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Can you provide links for these studies please?
When reading other discussions around the web, people have mentioned the following tests/studies, but I haven't been able to find them (and the discussions where I had seen them mentioned where often old, so the participants didn't respond). I also looked in the sticky topic with links to blind tests as well as the sticky topic with FAQs, but with no luck. Many of the links in those two topics are also more than ten years old and have since been removed.

So, here are my requests:

* Master tape vs. CD and/or hi-res (failure/success - I assume failure. I know of Bruce Botnik doing such a blind test (at 24/192) with other people present, and I know of mastering engineer Dave Collins doing it as well (at 24/88.2). I've also heard of someone in the 90s who offered a million dollars if someone could tell a master tape apart from a CD (Michael Fremer should be a millionare by now  ;)  ), but if you know of any "proper" studies, then please share a link  :)  )

* Master tape vs. vinyl (probably where vinylphiles preferred the vinyl transfer and/or succesful/unsuccesful blind tests between the two)
 - less important sub-request: vinyl vs. digital recording of the LP. I know of two good cases: One is the Spanish website Matrix Hi-fi, which actually also exists in English (the page with links to blind tests says Spanish only) as well as the one from Audio Asylum conducted by Mike Lavigne and John Elison. The latter was a blind test, but I don't know if everything (e.g. volume level) was controlled. The former didn't say if it was blind, but everybody agreed that the two sounded the same.)

* Null-test between digital audio with and "without" ringing (I found this on Archimago's Musings. Someone said this in a comment: "There is also little evidence of this ringing being present in the audio signal with null tests using actual music signals. The only eveidence you will find is a small 'peak' at the filter's cut-off frequency in the 'difference file' in this case. Any (small) differences in the audible band will be caused by phase or amplitude (FR) differences or distortion. Small FR and phase differences are not audible BUT very measurable by the way and caused by the filter or coupling capacitors in the chain." According to Archimago's images, a higher sample rate removes ringing in the audible spectrum, although Archimago himself seems to downplay any audible effects of this ringing)



I might ask for a few more studies, but this was all I could think of now. Thanks for your help :-).

  • pelmazo
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Re: Can you provide links for these studies please?
Reply #1
* Master tape vs. CD and/or hi-res (failure/success - I assume failure. I know of Bruce Botnik doing such a blind test (at 24/192) with other people present, and I know of mastering engineer Dave Collins doing it as well (at 24/88.2). I've also heard of someone in the 90s who offered a million dollars if someone could tell a master tape apart from a CD (Michael Fremer should be a millionare by now  ;)  ), but if you know of any "proper" studies, then please share a link  :)  )
This looks like a mixup of several different issues.

The first one seems to revolve around what a master tape actually is. Back in the old days when actual tape machines were still used, there were master tapes coming out of the mixing phase. They were then passed to the mastering engineer, where the material was processed according to the distribution medium. This was particularly important for vinyl, which has its idiosyncrasies that requires some specialised processing to make it suitable for being pressed onto a vinyl disk. The CD is simpler in this respect, but mastering still uses processing to optimise the perceived loudness, and make sure that the track sequence is presenting itself as a coherent whole. The output of this also used to be called a master tape, but in the case of a CD it would use the same format as the CD, namely 44.1/16. Nowadays, there typically is no tape involved anymore, it's all files on a data storage medium.

There was an offer of the well-known magician James Randi to pay anyone a million dollars who can prove his paranormal abilities in a properly controlled experiment. At one time it seemed that this was being taken up for a hifi cable test, but it didn't happen, and the parties then accused each other of foul play. I am not aware of a similar attempt involving master tapes, but perhaps someone else does.

So you should state more clearly what you are referring to.

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* Master tape vs. vinyl (probably where vinylphiles preferred the vinyl transfer and/or succesful/unsuccesful blind tests between the two)
Are you looking for a preference test? The fact that vinyl playback produces quite characteristic noises, means it is usually quite easy to distinguish between vinyl playback and tape playback. It is not that easy to remove this factor from the equation.

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* Null-test between digital audio with and "without" ringing (I found this on Archimago's Musings. Someone said this in a comment: "There is also little evidence of this ringing being present in the audio signal with null tests using actual music signals. The only eveidence you will find is a small 'peak' at the filter's cut-off frequency in the 'difference file' in this case. Any (small) differences in the audible band will be caused by phase or amplitude (FR) differences or distortion. Small FR and phase differences are not audible BUT very measurable by the way and caused by the filter or coupling capacitors in the chain." According to Archimago's images, a higher sample rate removes ringing in the audible spectrum, although Archimago himself seems to downplay any audible effects of this ringing)
Such a null test is a measurement exercise rather than a listening test. It involves subtracting two signals from each other which are supposed to differ very slightly. Are you interested in such a test, or are you trying to find evidence for the audibility of the difference? If it is the latter, the null test itself won't help you.
  • Last Edit: 10 January, 2017, 08:01:47 AM by pelmazo

Re: Can you provide links for these studies please?
Reply #2

* Master tape vs. CD and/or hi-res (failure/success - I assume failure. I know of Bruce Botnik doing such a blind test (at 24/192) with other people present, and I know of mastering engineer Dave Collins doing it as well (at 24/88.2). I've also heard of someone in the 90s who offered a million dollars if someone could tell a master tape apart from a CD (Michael Fremer should be a millionare by now  ;)  ), but if you know of any "proper" studies, then please share a link  :)  )

The far more relevant test is a test of a CD format file that was downsampled from a true high rez source.  Since excellent resampling freeware, high rez audio files and ABX testing freeware is so widely available, this test is one that nobody who is interested in the issue shouldn't do for themselves.

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* Master tape vs. vinyl (probably where vinylphiles preferred the vinyl transfer and/or succesful/unsuccesful blind tests between the two)

This difference is so audibly clear to this day that in the days when vinyl was all we had, there were literally 100's of people, more commonly known as Vinyl Mastering Engineers who usually had busy, well paid positions trying their best to minimize the obvious difference.

Everybody who worked in production knew many from copious personal experience, that audible perfection was impossible and that if you could eliminate vinyl and just listen to the analog master tape, you were generally a much happier listener. 

The only thing wrong with master tapes was they were impossible make perfect copies of, and when you tried to make copies at costs that were still many multiples of the incredibly low cost of making a LP (on the order of a dime for a LP), they were then way off the mark.

In the days when vinyl was all we had, the audible deficiencies were well known and already known to be impossible to totally audibly mitigate.  They are also trivial to measure and the measurements easily exceed known audible thresholds.  The idea that people would try to make a good master tape sound as bad as vinyl would make just about anybody who was engaged in LP production back in the day, puke.

In short there are no studies of this because they are about as interesting as studies of whether or not festering manure piles have an odor.

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- less important sub-request: vinyl vs. digital recording of the LP. I know of two good cases: One is the Spanish website Matrix Hi-fi, which actually also exists in English (the page with links to blind tests says Spanish only) as well as the one from Audio Asylum conducted by Mike Lavigne and John Elison. The latter was a blind test, but I don't know if everything (e.g. volume level) was controlled. The former didn't say if it was blind, but everybody agreed that the two sounded the same.)

The request is very vague and trivial. What constitutes a comparison of vinyl versus digital recording?  We already know that good CD-format or better digital is sonically transparent and undetectable, and we also know that it is impossible for vinyl or analog tape to be sonically transparent.  You can arrange these factoids in such ways as  to cover just about all of the possible meanings, so the tests are all trivial.

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* Null-test between digital audio with and "without" ringing (I found this on Archimago's Musings. Someone said this in a comment: "There is also little evidence of this ringing being present in the audio signal with null tests using actual music signals. The only eveidence you will find is a small 'peak' at the filter's cut-off frequency in the 'difference file' in this case. Any (small) differences in the audible band will be caused by phase or amplitude (FR) differences or distortion. Small FR and phase differences are not audible BUT very measurable by the way and caused by the filter or coupling capacitors in the chain." According to Archimago's images, a higher sample rate removes ringing in the audible spectrum, although Archimago himself seems to downplay any audible effects of this ringing)

Can anybody point out a good set of DBTs that were done by Archimalgo?

In short, the only really interesting questions relate to whether or not CD-quality digital is really as good as many find it to be.   This whole business of preference for vinyl is a meme that was created and widely speread once people realized how much better digital audio really was and how disastrous this was for people who a big investment in analog.  Once this took hold, additional promulgators of the meme joined in to capitalize on the potential profits from promoting The Big Lie.  The final stage was when people figured out that they could use The Big Lie to sell just about anything audio, which led to the current situation where there are anong other stupid things about 400 different DACs on the market, the vast majority of which actually can't be sonically distinguished from each in a good listening test, but there is now so much money to be made convincing people that they all sound different and better than each other.
  • Last Edit: 10 January, 2017, 08:57:32 AM by Arnold B. Krueger

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Re: Can you provide links for these studies please?
Reply #3
Sorry, I see now that I was being a bit vague in some of my requests. But thanks for your help, Arny and Pelmazo :-).

As for CD vs. master tape, what I meant was a blind test of a CD made from the analogue master tape, be it "mastered" or not. I am aware that back in the 80s (as well as now) there were albums that were mastered differently for vinyl and CD, so what I meant was just an analogue master tape (preferably commercially avaible material) transferred directly to CD with no further processing, EQ etc.

As for James Randi, this is not the challenge I was thinking of above. Although I have also seen similar tests like the following mentioned elsewhere, I read this on speaker manufacturer Harbeth's forum posted by a forum member:

"In 1997, TDK did offer 1 million dollar during a consumer show to anyone who could correctly identify the master tape, tape and CD in 10 successive trials. No one could. You can read about it in the Soundstage magazines."


As for the vinyl vs. master tape studies, yes I was looking for a preference test – as you say, hearing a difference between a master tape and a vinyl is usually easy, although I suppose tests where test subjects couldn't hear a difference might be interesting to read as well.
I'm okay with "lie" tests, such as the people conducting the test saying "one is vinyl, one is digital, what do you prefer?" when in fact one is an analogue master tape. Tests where they don't tell the test subjects which is which, but where the test subjects would then assume one must be vinyl and one must be CD would also be great - if they exist. For me this would be the proof you mention, Arny, that CD quality is really transparent.

As for vinyl vs. needle drop, then I would be happy to hear about more tests - especially academic papers, if such papers exists.


The comment from Archimago's website is not by Archimago himself but by a reader of his blog. Anyway, the null test I asked for would probably be a measurement to show if the result was actually null or not (probably not), and then perhaps a discussion or listening test as to find out if the ringing was actually audible – I assume it's not. The commenter said this measurement had been done, but I haven't been able to find this anywhere. As mentioned, Archimago actually showed with some pictures of measurements in that post that ringing was absent in the audible spectrum (he used 10 kHz tones) in hi-res, while present in CD quality. I took this to mean that oversampling hadn't been able to solve this issue in CD quality, although I personally don't think it's of very high importance (and Archimago seems to say the same). After all, if blind tests of hi-res vs. CD quality still shows nobody is able to hear the difference, then the ringing shouldn't/can't be audible either.


I'm convinced that CD quality is good enough, and I don't see any use for hi-res except perhaps for a few theoretical reasons (as above) that might be completely inaudible, but it would be nice to see some properly conducted studies that back up these things.