Tim, > I don't think it's psycho-acoustics, distortion creates more harmonics, > that's physics CMIIW. "CMIIW" --- OK: While it is well-known that distortion creates more frequency components, in a classic experiment done in 1924 by Wegel and Lane [1], it was shown that due to the nonlinear processing done by the inner ear, additional tones could be heard provided that the intensity was loud enough. That there are psychophysical effects which result in "louder produces more harmonics" has long been established. If there are also other nonlinear effects beyond this (nonlinear processing by the brain), then there may also be psychoacoustic effects that result in "louder produces more harmonics." This is very likely, not nonexistent. -------------------- [1] R. Wegel and C. Lane. The auditory masking of one pure tone by another and its probable relation to the dynamics of the inner ear. In Physics Review, volume 23, pages 266-285. Cited in Curtis Roads, The Computer Music Tutorial, MIT, 1996.
