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RE: That clears up a lot!

Dear Morricab;

I appreciate the time and trouble you took in your long and civil post.

I think most of the things you are talking about can be summarized in two principal sections. First, regarding electronics, including CD players, you seem to think that there are all sorts of distortions besides the ones conventionally measured that affect the listening experience, and that mid-priced electronics exhibit more of these. The hard evidence simply does not support this. Comparing an inexpensive CD player or preamplifier, designed with flat response and low noise and distortion, with an expensive one possessing the same properties, does not yield any difference that shows up in a level-controlled blind test.

If the cheap component somehow flattened the stereo image, robbed the music of life or blurred the acoustic picture of the instruments, it would be easy to set up a system with good depth and "air" and hear the difference. To date, no one has managed to do this, and it has been tried with some extremely expensive stuff.

You claim that expensive gear "does less damage overall" to the sound, which assumes there is audible damage done by less expensive circuitry -- but you don't say what that is, or why in 75 years of amplifier design and research only the high-end designers have supposedly identified it and dealt with it. You are positing a new kind of distortion -- which just means any difference between the input signal and the output. This does not exist, which is why no test, using instruments or ears, has ever been devised for it. Audible damage should be audible, but somehow, when no peeking is allowed, it is not.

As for the digital section of the signal path, you mentioned the Meitner paper on jitter. This is an AES preprint, not peer reviewed, from 1991 (#3105). It does not deal with audible effects, and in fact says nothing about how jitter affects the audio output of a CD player. It only measures the jitter itself under different conditions and notes signal-responsive changes. Bob Adams (who was at the recent AES convention and is still a prominent digital circuit designer) was cited as a consultant for this paper. He later investigated the effects of jitter on the audio, and concluded that it was not a significant problem. This was in about 1996, as I recall, so the performance of conventional D/As was adequate at that time.

As for speakers, you advance the opinion that systems using cones and domes suffer too many ills to be sufficiently transparent, for a variety of reasons having to do with stored energy, various resonances, phase shift and so on. This picture is supported by the marketing literature of the makers of ribbons and electrostatics, but not by the actual physical behavior of the systems. (Did you know that the air within a quarter inch on either side of a KLH Nine's surface weighs a quarter of a pound? This observation comes from the late Henry Kloss, the "K" in KLH, who was a cheerful debunker of many of the myths surrounding ESLs.)

Besides, we performed a series of tests using a system that meets all your criteria as part of our experiment -- unless there is something about the very expensive system described at http://www.bostonaudiosociety.org/explanation.htm that you find unsatisfactory. The principal subjects for that part of the experiment -- the people who chose the music, set the playback levels, ran the player, determined when to repeat the music, and so on -- were the system's owner and his friends. That system sounded very good to me and to the subjects, but also failed to reveal differences in our test. If your assumptions about what goes on with speakers and electronics were correct, the difference should have been dramatic.

We are planning more tests with the high-end system later, which we will duly report. -- E. Brad Meyer




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  • RE: That clears up a lot! - EBradMeyer 10/23/0711:54:46 10/23/07 (0)

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