Chris Hornbeck wrote:

Watkinson's The Art of Digital Video, 2nd ed. pg. 143-144 (sorry,
don't have The Art of Digital Audio handy): " the principles of
analog and digital dither are identical; the processes simply take
place in different domains using two's complement numbers which are
rounded or voltages which are quantized as appropriate. In fact
quantization of an analog dithered waveform is identical to the




hypothetical

Here's the problem. Assuming an infinite number of bits to be removed,
you're right; dither is necessary to truncate to N bits, like 24 or 16.
But they're saying that Analog is equivalent to infinite bit depth,
which is clearly impossible; an A/D convertor gets you some finite
number of bits. After it's done that, dither below its resolution buys
nothing. It just stays below that resolution, and rather than adding
information, it only adds noise.




case of rounding after bipolar digital dither where the number of
bits to be removed is infinite, and remains identical for practical
purposes when as few as 8 bits are to be removed. Analog dither may
actually be generated from bipolar digital dither (which is no more
than random numbers with certain properties) using a DAC."

Hopefully, I'll be shown to have misunderstood the above, and can go
back to my comfortable but fuzzy understanding of things before this
blasted thread started. Ignorance was bliss, and I'm too old to
study.

Thanks!

Chris Hornbeck "That is my Theory, and what it is too." Anne Elk