Filter Self-Oscillation: What and Why?

Filter self-oscillation occurs as a result of resonance (a type of feedback) taking the electrical "noise" inherent in a synthesizer and feeding it back right at the filter's frequency cutoff point, resulting in a pure sine wave of that frequency. It can be useful as an additional analog oscillator on your synth and gives you another way to go about making music. In particular it can be useful for kick drums, basses, and sound effects, as well as giving you variations of noise. You can also blend the filter's self-oscillation with your existing oscillators.
Here are some notes for the patch "Laboratory Birds" used in this video as applicable to the Novation Peak and Summit (and surely replicable on many other synths):
Low pass filter: 130
Resonance: 121
Amp envelope: 10-74-40-63
Mod envelope 1: 72-41-21-63
Filter envelope depth: +15
Reverb time: 23
Reverb level: 43
Distortion: 42
Modulation matrix slot 1 source: Lfo1+; destination: VCALevel; depth: -10
LFO1 Rate: 177
Modulation matrix slot 2 source: Lfo2+; destination: Lfo1Rate; depth: +7
LFO2Rate: 122
Modulation matrix slot 3 source: Lfo3+; destination: FiltFreq; depth: -18
LFO3 Rate: 64
Modulation matrix slot 4 source: Velocity; destination: FiltFreq: depth: -24

[@xdendordx]

Pretty overlooked area of synths imo! Alex Ball played a gorgeous whistling filter patch in one of his Juno videos and I was stumped at recreating it on my Neutron until I realised I could keytrack the filter and just turn the oscillators off - adding noise to a low pass filter really gives it a vintage whistling grain and switching through the high-pass/band-pass modes gives different character too :)

[@pjamesbridge]

I agree, it could seem like a gimmick but it's a really powerful and fun option! Thanks for commenting

[@MatheusRobis]

crystal clear explanation, thank you

[@pjamesbridge]

Thanks for watching!

[@ianwatson4240]

WOW!!!!!
Making sounds using the noise floor! I wasn’t aware that I even had one until now!!!
More fantastic techniques. Thanks for sharing. Really inspiring.

[@pjamesbridge]

Now you have a another synth to work with! ;-) Glad it's inspiring. Thank you!

[@michaelbacon5278]

I loved this! The world needs more bitesize synth sound design tutorials like this. Also, you've got the whole Bob Ross thing going, very chill. Hope there will be more videos to come. I'd love more tips on patch design.

[@pjamesbridge]

Thank you! Bob Ross was great so I appreciate that. And hopefully one of these days I'll be able to produce a few more short tip videos. Glad it was helpful! Many of the ones in my Novation Summit series might be useful even if you're using a different synth.

[@totfosk]

I had no idea about this. Thanks a lot James for the explanation !! (L)

[@joserancel6255]

So good explained!!! Thanks !!!!

[@pjamesbridge]

Glad you liked!

[@orellronnbeck7340]

great video, ma guy

[@pjamesbridge]

Thank you!