Rupert Neve, the famous designer of high end mixers contends that the frequency response of his equipment must be flat up to 100 kHz in order to sound completely natural. There may be something about the dynamics of real life sounds that hearing tests using sine waves don't account for.
What is the range of human hearing?
In the simpler days, let's say those of Audio magazine to provide an easy enough reference point, that range was said to be from 20 hz to 20 Khz. In fact, that was only good in younger people with good hearing. The linearity was far from perfect wihtin that range also, and middle-aged people, sometime after a life of working in a noisy environment, had measurable loss in the higher frequencies; 12 to 14 Khz being about as good as one could hope for at that age. Obviously the sampling rate debate has something to do with my question. I have read recently that humans may hear up to 23 Khz. This startled me, hence my question. I am not looking for theories or for explanations as to why cartridges should have a frequency response way over human hearing capabilities, or filtering in digital systems or whether tweeters should do more than tweet by sounding great to the family dog also. An answer on point is all I wish for.