> Fortunately even cheap A/D converters nowadays are very good.
> ...
> Nothing to do with data compression. Losses in the process? Way
> below imperceptible.
Agreed. Across all the bits, linearity can't be maintained, but over
six or
eight bits, it is good enough. For instance, a 100% error in the sixth
bit equates to about 3% distortion and it is always better than that.
Having experimented with ADC's, it is difficult to get rid of
crosstalk from the digital circuits back into the analogue input. This
is where cheaper ADC's tend to fall down, but "dither" is added to the
last three bits, ostensibly to prevent quantisation noise, but I
suspect it is there whether you want it or not. :-) Dither "averages
out" the quantisation noise of the least bits through "stochastic
resonance", which even Wiki apologises over. (Yes, I did have to look
it up) :-)
I haven't looked at 24 bit recordings on my affordable Tascams, but I
suspect that the least bits are noisy. For a start, no analogue input
is likely to have a signal to noise ratio of 138dB if only because
that takes it beyond thermal noise.
BTW if you want to hear quantisation noise, listen to an 8 bit digital
signal. It sounds like a kazoo.
David
David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce
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