Funny that RH from Asolute Sound just had an editorial report on measurements and how objective vs subjective listening.... take a look:
http://www.avguide.com/forums/blind-listening-tests-are-flawed-editorial
I thought the rebuttal was more accurate in describing the reality:
First of all, you are correct, "indistinguishable" does, indeed, mean that NO audible difference exists between 16-bit, 44.1 KHz digital and the High Resolution formats. I have been doing a lot of recording lately and I have had ample opportunity to test 16-bit, 44.1KHz digital quantization against both 24-bit, 96KHz and 32-bit (fp), 192 Khz quantization. Playback directly from the computer (through the same DAC/ADC with which the recording was made) yielded no audible difference to a listening panel of 5 audiophiles. Also, no audible difference was detected between the high-resolution recording and the SAME recording output as 16-bit, 44.1KHz Red Book and burned to CD. The CD was also played back through the same DAC/ADC as through which the recording was made in order to keep variables low.
Secondly, you are wrong to characterize those who value double-blind or ABX testing as being mostly supported by "...Partisan hacks, bent on discrediting audiophiles. " I too was skeptical of the so-called "double-blind" test until I started to participate in some of them. My first encounter was with a group of audiophiles using a home-made ABX setup to audition two very high-end power amplifiers. It was bad enough when the tests revealed that no one could reliably tell when the controller (sitting in another room and switching or not switching amps every 30 seconds by the clock while a number of different types of music were played) switched or didn't switch or to which amplifier she had switched (she didn't know which was which either. Sometimes she would switch at the appointed time, sometimes not. We listeners never knew). The end result was that statistically, the 6 listeners got it right about 50% (give or take a few percentage points) of the time. In other words, blind chance. When the same experiment was repeated using one of the expensive amps and a much cheaper amp of similar power and the same results were obtained it did seem that all modern amps sound the same. This brings me to point three.
Scientists use ABX and double-blind testing for things other than audio (you mentioned pharmaceuticals) for a good reason. If such tests reveal no differences, its because there are no differences. Whether the device under test is a pair of amplifiers, a set of cables, or a 16-bit, 44.1 KHz digital recording vs. a 24-bit, 192 KHz digital recording of the same performance or a new "wonder drug". If the test is properly set-up and the results are that there is no NOTICEABLE difference between the two units in question (or the test subject and the control), then it stands to reason a difference which makes no difference is no difference at all. But something here strikes me as even more important. If the differences that we are talking about here are so subtle that a direct A-B comparison does not illuminate them, does this also not say that we are engaged in counting angels on the head of a pin (I leave it to you to decide whether these are "recording angels"javascript:emoticon('
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I don't pretend to be able to explain your European radio CODEC story, but obviously something was wrong if no one in a listening test heard a 1.5 KHz noise in the program material. Perhaps the panels weren't given more than a few seconds to hear each sample, I don't know, but it would seem to me that anyone would be able to hear a non-correlated 1.5 KHz tone in a musical performance if given ample time (no more than a few seconds) to focus in on it.
George Graves
