In article , Tim S Kemp
wrote:
Stewart Pinkerton wrote:

Whaaaat? That's rubbish, any modern 44.1k ADC is ruler flat to at
least 20kHz.

Never measured it, but the waveforms of perfectly audible stuff8khz
will be somewhat distorted at 44k sampling compared to higher rates.

Only if the sample values are incorrectly and incompetently used by the DAC
and filtering arrangements used for signal reconstruction.

From information theory you can use formal mathematical methods to prove
that the entire waveform shape is represented by the sample values provided
the Sampling Theorem was satisfied when the samples were recorded. This
means the DAC and reconstruction filter can recreat the waveform *without*
the 'distortions' you assume exist.

FWIW as well as having looked at, and used, the theory I have also:

1) tested players and looked at the output. The results show your
assumption is incorrect. Hence I *have* measured it, and can say that the
results show you mistaken.

2) Produce a number of examples that I've used in my undergrad lectures for
years. These also show that your assumption is incorrect.

3) published a book that deals with these issues in detail. Copies now
available in paperback. ;-

Slainte,

Jim

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