John Curl's Blowtorch preamplifier part II

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[snip] The same problem can be found even better by listening to the 30ips full track master tape vs a digitized version of the same master tape by just adding the AD-DA converter to the output of the master tape recorder. You know, A or B. Here, ONLY the digital problems are ADDED. Please everyone, try before you decide.

There is at least one well documented test that tried to show this, the (in)famous Digital Challenge with Stanley Lipschitz and Ivor Tiefenbrunn. The full story is on the Boston Audio Society website.
They inserted or bypassed a Sony F1 PCM in the source line. The change was inaudible, until at a certain point Lipschitz noted that there was a slight difference in noise level between the two situations (the F1 had a higher noise floor). Once he realized that, he scored 100% there after. But the others, inclusing Mr Tiefenbrunn, who relied only on the difference (if any) in the music, scored no better than chance.

jan didden
 
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There is at least one well documented test that tried to show this, the (in)famous Digital Challenge with Stanley Lipschitz and Ivor Tiefenbrunn. The full story is on the Boston Audio Society website.
They inserted or bypassed a Sony F1 PCM in the source line. The change was inaudible, until at a certain point Lipschitz noted that there was a slight difference in noise level between the two situations (the F1 had a higher noise floor). Once he realized that, he scored 100% there after. But the others, inclusing Mr Tiefenbrunn, who relied only on the difference (if any) in the music, scored no better than chance.

jan didden

Exactly as expected. ALL electrical processing will add some noise to a signal. In this case it surely adds no more than was added to the original tape by the recordeing process to begin with which means that had a digital tape recorder been substituted for the analog recorder, the total noise including the A/D + D/A converters would have been lower than the analog tape recorder alone. Even the added noise is a small price to pay for the elimination of every other form of audible distortion including rumble, acoustic feedback, wow, flutter, harmonic distortion, IM distortion, not to mention pops and clicks inherent in the vinyl record playback system. Had digital recordings come first, vinyl when demonstrated later would have been considered an interesting curiousity but not taken seriously. It would be universally regarded as an anachronistic joke by comparison.

This points out another fact, that the valid audible test for distortions introduced by an electrical signal device whether it is a preamplifier, wire, or A/D + D/A converter combination is not A versus B but A versus A bypassed. How would the blowtorch preamplifier stand up to that test I wonder?
 
Ivor was a 'fool' to be 'trapped' like that in a listening test that is set up to generate 'null' results, unless one 'cheats'. Ivor has had to live that one bit of overconfidence in his own listening ability for many years.
This is WHY I do NOT do ABX tests. I can't pass them, either. Neither can John Atkinson, or just about anyone else.
Are we deaf, but arrogant? Are we 'fools' to believe in our own listening comparisons? Some here, will tell me so, and more often than necessary. However, I just muddle on, seemingly getting good reviews for some reason, and many happy customers. I guess it is just 'dumb luck' with a few measurements added in.
 
Are we deaf, but arrogant? Are we 'fools' to believe in our own listening comparisons? Some here, will tell me so, and more often than necessary. However, I just muddle on, seemingly getting good reviews for some reason, and many happy customers. I guess it is just 'dumb luck' with a few measurements added in.

No violinist I know of chooses a violin by blind test, neither any pianist nor any other musician.

It seems to me that those people insisting on blind tests don't trust their own listening ability. Possibly some people are fearing Placebo Effect so much that it freezes their listening ability. In reality, Placebo Effect can be neutralized without blind tests, definitely without ABX tests. Possibly, other people deny their listening ability because of it cannot be proved by the scientific means they know.
 
It seems to me that those people insisting on blind tests don't trust their own listening ability.

If that statement is supposed to be logical, then an equally logical statement would be "It seems to me that those people against blind tests don't trust their own listening ability." Or further, that those people that are against blind listening tests are stressed out ninnies because they are fearful that they won't be able to find differences when there aren't any.

You can accuse people that you don't agree with with any physical, emotional, or mental fault you want. But maybe you should look in the mirror.

It is a mystery to me why some can justify that a test that eliminates all variables except for one is inherently faulty. The pat argument is that the test doesn't do that. The switcher is to "blame". Well simple, get rid of the switcher and move the same interconnect between components. Fast switching is to "blame". Well simple. Don't use fast switching. There is no rule that blind testing requires fast switching. Listen A for a week. Listen to B for a week. SIMPLE!! Is this TOO logical???
 
I 'warned' you Joachim. Keep up the good thinking, but please don't expose yourself here with it. It causes too much of a problem, because it promotes criticism by others. Many here look for the 'loopholes' rather than the essence of your opinion. Trust me, it happens almost every time I try to say something here.
 
Long Term listening is The Absolute Criterion...

What are the typical conditions of formal ABX testing ????.
Through long audio experience I am well able to discern and describe reasonably subtle differences quickly and reliably on music and systems and environment that I am well familiar with...for REALLY fine differences I may require multiple AAA-BBB-AA-BB-AB plays of particular passages on music that I know intimately to isolate and define sonic subjective differences.
Then after that comes longer term listening over multiple tracks/albums/genres that can extend to hours or days to properly establish subjective opinions.
Can it be that typical ABX testing of FINE differences is fundamentally flawed because it does not meet the above conditions ????.

Dave.
 
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Ivor was a 'fool' to be 'trapped' like that in a listening test that is set up to generate 'null' results, unless one 'cheats'. Ivor has had to live that one bit of overconfidence in his own listening ability for many years.

This is WHY I do NOT do ABX tests. I can't pass them, either. Neither can John Atkinson, or just about anyone else.

Are we deaf, but arrogant? Are we 'fools' to believe in our own listening comparisons? Some here, will tell me so, and more often than necessary. However, I just muddle on, seemingly getting good reviews for some reason, and many happy customers. I guess it is just 'dumb luck' with a few measurements added in.

This is a very revealing statement.
Unfortunately, some will find it amusing while others might mistake it for being insightful.
 
Joachim, good to hear from you. Both you and I know what high quality vinyl can do, but many here never will, nor should they, given what they want to invest their time and money on. I still haven't mounted the 'new' SL cartridge. My vinyl playing is limited at the moment, and I have other priorities. They had some good vinyl playback at CES, but nothing TRULY outstanding.
Listening tests are akin to something like a 'religion', dressed up as 'science'. The arguments are a matter of OPINION and BELIEF.
The problem is that BOTH sides can be 'proven' with little doubt. All you have to do is to SELECT the type of test that you want to believe in.
If you select ABX testing as the reference standard, then everything that I have said here for the last 5 years will be of no use to YOU.
If you select your own ear's opinion in simple A-B listening tests, then what I have said here can be very valuable, perhaps more valuable than many other threads and websites.
However, trying to explain to someone who is locked into either camp, appears to be pointless.
It is 'something' about the ABX type test that makes it virtually impossible to not confuse what you are hearing so that you cannot hear differences between components. Please remember that the MUSIC is changing, as well. This could be a MAJOR KEY in why there are problems. It would be like trying different wines blind, during a forced change in the food that you must eat before another taste and selection. Sort of like onions, then, pate, then sauerkraut, etc. and comparing a good wine with 2 buck chuck.
That might be fun! But I doubt that I could tell the difference. I have enough trouble in general tasting tests. Maybe someone here could do it.
 
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Your expectation is I will find nothing. Mine is I will find something and it often will not be what I am looking for. I presume you find nothing upsetting about the experiment.

No, but I will not do much criticism from now on. I expect you to find something and not be able to explain it and that is where it will be left.

As a general comment, I don't think some folks around here appriciate the level of sophistication that has been around for decades in the precision instrument domain. I could go on forever nuclear research, ultrasound, CAT, PET, geoscience. To think that audio taxes the limits of collective engineering wisdom is unbelievably fatuous and a fantacy. Good solid engineering practice works in audio as well as anywhere else.
 
If that statement is supposed to be logical, then an equally logical statement would be "It seems to me that those people against blind tests don't trust their own listening ability." Or further, that those people that are against blind listening tests are stressed out ninnies because they are fearful that they won't be able to find differences when there aren't any.

Does this view of yours include also violinists, pianists and other musicians?
 
To think that audio taxes the limits of collective engineering wisdom is unbelievably fatuous and a fantacy. Good solid engineering practice works in audio as well as anywhere else.

There may be a difference.
Some engineers are satisfied with "solid engineering practice" only, without bothering to listen to the outcome. Those engineers may miss the core issue with audio design.
 
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