Thorsten, someday I hope that we can 'prove' what we hear. Until then, I personally will design my stuff the best that I can, using every means at my intellectual disposal to avoid 'compromises'. So far, so good. Someday, when we find out 'more' it may be easier to relax some requirements and concentrate on what really works.
PMA, I respectfully disagree that SACD or even double SACD is PERFECT. My experience with it with identical sources is that really quality and well set up vinyl is somewhat better, like it is more 'human' as far as the voice and not a copy. This is my experience, BUT I am willing to learn. IF you, PMA, are not using a really expensive MC cartridge properly adjusted, in your comparisons, then maybe you will not find the same result.
The trap here is that you decide before you are conciously aware that you did it. Of course you decide first and then you lift your finger. But there is a timelapse between your decision and you becoming aware of 'deciding', so it only LOOKS as if you start the action before deciding.
A nice analogy is normal speech. You don't really talk by thinking: 'now I will say this, now I will say that...'. Well, you do, but you don't do it conciously. Generally speaking (pun not intended) you only know what you are going to say the moment you hear yourself speak. Of course the words don´t come out randomly - they are carefully selected to bring across whatever point you want to make. But that selection and composition process is outside your conciousness.
It's only a very small fraction of the work your brain does, that comes up to your conciousness. People who are not familiar with these processes tend to assume that when they are not conciously aware of something, it doesn't exist and/or it didn't happen.
jan
Too much prejudice and suspicion, IMO.
I have good results with "blackbox" A x B comparison. Listener is not aware of content of blackboxes, so there is no reason for expectations.
A-B-X is wrong according to many experts, as it confuses the listeners and creates similar traps you are describing - the listeners are aware of the fact that they ARE supposed to find the difference, and this fact suppresses their ability to concentrate well on the listening process.
I have good results with "blackbox" A x B comparison. Listener is not aware of content of blackboxes, so there is no reason for expectations.
A-B-X is wrong according to many experts, as it confuses the listeners and creates similar traps you are describing - the listeners are aware of the fact that they ARE supposed to find the difference, and this fact suppresses their ability to concentrate well on the listening process.
That's the level I get at the listening chair with 1V RMS into both speakers . So a very convenient reference for me.
Yet it mysteriously works for detecting level, frequency response, clipping and recovery, phase, polarity, compression, data compression, speaker polar pattern, noise floor... Wow, things are just soooooo mysterious!
Black box can be a good method, but the experiments have to be controlled properly- in the world of the High End, that's anathema.
The physicist Leo Szilard once announced to his friend Hans Bethe that he was thinking of keeping a diary: "I don't intend to publish it; I am merely going to record the facts for the information of God." "Don't you think God knows the facts?" Bethe asked. "Yes," said Szilard. "He knows the facts, but He does not know *this version of the facts*." - as related by Freeman Dyson in his wonderful book _Disturbing the Universe_
Thanks,
Chris
Thanks,
Chris
I'm with you, PMA. I am impressed that you have found what I have found, independently. If you and I are wrong, then we are wasting our time. I TRIED ABX testing 32 years ago, I wrote about it in a series of LTE's in TAA back then. I DIRECTLY confronted Dr. Lipshitz with criticisms of his 'scientific' test of differences at the time. Did I get any thanks? NO!
It must be understood that there are 2 kinds of mistakes: One that denotes differences that don't exist, and the other that removes differences that DO exist. It is the second kind of mistake that is often ignored. You and I, PMA should compare notes. I still have them.
It must be understood that there are 2 kinds of mistakes: One that denotes differences that don't exist, and the other that removes differences that DO exist. It is the second kind of mistake that is often ignored. You and I, PMA should compare notes. I still have them.
A quote from Rod Rees (and Shaeffer) from 'The Saga of the GOLDEN EAR versus METER READER' TAA 4/79 p.22
"We hope now that the Saga of Golden-Ear and Meter-Reader is ended. Neither is correct, and yet neither is wholly wrong. Each merely errs commensurate with his own built-in observer bias. And as for the audiophile trying to make a little sense of it all, he should listen to both points of view and listen to his own perceptions. After all, none of us can do anything but hear what we hear."
Drs. Rees and Shaeffer teach at Western Washington University, Bellingham Wa
"We hope now that the Saga of Golden-Ear and Meter-Reader is ended. Neither is correct, and yet neither is wholly wrong. Each merely errs commensurate with his own built-in observer bias. And as for the audiophile trying to make a little sense of it all, he should listen to both points of view and listen to his own perceptions. After all, none of us can do anything but hear what we hear."
Drs. Rees and Shaeffer teach at Western Washington University, Bellingham Wa
Yet it mysteriously works for detecting level, frequency response, clipping and recovery, phase, polarity, compression, data compression, speaker polar pattern, noise floor... Wow, things are just soooooo mysterious!
Black box can be a good method, but the experiments have to be controlled properly- in the world of the High End, that's anathema.
Were are problems with proper control, since record quality, switching device quality, listener experience, other components of the system, all together form "measurement setup". This provides a big space for ambiguity, since precision of such setup can not be technically specified, especially records and listeners. Very easy to make resolution of such "setup" bad or good, correspondingly, this resolution can be adjusted depending on tests purposes.
Using of such setup superpose definite part of listener's personality on the conclusions made. One case is an untrained listener, another case is experiences audiophile.
If, for instance, early Mark Levinson would proceed from bad recordings and opinions of untrained listeners, humanity would never got his early masterpieces.
On the other hand, one canadian speaker manufacturer uses extensively proper A-B-X tests, and I owned one of their top products. Better not to remember what I thought about their testing group.
Right you are, Vlad. It is IMPRESSIVE to find what learned professors ignore when it comes to audio quality, when making their ABX comparisons. I had to correct Dr. Lipshitz, in print, on several occasions. Did I get a 'thanks'? No, not a word.
For example, would YOU use a 30 year old Shure phono cartridge, which inherently contains a 4 pole roll-off just above 20KHz for maximum slew rate determination? How about loading the same Shure phono cartridge with 1/2 the recommended resistive load? (reducing the output by 6dB at 15KHz). Well?
For example, would YOU use a 30 year old Shure phono cartridge, which inherently contains a 4 pole roll-off just above 20KHz for maximum slew rate determination? How about loading the same Shure phono cartridge with 1/2 the recommended resistive load? (reducing the output by 6dB at 15KHz). Well?
One observation. I participate in a local so-call club of audiophiles, and their activity is mainly exchange of CD recordings. Many used CD's bought in Europe or USA are offered for sale, official releases produced by EMI and other companies alike.
What I mentioned, quality of 95% of CDs is almost not sufficient to distinguish between my best amp and Gainclone, while with few % of CDs, or with special audiophile CD releases, the difference is huge. So, mainstream requirements to equipment level has affected greatly the recording industry. Were is a person in UK, who offers 1 million USD to those who will distinguish between "correctly engineered amps" in A-B-X test. Possibly he knows how to arrange test, when nothing will be distinguishable.
What I mentioned, quality of 95% of CDs is almost not sufficient to distinguish between my best amp and Gainclone, while with few % of CDs, or with special audiophile CD releases, the difference is huge. So, mainstream requirements to equipment level has affected greatly the recording industry. Were is a person in UK, who offers 1 million USD to those who will distinguish between "correctly engineered amps" in A-B-X test. Possibly he knows how to arrange test, when nothing will be distinguishable.
Last edited:
Almost certainly he does. I can give you the secret, but you have to promise not to tell.
1. Both amps have low distortion (<0.1%) and noise.
2. Neither amp is clipping.
3. Levels are matched.
4. Frequency responses are matched to within 0.1dB between 20Hz-20kHz.
5. Both amps have low source impedance so as to achieve #4 with the speaker load.
If you do those things, the million dollars is safe. Remember, mom's the word!
However, if you now compare (say) two different levels of data compression, any careful listener will walk away with the prize. That DBT stuff is insidious- it seems to allow the detection of all sorts of things except fashion.
- Status
- Not open for further replies.