The Filter- Minimoog Filter Self-Oscillation

[@seemikehack]

This is the clearest explanation of self-oscillating filters I've yet found. Thank you so much for this video!

[@Kaei7]

thank you for posting this. i always thought self-oscillation in filters was somehow related to feedback. very well explained and informative!

[@Muzikman127]

I believe you were right actually. If I understand it correctly, this behaviour is caused by feedback within the circuit itself. The "resonance" feature of this filter is itself based on controlled feedback - it's feedback of the filter's output going back through itself that causes it to resonate, and so when you push it into "self-oscillation" (when the output is above a certain level), it will "sing" at its resonant frequency all on its own, from its output (at its resonant frequency) being fed back into itself. You actually could think of this as pretty similar to holding a microphone to a speaker cabinet and getting that "eeeeeeee" sound, the difference is, with this circuit, we can control the resonance frequency precisely and produces pitches that we actually want (with the keyboard itself when "keyboard control" is enabled). Whereas with a microphone next to a speaker, it's going to feedback at whatever resonant frequency/frequencies are naturally present in that system (often a pretty high and unpleasant squealing one haha). But that's a scientific explanation of how the phenomenon occurs, and not really representative of how it feels to interact with it at this level. So even though it is _caused_ by feedback, you don't really interact with it at that level, or need to understand the basis of the mechanism, in order to use and enjoy it. You would only need to understand the specifics of the mechanism if you were building your own resonating filter/oscillator circuit I think really

[@Kaei7]

@@Muzikman127 I'm not too sure about that, friend. According to the explanation on the video, the pitches we hear are produced by a standing wave (frequencies that "sync" together in such a way that their higher amplitudes happen to meet a single point, increasing the total amplitude by a lot at that particular point), and that would result from the high-frequency emphasis. I could be wrong, though. I'm far from an expert.

[@lincolnmicrophonellc]

Fun! Visuals/graphs of filters etc oscillators while talking would be so nice! Great content

[@Nerdimtar]

Excellent! Thank you for the crystal clear explanation!

[@jt_via]

This is great, thank you!

[@ARBB1]

What an interesting phenomena.

[@Feldspar__]

The Q stands for Quack.

[@gasolineandwine]

Amazing little well known trick. Sucks that the scaling is not a 100%, that is a very sweet sounding sine wave, but it ends up going both flat and sharp as you move around the keyboard. Another little known trick: you can fake an envelope modulating the pitch of an oscillator by adding a bit of envelope modulation to the filter, basically moving the pitch of the resonance as you play, similar to what you can do with a Prophet's oscillator being modulated by the filter env.

[@infohnie]

Mr Marc. Thanks for this video!

[@robbru3112]

Am I right in thinking that this effect is dependent on the noise floor of the analogue gear? As in that's what the filter is boosting when OSC1 is bypassed? I've tried recreating a similar effect digitally and found that there has to be some noise present - you can't use a filter to boost nothing, if you see what I mean.

[@theycallmeken]

Digitally it will be different but on the analog side, all analog filters will be able to do this.

[@Muzikman127]

right, in order to "feed back", you need some signal present. In an analogue circuit though there always will be though

[@frullmusic]

works identically on Softube's Model 72, which i suppose is a testament to the accuracy of the emulation

[@ericprimeau363]

Very useful explanation! Thanks!

[@ToniJXN]

Perfect explained

[@cipotebionico5417]

Amazing video! I was proving this in the Arturia's emulation, but these tricks doesn't work very well. I can get some noisy sounds and a little bit of modulation, but nothing else. I'm mixing this with a vocoder and a chorus and it has a diabolic dark ambient voice. Thank you!

[@gloverelaxis]

brilliant breakdown, thanks so much

[@bscenefilms]

Outstanding! Thanks for this!

[@thepostapocalyptictrio4762]

Works good with the Grandmother too!

[@theycallmeken]

Crystal clear explanation!

[@nickpelkey]

hey Mr. Timbre - ine Man well we could call you Mr. Timbre-sine.. just have the s silent.

[@tieukhavu8832]

Hammond organ emulator