Every electronic circuit has an analogous mechanical circuit whose motion is governed by an equivalent differential equation. Analog synthesizers are electronic circuits, so analog synthesizers have mechanical analogues -- analog analogue synthesizers.
The heart and soul of any classic subtractive synth is its filter section. Most use a ladder circuit of RC filters. This takes a raw waveform with a lot of harsh high frequency content (like a sawtooth or triangle wave), and turns it into something more musical.
The heart and soul of any classic subtractive synth is its filter section. Most use a ladder of RC circuits to make a low-pass filter (LPF). It takes a raw waveform with a lot of harsh high frequency content (like a sawtooth or triangle wave), and turns it into something more musical.


Two rungs (pictured) give a two pole filter, and four, well, four. I'd like to make a mechanical analog of one such rung. If things go well, I can make multiple and chain them together, just like in the electronic circuit.
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@@ -53,7 +53,7 @@ Finally, instead of measuring the output voltage across the capacitor, we'll be
All in all, here's a simple sketch of the main components for one stage of the filter. If all goes well I'll build multiple of these.