I found a really good book covering quite thoroughly the subject of psycho-acoustics ["An Introduction to the Psychology of Hearing" (Sixth Edition), by Brian C.J. Moore]. In it is a very nice, brief summary of "perceptual coders" such as MP3. I've attached a copy here in case anyone (besides me) is interested.
There is nothing in this book, however, about Spectral Band Replication, which as I understand it, contributes a major part of the bit-rate compression achieved by newer coders like that used in HD Radio. I asked the author if there is any psycho-acoustic basis for SBR technique, and he responded (!) that it's more of an engineering technique than a psycho-acoustic technique: For many sound sources, the short-term spectrum at very high frequencies can be predicted moderately well from the short-term spectrum at moderately high frequencies, and this provides a basis for reconstructing the very high frequencies with artifacts that are "not too bad." -- Clark2
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