High-end audio
"William Sommerwerck" wrote in message
...
The purpose of dither is to sufficiently randomize the quantization
error that it's no longer correlated with the signal. This requires
noise with a P-P value of two quantization steps (I think). The
background noise of an analog signal is unlikely to be at this level.
No, it doesn't require that level of noise exactly, it requires that
level as a MINIMUM. That amount of noise OR MORE will properly
dither the quantization.
This Bothers Me. My gut reaction is No, that's not right. Noise at that
level "looks like" part of the signal. How can it properly randomize the
quantization errors?
William, you don't seem to understand that when dither is properly added, it
hits the quantizer looking just like the rest of the signal. I would chalk
that up to a failure of logic.
With a lot of DAW software and stand alone resamplers, you can turn dither
off during conversions that should have it.
I've confirmed experimentally that adding identical noise to the signal
before conversion has the effect as turning on the dither.
I don't know if you read my earlier post about dither helping sound quality
in pure analog systems, like class B amplifiers with the bias slightly
misadjusted. If so, you missed its meaning.
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