• intensely_human@lemm.ee
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    5 months ago

    Nyquist, thank you.

    aren’t lost they fold into lower frequencies unless filtered out

    If by “fold into” you mean they add noise to and hence distort the readings on the lower frequencies, that’s correct. But that just takes it further from a perfect reproduction.

    • Hugin@lemmy.world
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      5 months ago

      Frequency folding is the term used in DSP no need for quotes. The Nyquist frequency is commonly referred to as the folding frequency.

      And yes frequencies above the Nyquist folding frequency alias into lower frequencies. A simple low pass filter prevents this however.

      Properly filtered digital sampling produced a more accurate reproduction of the frequency range with less distortion then an analog signal.

      • intensely_human@lemm.ee
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        5 months ago

        Also I used quotes to refer to your words, not to throw shade at a term’s validity. I use quote marks to quote.

        If by “x” you mean …

        Doesn’t mean the same thing as just randomly surrounding it with quotes in normal use means.

      • intensely_human@lemm.ee
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        5 months ago

        I don’t disagree that there’s noise in analog signals too, limiting their information capacity. But that’s coming from the limitations of our physical implementations’ quality, no?