven it to your satisfaction, Ian Shepherd is still right.  Shooting down his video for not being tedious enough won't change the landscape.  You'll also have to have a go at the all the other evidence compiled on the subject if that is what you wish to do.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-01-21 21:40:31
No it is not. It's merely pointing out that scientific process has not been followed rigorously in evidencing the proof. There is an assumption gap. Its not a personal attack.

So I suggest you take a couple of 96/24 tracks, convert them to 44.1/16 and check with the dreaded TT DR meter yourself, like I (and possibly others) did before. You may find .1 or .2 lower or even higher "dynamic range", but the DR rating should be identical.

Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Thegreyghost on 2015-05-17 00:26:05
With all due respect, the argument is illogical. What is missing is consideration of the DR of the original master file. The author of the YouTube post has missed the possibility that the vinyl cutting process may have faithfully preserved more of the DR of the master than the CD burning process did.

The superior DR demonstrated in the vinyl may not be distortion, it may be that the CD DR is lower than the master. He doesn't demonstrate this at all.

That is illogical in itself.

How would the CD lower such dynamic ranges? Only vinyl, the format itself, the mechanic playback system, the creation process of vinyls can introduce such levels of distortion.

This should be clear even if you compare a dirt cheap CD player to a high end vinyl system.
Vinyl cannot directly store any digital signal. The added distortion by this required pre-processing alone... Add to that the rumble, speed inaccuracies, wow, flutter, the distortions added by the tonearm, low output level requires a pre that further changes the sound (add additional noise, distortion, crosstalk, frequency response deviations) ...


The process of determining discrepancy must be scientific, not based on dogma and assumption. We need to see the DR of the master. The CD creation process is algorithmic and digital,mans assumptions about its purity may be misguided.

Talk of the "pure signal" and the assumption that the CD press is a viable proxy may be erroneous,


so when comparing a format full of heavy fidelity weaknesses, and a digital conversion, your incentive is to blame the digital file. funny to see you talking about assumption^_^.

it's really not hard for you to demonstrate your strange theory. take a high res file, and convert it to CD resolution with whatever resampler and dither you like. then see how much the operation changed the values of the DR meter. and good luck getting something like 4db less on the 16bit file. even with all the already mentioned reliability problems from that DR meter I doubt you'll get there.

to play the devil's advocate, I could imagine a messed up situation where some ultrasounds would be louder than the audible range(scary!!!!), so cutting them out when converting to CD could maybe affect the DR. in that silly hypothesis the "loss of dynamic" would be in fact saving our ears.
now imagine what ultrasounds of high amplitude(higher than the audible range in my example) would do when playing the vinyl  . the needle would go all "I believe I can fly, I believe I can touch the sky!"


I'm not blaming anything or biased in eithe direction. Merely pointing out the obvious flaw in the scientific process presented.

Although the vitriol I'm getting for pointing it out is certainly pointing to biases in other's opinions.

If it's so unquestionable then let's see the simple proof in the original master DR.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2015-05-17 00:43:31
Ask/tell Ian.  Comment on his video, if you like.

Coming back after several months to try to argue this same line isn't going to change anything.  You found your loophole and are clinging to it. Good for you!   

In the meantime, for the rest of us who have discussed this on multiple occasions, Ian's video only supplied further evidence for what we already knew, or at the very least strongly suspected.  I know I've put links up to these other discussions on more than one occasion.

To put it another way, Ian just missing the bullseye on a technicality is small potatoes. We aren't in desperate need of a slam dunk on the subject.
Title: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: xnor on 2015-05-17 10:46:56
Thegreyghost, what is the problem?
Even if the record contained a perfect copy of the digital files (which it doesn't, it contains a distorted version), the playback system has so many flaws that the resulting DR meter rating will be off, because it's a bad algorithm.

Just look at the output of a turntable of a single tone. The frequency will be off, there will be phase shift vs other frequencies, the frequency will constantly change by up to a couple Hz, there will be lots of nonlinear distortion and noise, ...
Repeat the same with pulses and you will also see resonances of the moving masses involved, high levels of crosstalk especially at low frequencies (the stereo image will usually change quite a bit due to that limitation) ...
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Isabelxxx on 2016-03-29 21:03:16
"TT Dynamic Range meter "lies" about vinyl's dynamic range"

The title of the topic should be changed since it does not reflect the actual content of the thread and it's misleading.

The meter can no lie in any way about a measurement done to the input files, whether it comes from vinyl, sourced from digital or the radio. It would be like saying Total RMS or peak analysis does not work the same for ALL digital input, which is plainly wrong since the meter does not make any assumption about the source of the input.

Another entire thing is how you interpret the results and the conclusions you got from that.

The ripped vinyl to digital DOES have different peak to RMS values than the "original" master; therefore due to different processes the vinyl cut & pressing requires and the subsequent recording needed to go back to digital, the final output is different. Another entire thing is discussing if that makes sense at all or you get any real improvement over the original brickwalled master. That's the subjective part, psycho-acoustics.

BUT the DR meter has nothing to do with that. Audition/Izotope/.... let me calculate Total RMS values, ITU BS.1770-2 loudness, etc. the fact some of those measures are good in some situations but not appropriate in others has nothing to do with them lying in any way while measuring. Are you joking or what? It only reproduces a well known fact, choose your measurement tools according to what you want to measure.

Or are we going to say a thermometer lies about the temperature of a swimming pool just because the person who wants to measure it does not consider the swimming pool may have in fact different layers of water at different temperatures?

I'm surprised to see how a forum who is so anal about scientific things makes such claims -supported by the mods- only as a personal "vendetta" against self-claimed "audiophiles" who believe in magic instead of listening and measuring samples.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-29 22:49:10
https://en.wikipedia.org/wiki/Scare_quotes

...oh, I see you used them in your post as well. ;)
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Isabelxxx on 2016-03-30 00:03:37
The entire content on the thread, not only the title, is full of crap and nonsense as already explained in my post.

I would not have spent my time to talk about the tittle ignoring how you played with words. Read my post, answer to it if you wanna but don't reply me with an evasive answer.

Again, what surprises me is how some of you, and specifically you (a moderator), used the tread for your vendetta.

Making use of TOS 1 (so essentially now this is THE TRUTH here) and violating TOS 8 since Dynamic Range of the source in this context CAN NOT be objectively measured as ironically the thread has demonstrated and falls into the subjective perception.

Where are the tests to support the claims?
Or are we judging the tool?  (back to my post, you can not claim with quotes or without them a tool meter lies about nothing)

In fact the tool measures properly the dynamic range of the vinyl recording; what is not measuring right is the DR of the source used to make that vinyl pressing. (i.e. the rip of the vinyl is not equal to the source due to filtering and other processes) So the title continues to be misleading.

Back to dynamic range, one could say that digital clipped source sounds less dynamic than the vinyl rip* from the same source and tha wouldt be perfectly fine since "dynamic range" in this context (in which TT DR tool is used) means perceived compression.  But again, there are no such tests in this thread so...

*(declipped as it's proven due to various intermediate processes pointed by you and others here or in other topics)

You essentially have taken a truth and applied it for your own convenience, even if that means to use it out of context, apply wrong terms or make unscientific claims.
Ironic, as I say, in this forum with its reputation. Obviously you know you are plainly wrong and can not edit one year later the entire thread to mask your real intentions behind this topic.

Then you are the first to point others about their ego and how to support claims but this is a good reference for anyone to see how all that becomes nothing when you have personal interest. Therefore let me ask it again and add something more: the title should be edited and the content rectified with a later post clarifying what's true and what not.

hey... TT DR tool in fact provides wrong "Dynamic range measurements" for CD too if you know how to "tweak" the input.
Does that mean the CD or the tool is crap? Or a re-evaluation of what Dynamic Range means or how it's measured is needed?

A thread clean of crap and people using this "final evidence" for their own personal vendetta, with a clear title as "TT DR tool is NOT the appropriate tool to measure dynamic range among different mediums" or "TT DR tool is NOT the appropriate tool to measure dynamic range of the source". Or even ""TT DR tool is NOT the appropriate tool to measure dynamic range"
would fit better in this forum which such strict TOS which clearly were not applied here since the mods were more interested in their interest than the rules they put there years ago.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 00:06:26
Sounds like you're the guy with a vendetta.

The title wasn't created by me and I have no intention of changing it.  Maybe another staff member might find your bloviated posts more compelling.

Did you even watch the video?

Do you understand that there isn't one person who is saying the program is literally lying (as in presenting a numerical value different than the one it calculated)?  This especially includes the author of the topic who has time and again demonstrated a firm grasp on the subject matter, thank you very much.

It's a provocative title intended to draw a reader in.  And your bumping it will only serve to catch more eyes, even better that you're introducing even more controversy by claiming the content of the discussion is nonsense.  This means that even more rationally-minded people will see that using DR values to compare CD against vinyl is a bad idea.

Thank you for that! :D
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Isabelxxx on 2016-03-30 01:04:35
For sure. I watched the video and read the SH thread posted first. Wait... Did I mention the video? Did I say the video is wrong or something? Could make corrections to the video too but I did not enter there... but the thread posted HERE, its title and its content. And then in the 2nd post I further explained some questionable behavior, like yours.

Also I read this one pointed somewhere in the thread.
http://forums.stevehoffman.tv/threads/is-the-dr-database-really-accurate-for-vinyl.330706/page-11#post-9481216

The page 12 is gold, essentially someone pointing Ian Shepherd that TT DR meter does NOT measure the "Dynamic Range" of the source used for the vinyl, true; but it could well measure the perceived compression or "Dynamic range" of the recording from the vinyl. Ian's answer: "shut up, even if your new discussion makes sense (based in my own arguments) this my moment of glory."
i.e. people here and at that thread worked hard to show others how vinyl cutting, pressing and playback affects the final output which makes DR metering comparisons between vinyl and digital useless. Agree.
So now... the same argument is used to point that the "non faithful" to the source vinyl rip in fact sounds more dynamic than the source so it could be the TT meter in fact is measuring perfectly fine the dynamic range. At least what we perceive as that.
Obviously it fails to measure the DR of the source, it's crazy! You are not measuring that! Who really thought that?! And the thread is all about this; the vendetta against those audiophiles that said some vinyl pressings used different masters than the CDs using as evidence DR differences.
But proving wrong those people has nothing to do with the rest of the discussion...

And no. This is not a pro-vinyl argument but an explanation of what's going on. The same can be applied to the digital source and it will produce higher DR measurements. I just point to the vinyl related claims because those were used wrong and only show half of the truth.
The tool is not vinyl-flawed or medium-flawed, the real reasons are others. And those mechanism behind the DR measurements affect dynamic range perception, whether they are applied in the analog or the digital domain.

So... as I noted a re-evaluation of what is "dynamic range" is needed since the tool was never meant to measure real dynamic range used but dynamic range perception; obviously -no test needed- one could say the CDs would score higher dynamic range having less SNR when using the same source for both!

And yes, the thread is full of crap. There is even 3 or 4 posts by you right from the star saying.... what... nothing?

Essentially like now but at least with more words. Still open to receive an answer. Post 81.
https://hydrogenaud.io/index.php/topic,102895.msg919344.html#msg919344

Btw I never said the content of the discussion is nonsense but it is full of nonsense. It's not the same.

My fridge is full of cokes. It doesn't mean there are only cokes there, I like water too. Funny seeing how you like to play with words you missed that...
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 01:15:26
Well of course I don't believe you feel that all the posts in the thread aren't crap.  I mean, you contributed to it, right?
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 01:16:56
Anyway, allow me to repeat my "crap" because it doesn't in any way support what was presented in the video:
https://hydrogenaud.io/index.php/topic,99723.msg825917.html#msg825917
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 01:19:05
More of my "crap" because it doesn't in any way support what was presented in the video:
https://hydrogenaud.io/index.php/topic,102963.0.html
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 01:19:23
More of my "crap" because it doesn't in any way support what was presented in the video:
https://hydrogenaud.io/index.php/topic,66401.0.html
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 01:37:44
So... as I noted a re-evaluation of what is "dynamic range" is needed since the tool was never meant to measure real dynamic range used but dynamic range perception;
What it was meant to do and what it is actually capable of doing may be two very very different things.

Perhaps someone knows of some evidence that objectively demonstrates that TTDR reliably measures the perception of dynamic range.

If you didn't know anything about this community one of the first things you should know is that it rejects the idea that perception cannot be tested on the grounds that it is subjective.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 02:07:23
Here's a link to help first time readers avoid this silly distraction of nitpicking:
https://hydrogenaud.io/index.php/topic,102895
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: eric.w on 2016-03-30 04:33:34
I guess this has been covered already, but here's an example of (heavy) EQ'ing causing a DR5 sample to increase to DR14  (the song is "Copy Of A", from NIN's Hesitation Marks, audiophile mastered edition, measured with DR-Meter 1.4a).

This is an extreme example just for fun. Of course, it sounds really tinny after boosting the treble 16dB.

sox -G 02\ Copy\ Of\ A.wav copyofa.wav rate 44100 trim 5:00
sox -G copyofa.wav copyofa_eq.wav treble 16

Quote
-----------------------------------------------
 Statistics for:    copyofa.wav
 Number of Samples: 997658
-----------------------------------------------

                  left              right

 Peak value:     -0.10 dB   ---    -0.00 dB
 Avg RMS:        -5.88 dB   ---    -5.30 dB
 DR channel:      5.04 dB   ---     4.62 dB
-----------------------------------------------

 Official DR value:  DR5
===============================================
Quote
-----------------------------------------------
 Statistics for:    copyofa_eq.wav
 Number of Samples: 997658
-----------------------------------------------

                  left              right

 Peak value:     -0.00 dB   ---    -0.50 dB
 Avg RMS:       -15.49 dB   ---   -14.78 dB
 DR channel:     14.29 dB   ---    13.55 dB
-----------------------------------------------

 Official DR value:  DR14
===============================================
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Juha on 2016-03-30 06:18:32
I guess this has been covered already, but here's an example of (heavy) EQ'ing causing a DR5 sample to increase to DR14 

Isn't that behaviour kind of natural compared to just changing the level 3dB down, as I mentioned earlier (page 2)?
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: pelmazo on 2016-03-30 09:14:35
The title of the topic should be changed since it does not reflect the actual content of the thread and it's misleading.
This is a hilarious suggestion. Whoever thinks that the moderators' job is to dynamically change the thread titles to reflect the discussion in the thread must be new to internet fora.

If this wasn't meant as a joke: I'm opposing it, but I'm confident the moderators wouldn't be inclined to do this, anyway.

The page 12 is gold, essentially someone pointing Ian Shepherd that TT DR meter does NOT measure the "Dynamic Range" of the source used for the vinyl, true; but it could well measure the perceived compression or "Dynamic range" of the recording from the vinyl. Ian's answer: "shut up, even if your new discussion makes sense (based in my own arguments) this my moment of glory."
No, that is not what Ian answers. It is your malevolent distortion.

You are obviously referring to SergioRZ's speculations. The problem with him seems to be that he's not even wrong (https://en.wikipedia.org/wiki/Not_even_wrong). He is clueless enough to take the coincidence that the DR meter sometimes agrees with his perception of dynamic range, as a sign that it may be purposefully programmed that way. That's a very basic logical fallacy, and the discussion with him could stop there.

It is quite clear that the tool does not measure the perceived dynamic range, but rather a technical definition of dynamic range that is derived from the difference between average and peak power. If there is any confusion at all, it is between those different meanings of the same term.

If you are interested in the technical DR measure, the tool may well be the right one for you, and in this sense it probably doesn't lie at all. If you are expecting a measurement result from it that matches perceived DR, the tool will disappoint you. That's what Ian has shown, and that's what the discussion was about, modulo the nonsense that inevitably creeps in when people contribute who haven't a clue what they are talking about.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Isabelxxx on 2016-03-30 12:04:29
I had already read all those topics, anyway thanks for them greynol.

Other users could see, independently of my last post which added some things some of you may not agree with, how greynol is clearly not answering to anything I put. Just giving links and writing evasive answers.

Just saying.... I can be wrong or right about a part of the topic and still that has nothing to do about the other part.

Eric.W that manipulation does in fact affect dynamic range perception, another entire thing if that's enjoyable since the rest of the band is compressed. Again the tool measures Peaks to RMS, and your manipulation changes peaks to RMS so....
We can discuss the conclusion you make from the results but you can not discuss the results! And that's where this thread has failed. Check my first post. Not that I'm saying I disagree with most things from this thread ;)

Quote
This is a hilarious suggestion. Whoever thinks that the moderators' job is to dynamically change the thread titles to reflect the discussion in the thread must be new to internet fora.

Erm.... like greynol did at some point later in the thread? ;)

I love the arbitrary use of the TOS in this forum.

And again, if this thread is about the Tool NO ONE can make a claim about it lying or reporting wrong results. That's false and misleading.

If this thread is about the results and how they are interpreted, then the title needs a fix and there is a ton of misleading info within this thread and the links. Like any controversial topic, ok. But it doesn't hurt to rectify it. Or only the vinyl myths wiki can be edited?

Please don't be shortsighted. Even if 75% of this forum or this thread is true, and greynol is most times right that doesn't mean the forum or Greynol's word equates The Truth. At some point in your fight against people making claims without evidences you have fall in your own trap using anything as a gun against them and making other unscientific claims.

Quote
If you didn't know anything about this community one of the first things you should know is that it rejects the idea that perception cannot be tested on the grounds that it is subjective.
... read my 1st post. Either you are talking about the Tool and the measurements or about the dynamic Range and how it is perceived. The 1st requires a title fix and thread rectification, the second requires tests which I don't see here.

So it's you who should decide the topic (or the one who created it), not me. I simply pointed to both possibilities.

1st post in thread:
Quote
Anyone who still clings to waveforms and DR numbers to "prove" that a particular vinyl release has a greater dynamic range (i.e. less compression) than the CD version must watch this video...
For sure the thread was not limited to what the starting post seemed to suggest. That claim is true 100%, but the rest...
At the point you abandon discussing how the same master was used for the CD and the vinyl and start discussing how it sounds or what dynamic range means or how it's measured this topic lost their sense.
And don't tell me this thread has no post about that, or are you going to delete them too?

Quote
You are obviously referring to SergioRZ's speculations. The problem with him seems to be that he's not even wrong. He is clueless enough to take the coincidence that the DR meter sometimes agrees with his perception of dynamic range, as a sign that it may be purposefully programmed that way. That's a very basic logical fallacy, and the discussion with him could stop there.
.... so this thread is all about how the tool DOES NOT measure Dynamic Range. Now you say it does it right (?). Great.

Either it measures dynamics range and you have to accept filters and playback affects the dynamic range of a signal or what you are measuring is another thing. But you can not maintain both claims according to what you want to prove just to say to some of the audiophiles: f**ck you!
They deserve. ok.. but that's not the right way of proving nothing.

That discussion is perfectly fine and made sense and it's needed. So why Ian did not continue with it? I'm not saying he had all the evidences to make a new theory, but he simply found a flaw in the conclusions people have been making when using the TT DR tool and did not want to consider new options when people pointed to them. To me that's enjoying your moment of glory. No more. Ego.

Saying is "quite clear" what it measures or not to me is not so clear since it seems every time one really wants to test it people is more interested in personal attacks (masked within scientific claims) to other people beliefs than anything.

Again the "real" definition of Dynamic Range needs not clarification. A CD has less SNR. If the same master is used in vinyl and CD, the CD wins. End. If this thread is here is because there is more to what we understand as Dynamic Range. There is perception and we are trying to measure it. Don't say now you don't want to discuss it.

Declipping a signal does affect dynamic Range measurements. Most filters under right circumstances work like declipping tools (don't ask me examples, use any editor by yourself!). That magically transforms the source? No. But the output has different Dynamic Range since you modified the signal, saying the opposite is crazy. (therefore the vinyl recording can be more dynamic than the CD and the master, BUT the extra dynamics are not coming from the source, ok) Peak to RMS changes in both cases.
Does it sound more dynamic?
Well... that's what I suggest you to discuss if you really want to discuss about dynamic range. And that requires testing.

Pressings CD masters to vinyl is crazy anyway. Give me the real thing.

Do you see now how the tittle is wrong? TT Tool does not lie. The Peak to RMS in vinyl is higher than in CD when using the same source. Similar filtering can be applied to digital source to get the same results. And that in fact is what we are calling Dynamic Range and really changes! So... what part of the tittle is right?

I even agree with the most part written here but that's not the point. Anyway, someone with common sense could read between lines in my posts and get the idea. That's enough for me, so I'm done.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: j7n on 2016-03-30 12:35:15
Quote
Declipping a signal does affect dynamic Range measurements. Most filters under right circumstances work like declipping tools
While filters change the shape of the waveform, they don't necessarily remove any of the crackle and harshness that comes with clipping, so describing an equalizer a declipper is highly misleading.

I played around with the Phase Rotator in Reaper on a highly clipped track (Spice Girls - "Holler"). With the phase rotated by 90°, the peak level increased by whopping 9 dB (DR 5 -> DR 14) while the sound stayed exactly the same to my ear.

I suspect that some CDs with pre-emphasis in the DR database might have elevated ratings, due to high frequency peaks. My anecdotal experience indicates about 2 dB difference.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: pelmazo on 2016-03-30 13:23:54
And again, if this thread is about the Tool NO ONE can make a claim about it lying or reporting wrong results. That's false and misleading.
...
Even if 75% of this forum or this thread is true, and greynol is most times right that doesn't mean the forum or Greynol's word equates The Truth.
Aww, c'mon! Nobody has claimed that the thread title or greynol represents "The Truth". If you make a ridiculous exaggeration, it is your own fault. Most fair-minded people know very well how the thread title is meant to be understood. There's no TOS paragraph that would prevent formulating a provocative thread title.

Quote
.... so this thread is all about how the tool DOES NOT measure Dynamic Range. Now you say it does it right (?). Great.
Huh?

Which meaning of the term "dynamic range" are you presuming now?

The entire problem revolves around the discrepancies arising from mixing up various different meanings of this term. Once you or anybody else start to distinguish them properly and clearly, the problem goes away.

Quote
Either it measures dynamics range and you have to accept filters and playback affects the dynamic range of a signal or what you are measuring is another thing. But you can not maintain both claims according to what you want to prove just to say to some of the audiophiles: f**ck you!
They deserve. ok.. but that's not the right way of proving nothing.
Stop your rambling and start to think! There is absolutely no contradiction in what I wrote once you acknowledge that the tool doesn't measure perceived dynamic range, but measures something that has a technical definition, which does not directly relate to perception. If people interpret the measurement result such that they infer a certain perception, they are mistaken. That's what Ian argues quite correctly. If the tool itself would suggest or foster this misinterpretation, it could conceivably be called "lying", even if the measured result is technically correct.

This is quite similar to a thermometer not giving you a measure of the perceived temperature, since temperature perception varies with a number of other factors. If the thermometer purported to tell you the perceived temperature, it would be lying.

Not hard to grasp, is it?

Quote
Again the "real" definition of Dynamic Range needs not clarification. A CD has less SNR. If the same master is used in vinyl and CD, the CD wins. End. If this thread is here is because there is more to what we understand as Dynamic Range. There is perception and we are trying to measure it. Don't say now you don't want to discuss it.
There's no one "real" definition of dynamic range. There are several meanings to it, depending on the context. Measuring the dynamic range of a production has nothing to do with the dynamic range the recording medium offers. Same word, different meanings. The perceived dynamic range is yet another meaning, and a fuzzy one to boot. It would take psychoacoustic tests to determine it, and it isn't even clear if it would make much sense to do it, since human perception is not constant and uniform.

The TT tool does not measure perception, and if it is trying, it doesn't do a very good job, which is again the point Ian is making. Maybe it would make sense to discuss how it could be improved, but for the moment it seems to me to be a problem with the expectation rather than the implementation.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2016-03-30 13:57:36
What is this business about CDs and SNR?

I also want a link to the post in this discussion where I said my job is to dynamically change the thread title to reflect the discussion in the thread.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: Atmasphere on 2017-08-04 23:33:15
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What I am wondering is when there is a (non-clipped) peak with a fast rise-time in the signal, it's possible that the cutting head might fail to stop its lateral excursion at the correct point, and continue on for a while (due to a combination of inertia and insufficient damping). This would result in bigger peaks, and hence a greater peak-to-avg ratio. But I must stress that this is pure speculation on my part.

I know this is from the first page. I just saw this thread, which is quite interesting and thanks for putting it up.

A typical cutter head has a fair amount of feedback on it and so is damped. But there can be other factors such as distortion in the power amps for the cutter; my thinking is the 2nd harmonic is playing a role. LP systems make harmonic distortions, digital systems don't (they make aliasing). Between record and playback, I can see the most predominant of the distortion harmonics as adding some energy to the signal.

IOW I would not put this down to any one thing (such as as the LP recorder as opposed to the playback), but if you look at the waveforms that Ian expanded you will see that it is not only higher but also bifurcated, which suggests a 2nd harmonic.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: eric.w on 2017-08-05 00:55:04
It would be nice to see a better DR meter. Just brainstorming here but maybe something with a multiband compressor that tries to "brickwall" the music, taking an average of how much compression was applied in each band, and weighing the bands using equal loudness contours to give you a final DR number?
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: greynol on 2017-08-05 01:00:08
I don't see how that would work when you can compress a triangle wave just as easily as you can a sine wave.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: magicgoose on 2018-04-06 13:45:05
I really doubt that a "better" and "backwards compatible" DR meter is even possible.
At least not with the current problem statement (guesstimate the official DR score after undoing a linear filter with completely unknown characteristics). Well, if it can be solved by some calculus magic, it could be defined as "find a reversible linear filter (which must be relatively close to the identity filter — nothing extreme like long reverb, sharp highpass, etc.) which will fold the signal into one with minimum possible DR score" and then that DR score would be the answer. I guess this must be impossibly hard, but maybe someone who knows math better can add something?

Also perhaps it could work with a completely different metric, but it will measure a different thing which won't necessarily have a perfect correlation with the "official" DR on digital records. It will probably need to eschew peak levels (because they are changed after filtering) and compare some "short-term loudness" with long term loudness, but then it would be very insensitive to clipping (unless it's really extreme) and this is not what we want for digital records.
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: lvqcl on 2018-04-06 15:02:33
but then it would be very insensitive to clipping (unless it's really extreme) and this is not what we want for digital records.

Why? If we want to measure dynamic range, why should we care about unrelated things?
Title: Re: TT Dynamic Range meter "lies" about vinyl's dynamic rang
Post by: magicgoose on 2018-04-06 15:51:36
I'd say that clipping is related (it's a degenerate special case of limiting with zero attack time and zero release time, and limiting is a special case of dynamic compression) but… you might have a valid point here too.
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