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feedback4 new

4-op FM norns engine, clone of Organelle Feedback4

undisclosed Imported automatically; the author has not disclosed AI use yet

install

In maiden's REPL (the >> prompt at the bottom of the editor), run:

;install https://github.com/jstefani/feedback4

Or add the splines catalog to maiden and install it from the project manager. Restart norns if the script ships a new engine.

readme from jstefani/feedback4

feedback4

4-operator FM synth for norns. Clone of the Organelle PD patch Feedback4: custom algorithm matrix (FM8 expert window), per-op ADSR, ratio, pan, and a frequency envelope sourced from any operator.

MIDI in. 8-voice polyphony. 25 factory presets from the original presets1.txt.

install

Copy to ~/dust/code/feedback4/ on the norns. New SuperCollider engine needs SYSTEM > RESTART once, then reload the script.

rsync -va --exclude .git --exclude pd . norns.local:~/dust/code/feedback4/

controls
E1 page: play / op1–4 / algo / macro
play E2 preset · E3 transpose · K1+E3 amp
op E2 ratio · E3 out · hold K2+E A/D · hold K3+E S/R · K1+E pan / env amt
algo E2 cell · E3 send amount (4×4 PM matrix)
macro hold K2 which · E2 dest · E3 scale · hold K3+E3 value
K2 tap tweak — walk the current patch a little (algorithm stays)
K3 tap randomize — new sparse algorithm, ratios, envelopes
panic PARAMS → all notes off

PARAMS also has tweak patch and randomize patch triggers.

architecture (from the PD patch)

Each operator is a phase-mod oscillator (phasor~ + cos~). The 4×4 matrix is how much each op writes into each other op's phase, including self-feedback (one-block delay, same as PD throw~/catch~).

ADSR is linear. Velocity scales the attack peak only; sustain is absolute. Attack / decay / sustain / release and output sliders are squared, then:

  • attack = sq * 300 + 0.5 ms
  • decay = sq * 1000 ms
  • release = sq * 2000 + 10 ms

Ratio is a free multiplier on the note frequency. Freq env adds (chosen op's ADSR * env amt) onto that ratio.

original

PD sources live in pd/Feedback4/. Organelle patch; desktop mother patch included for the original UI.

discussion

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