🚀 go-pugleaf

Mathew Hendry (m.hendry@dial.pipex.com) has been known to utter the following:

: I know they are. The problem is that the definition of noise you gave implies
: that they are not.

The definition of noise that I gave was that noise in general is 
usually white noise, or random noise like white noise within the frequency 
spectra in which we are interested.
This is exactly what quantisation noise is, - noise within the spectra of 
the sampling system.

: : : These effects are not random, therefore by the above definition they do not
: : : constitute noise.
: : 
: : : These effects are heavily dependent on the input signal, therefore by the
: : : above definition they do not constitute noise.
: : 
: : They are also heavilly dependent on the speed of the A/D converter and the 
: : accuracy of  the internal D/A converter, and external effects such as noise 
: : which are picked up internally.

: None of these effects are random, other than external noise. Adding extra
: non-random effects to a non-random process cannot suddenly make it random.

Nonsense. The amount of time taken to convert an Analogue signal into 
Digital is completely random, especially when when the input signal is 
changing all the time. Unless of course you are using flash A/D 
conversion, which is AFAIK not what most audio sampling systems use.
The fact the the time taken to convert a signal is random, means that a 
random element is picked up during quantisation.

: Consider an ideal sampling/quantization process. For such a process the errors
: introduced are completely non-random, and completely dependent on the input
: signal, the quantization steps and the sampling rate. The definition of noise
: you gave therefore implies that ideal sampling/quantization is completely
: noiseless.

: So either your definition of noise is incorrect, and the ideal process _is_
: noisy, or it is correct, and ideal quantization is not noisy after all. Now
: which is it? Either one will invalidate some of your claims, but I'd bank on
: the former myself.

An ideal system implies that there is no noise or distortion, does it not?
That is why it is an ideal system.