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Re: No, there isn't.

I agree no dither is no good.

But I still have more questions:

Quoting Mark earlier in this thread...
"As the original paper states the dithered waveform does show statistical correlation to the sampled signal so it does have artefacts that are harmonically related to the signal, but the error signal sounds like white noise and the power spectrum shows no such artefacts above the increased noise floor. I believe this last rider is significant."

Which basically states that all the correlated noise from quantization is now buried in the white noise - ie the error signal "sounds like white noise" because of the dither. This makes total sense from an engineering point of view.

Now, the question becomes how does the ear/brain deal with it. Maybe someone can answer this question.

If I combine a pure fundamental frequency and white noise, what do I hear - a pure tone and hiss.

If I try the ultimate example of a correlated signal, a pure fundamental and some of its harmonics and some white noise - I will hear a single tone (which will sound different than the pure one) and hiss.

If I bring up the level of white noise to mask all the harmonics but not the fundemental, what do I hear? Either (a) the pure tone and hiss or (b) the different sounding tone and hiss.

If the answer if (a) the spectrum analyzer results where the correlated noise is buried in the white noise floor is good enough to say we have solved the problem.

If the answer is (b) then the analog/digital case is different because the correlated noise may still have some effect on perception even if it is buried in white noise. That paper does not deny there is correlated noise within the noise floor - they just say it all sounds like white noise. The fundamental difference between digital and analog in this case is the presence of this correlated noise - even with dither. Whether there is any practical significance I don't know but even with dither there is a difference from the pure theoretical point of view in that the encoding is a source of correlated noise (even with dither which is there to mask this effect) in digital and it is not in analog.

One a related note...back to perception - if a hear a mono recording (so localization isn't a clue) of many sounds I haven't heard before with the same fundmental and different evenvelopes I can still pick out distinct sounds. How do I do this? Do we know? If I can actually do this without it being learned it means that a property of the signal itself must contain this information - and it is very likely that it is our strong sense of recognizing correlated signals and our great ability at separating uncorrelated ones and separate entities that allows us to do this.

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