Re: Is higher oversampling ratio better in signal fidelity in digital world?



Thinking in the time domain, as you lower the sample rate you increase the
digitization (Your sampled sine wave will start to look like a square
wave). Clocking that data through a DAC at the same rate will produce
strong harmonics (3rd 5th 7th etc). You can't regenerate the original sine
wave out of a DAC no matter what digital reconstruction filtering you use
if the playback rate is too slow. The output of a DAC will always start
digitizing and producing harmonics as you lower the sample/playback rate,
unless you have exceeded the full power bandwidth of the DAC or have
analog filtering after the DAC.

Thomas


Just to debate a little with myself (slow day). A soundcards playback and
recording rates are typically independent of each other. Playback being much
higher. So reconstruction filtering is possible. If the playback rate
equaled the recording rate you would notice the effects I was trying to
explain.


.

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