Bessel Filter for Oscillator Frequency Filter Modifier

Currently the Frequency Filter modifier for oscillators creates nasty ugly ripples in the waveform which can be an issue for anything that uses the amplitude of the signal, like FM or RM/AM or distortion, and visually it’s difficult to gauge how it’s adding to other waveforms if there’s layering in the oscillator.

Bessel filters better preserve the wave shape of signals, which seems like it’d be important for a wavetable synthesizer what relies on manipulating wave shapes.

I don’t mean to suggest that the current filter should be removed and replaced since there may be some quirky sounds that end up changing, but adding Bessel LP/HP/BP as additional styles would be nice. Naming the styles to convey the important characteristic in case someone isn’t familiar with, say, Bessel vs Butterworth, could be done like… default is Sharp and Bessel is Smooth? That’s how it’s done in FL Studio’s equalizer for LP/HP and I think it works well enough as a description there.

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Are you talking about the Low Pass and High Pass spectral morphs? I’m pretty sure those are operations on the overtone spectrum, successively removing higher (or lower, respectively) overtones. You can see this in the SP display. So they’re effectively brick-wall filters.

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i think it would be cool if there was a way to write FX using a compiled on the fly language like Reaper’s ReaJS, that way you can just code that filter yourself if you can find a snippet somewhere. So you could add filter types just by dropping a .txt file in the “filters” folder. (provided it’s formatted the right way)