Do materials alter frequencies and speed?

There is an implicit inference involved when one tests using pure sine waves, and then *infers* the results about audiophilic listening. It is probably best to remove this inference step, and--if one wants to make conclusions about what we perceive when we listen to music--then we should test these perceptions *with music.*

The point is not simply academic: as reported in the Journal of Neurophysiology (http://jn.physiology.org/cgi/content/abstract/83/6/3548) and cited in lay context here http://www.ocf.berkeley.edu/~ashon/audio/Ultrasonics.htm, measurable brain physiological response can be measured in individuals when exposed to music with a high pass filter of 22kHz. It is an impressive study, using special recording equipment, speakers with a flat response to 100kHz, baseline measurements for controls, electroencephalograms (EEG), positron emission tomography (PET), and measurements of cerebral blood flow to detect brain response. The PDF is available: well worth reading.

There is no explicit support for or against differences of 0.1dB or 0.25dB at 22kHz being discernable--I'll leave it to the reader to make his/her own inferences from what is explicitly tested.

Besides the importance of musical context, the study also found that short 15-20 second clips were not enough. Subjects listened for 200 seconds in much of the testing, and these longer listening sessions were required for a response to be noted.

This does lend some support to the old audiophile adage that you really have to sit and listen *for a while,* and then--you can't quite explain it--but there really may be a reason why you prefer A over B.

Listening tests - I do this at every CES. I have some 11 AWG ZIP and I swap it with my speaker cables. I do the same with IC's and digital cables. The listeners hear the difference every time.

Steve N.
Empirical Audio
Manufacturer

Audioengr: Everyone can claim to hear differences that don't exist, at least according to Rsbeck and the data that he cites. That's why i want him to perform such tests for himself, even if they are "flawed" in his eyes. This way, he can be in the same boat as the rest of us i.e. first hand experience either "proving" his past theories wrong OR at least causing him to question such teachings and not accepting them as "fact" rather than a hypothesized theory based on limited research.

After performing such tests and hearing the differences, which i'm confident that he will, he'll either have to question those "facts" or his own aural senses and processing center of the brain. Personally, i know which one i would believe if i conducted such a test and was easily able to identify one product from another. This is true even if others that i used to trust laughed at me and stated that my first-hand experiences were based on "flawed" test conditions. Sean
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PS... I picked Nordost to compare to zip cord for obvious reasons. That is, they share a high nominal impedance, neither of them is "radical" in terms of electrical characteristics, etc... At the same time, their sonic characteristics are different enough to produce opposite tonal balances, which is the most obvious difference that one can notice. Anything else would be a matter of subjectivity and harder to discern for an unskilled listener. I'm NOT saying that Rsbeck is an unskilled listener, only that i wanted to assure a "positive" test result under these specific circumstances.

0.25dB down at 20 KHz!!! I am crushed.

It is funny to see how many times the same things are repeated over and over in this thread. You guys just love being on the merry-go-round no matter what way it turns! whatta riot...