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A comment on Diodes Hate It – Clipping with DSPs. Parent comment

Re:Diodes Hate It – Clipping with DSPs by fluoridation on Thursday December 22, 2022 @03:27PM (#34098198)
>It's important to note that if you take a sinewave and clip it, then sample it, you'll still get aliasing because you'll still have a big infinitely fast step somewhere, which is why audio equipment is so big on having steep lowpass filters before and after digital (or, sampled, at least) bits.

Ah-ha. Gotcha. So my intuition was more or less correct. It's not that clipping in digital is especially susceptible to aliasing, it's that when people clip in analog they brickwall the signal to get rid of the harmonics.

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Re:Diodes Hate It – Clipping with DSPs by Gordonjcp on Thursday December 22, 2022 @03:52PM (#34098510)
Exactly, and if you synthesize a signal in discrete time you must take care to bandlimit it by calculating what it would be if you'd already brickwall filtered it.

You can't create a naive sawtooth (for example) and *then* filter it because the damage has already been done. That being said, the "supersaw" oscillator in the Roland JP8000 generated a bunch of naive saws and *highpass* filtered them just below their fundamental to remove the gurgly "beat note" from aliased partials.

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