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Comment by Derbasti

14 years ago

You will still need a aliasing filter that cuts off between, say, 18 and 22.5 kHz to avoid aliasing noise. That is one sharp filter no matter how you look at it. You can use a high quality, long, linear-phase FIR filter, but you can't cheat physics: sharp filters necesserily introduce distortion, and such a sharp filter so close to the hearing threshold does not go unnoticed.

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Derbasti

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sjwright  14 years ago

I don't see how a sharp filter could be needed if the DAC is oversampling.

  • Derbasti  14 years ago

    Obviously. Analogue audio does not have a sampling rate. The ADC however can oversample all it wants, but if the output is 44.1 kHz, it needs an aliasing filter that cuts off at 22.05 kHz.