Robin Vincent
I wrote a thing about filters - it's everything you'd want to know https://moltenmusictechnology.com/a-beginners-guide-to-synthesizer-filters/ #filters #synths #eurorack
A Beginners Guide to Synthesizer Filters

The different types, modes and forms of filters in your synth or Eurorack can be confusing. Let me take you through the basics of how these filters differ and give you some thorough comparions.

Molten Music Technology
Jul 24, 2023 at 4:13pmWeb
Show threadforestineJul 24, 2023
@molten This is great! I have encountered a few people who go "I don't think anybody needs a filter. All it does is *take the sound away*" and i facepalmed myself into the sun
Show threadStewartvmJul 24, 2023
@molten
Good read. Thanks
Show threadBill GribbleJul 24, 2023
@molten Really like this write up, especially the subjective filter descriptions. It’s a bit more technical, but your intro might discuss the differences between “linear” (only applying gain to frequencies) and “nonlinear” (wave shaping or distortion) filtering, and how the filters you describe are “mostly” linear but have nonlinear aspects that can give a lot of the flavor near the edges.
Show threadRobin VincentJul 24, 2023
@bgribble thanks. I’ve never heard of those two terms applied to a filter. Do you have any sources I can look into?
Show threadBill GribbleJul 24, 2023
@molten the wikipedia pages for “linear filter” and “nonlinear filter” are a pretty mathy overview. The gist of it is that linear filters can be described completely (for any input) by a frequency response. Low pass, high pass, bandpass, notch are all linear filtering operations. Wave folding, distortion, clipping and other common signal shaping techniques are not linear because the “frequency response” is different for different input signals. Real filters are crucially a bit nonlinear.