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Re: Y'all missing something important there.

I know what you are saying about noise but there is a difference between the digital and analog case. In this case if you want to look at the quantization as producing phase and amplitude errors (and for signals at low levels [a few bits] but above the noise floor the theoretical phase and amplitude resolution is still relatively poor) and you want to view these errors as noise then the noise is not random. It is completely correlated to the signal in that this theoretical noise has a fixed and exact relationship to the signal and a function of both frequency and amplitude. Of course there is the random noise component is there too from other parts of ths system, but these days a typical pro system would have a white noise level will below 1 bit in a 16 bit system (for a typical 2V system 1 bit is 61 uV). Random noise is not that huge a problem for perception either - we are very good at distinguishing signals that are not correlated as separate entities.

I guess that was the point of this dither discussion is by adding random noise you can mask the correlated noise.

I guess what I am trying to get at is the graph in that FAQ is a good example, BUT it does not tell the whole story... the truth is amplitude and phase resolution decreases as the signal level decreases so you cannot simply look at the graph and say there is no issue with either of these. Judging by the level of the signal from the axis it was using 15 of the 16 bits (if that was indeed the quantization level). Doing it at 20 Khz was good because it represents close to worst case frequency wise although the example is using close to best case bitwise, the problem is the worst case is also approached as the signal level drops (fewer bits) even at lower frequencies.

Don't get me wrong - I have heard systems with 16 bit CD front ends that boggle my mind at the level of resolution and tonal accuracy. I am relatively convinced that 16/44.1 is enough for storage (as long as you use really good methods of being faithful to the data on playback).

It just seems that the vast majority of CD systems I've heard, at that includes a lot of really high end stuff, are missing something that seems easy to attain on a realtively mediocre analog system. Maybe its all down the the filters.

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