Strudel: effects, signals and pattern internals

This module takes you from triggering patterns to performing them. In a real browser-based live set — a laptop, Strudel’s REPL projected behind you, no external synths or mixer — everything the audience hears is shaped by method chains on your patterns. The whole task is an evolving piece that breathes on its own: melody constrained to a scale so improvised edits stay consonant, a filter sweep riding a slow sine like an LFO, reverb and delay opening space in a drop, and periodic and probabilistic transforms mutating the material while you think about the next move.

Start supported: take a groove from the prerequisite module and bolt on one effect at a time, leaning on “lpf() applies a low-pass filter” and “gain() controls amplitude” as just-in-time references, then replace static values with continuous motion via “Strudel’s built-in signals (sine, saw, square, rand, perlin) continuously modulate effect parameters”. Next, add harmony with scale() and comma-built chords (transposed with add()), and layer variation with every, sometimes, and chunk. The final, unsupported step goes under the hood: write one method of your own with register(), and explain — using the Hap’s whole/part timespans and the appLeft/appRight structure-donation rules — why your combined patterns land where they do.

The required atoms are exactly what the capstone cannot be faked without: the five named effects, both signal atoms, the conditional-transform family, scale/chord/add for melodic material, and the internals chain from pure() through withValue to register(). Supporting atoms widen the palette — panning, off-echoes, ply rolls, polymeter, sample tricks like splice and loopAt, and deeper query-time internals — worth absorbing once the core piece runs, and natural next moves when the piece needs a second night’s worth of variation.

Runnable examples

Generated from the context/ instrument corpus by concept (redistributable idioms only). Do not edit — regenerate with gen-module-examples.mjs.

every-n-transform

s("bd sd hh cp").every(4, rev)

_{strudel-0028 · CC0}

d1 $ iter 4 $ sound "bd sn hh cp"

_{tidal-0045 · CC0}

sample-chop

s("breaks125:0").chop(8)

_{strudel-0020 · CC0}

d1 $ chop 8 $ sound "break:0"

_{tidal-0019 · CC0}

four-on-the-floor

s("bd*4")

_{strudel-0001 · CC0}

setcps 0.52

_{tidal-0044 · CC0}

reverb-space

s("cp").room(0.6).size(4)

_{strudel-0019 · CC0}

out: mix ~a ~b >> plate 0.3

_{glicol-0008 · MIT}

probabilistic-variation

s("hh*16").degradeBy(0.3)

_{strudel-0026 · CC0}

d1 $ degradeBy 0.3 $ sound "hh*16"

_{tidal-0025 · CC0}

adsr-envelope

note("c3").s("sawtooth").attack(0.01).decay(0.1).sustain(0.6).release(0.3)

_{strudel-0205 · CC0}

{ Saw.ar(220) * EnvGen.kr(Env.perc(0.001, 0.2), Impulse.kr(2)) * 0.3 }.play

_{supercollider-0013 · CC0}

polymeter

s("{bd sd, hh hh hh}%4")

_{strudel-0007 · CC0}

d1 $ sound "{bd sn, hh hh hh}%4"

_{tidal-0007 · CC0}

stereo-panning

d1 $ pan (slow 2 sine) # sound "hh*8"

_{tidal-0037 · CC0}

SinOsc s => Pan2 p => dac; -0.7 => p.pan;

_{chuck-0042 · MIT}

subdivision

seq [55, 82.5, 110, 82.5] & osc >> audio

_{punctual-0014 · CC0-1.0}

d1 $ n "0 .. 7" # scale "minor" # sound "arpy"

_{tidal-0030 · CC0}

formant-vowel

note("<c3 e3 g3>").vowel("<a e i o>")

_{strudel-0036 · CC0}

d1 $ note "c e g" # sound "supersquare" # vowel "a e i"

_{tidal-0035 · CC0}