draft: false
Name: Impermanence
short-description: A 0.75-second stereo looper whose Chaos knob re-slices the take every time it moves, into a shimmer reverb.
summary: |
  Record 0.75 seconds of stereo audio, then play it with a single **Chaos** knob. Every movement re-cuts the loop:
  more slices, reordered, reversed and pitch-scattered as Chaos rises. A still knob holds the loop exactly;
  a moved knob throws it away for good, with no undo and no presets. Three layers of different lengths phase
  against each other into a shimmer reverb whose tail rises in octaves and animates as its decay knob opens. Tap the switch **down** for Rhythm mode, where slices
  step to a clock on Pulse In 2.
Language: C++ (Pico SDK + ComputerCard)
Creator: Matt Allison
Version: "0.4.2"
Status: Released
License: MIT
date-created: 2026-09-22
date-updated: 2026-09-28

contact:
  social:
    github: https://github.com/mrmattallison

uf2:
  - path: UF2/impermanence.0.4.2.uf2
    name: Impermanence 0.4.2

tags:
  - looper
  - granular
  - effect
  - reverb
  - generative

panel:
  inputs:
    - id: AudioIn1
      name: Record In L
      type: audio
      description: Left record source (both sides when Audio In 2 is unpatched)
    - id: AudioIn2
      name: Record In R
      type: audio
      description: Right record source
    - id: PulseIn1
      name: Record
      type: pulse
      description: Starts a 0.75-second take; a second pulse during the take ends it early. Unplugging doesn't disturb the loop
    - id: PulseIn2
      name: Clock
      type: pulse
      description: Locks loop timing to the clock without changing pitch; in Rhythm mode each beat plays the next slot. Unplugged or stopped, the last tempo is held
    - id: CVIn1
      name: Chaos CV
      type: cv
      description: Adds to Chaos in Texture mode (moving it re-cuts the loop); ignored in Rhythm mode and with the switch up
    - id: CVIn2
      name: Wet/Dry CV
      type: cv
      description: Adds to reverb wet/dry, in every switch position
  outputs:
    - id: AudioOut1
      name: Out L
      type: audio
      description: Left output, after the shimmer reverb
    - id: AudioOut2
      name: Out R
      type: audio
      description: Right output, after the shimmer reverb
    - id: PulseOut1
      name: Layer 1 Cycle
      type: pulse
      description: Pulse at the end of each layer 1 loop (the whole take)
    - id: PulseOut2
      name: Layer 3 Cycle
      type: pulse
      description: Pulse at the end of each layer 3 loop (the 2/3-length layer); 3 against 2 with Pulse Out 1
    - id: CVOut1
      name: Wander
      type: cv
      description: Slow, smooth random voltage, 0 to about +5V; patch to CV In 2 for self-fading reverb
    - id: CVOut2
      name: Envelope
      type: cv
      description: Envelope follower on the loop, before the reverb

controls:
  switch:
    up:
      name: Levels
      description: Main / X / Y set the levels of layers 1 / 2 / 3; Chaos and reverb hold their last values (the reverb keeps sounding)
    middle:
      name: Perform
      description: Main = Chaos, X = reverb decay, Y = reverb wet/dry. Main fully anticlockwise clears the buffer; turning it back up records a new take
    down:
      name: Perform
      description: Same knob jobs as middle (Down is momentary)
    tap:
      name: Texture / Rhythm
      description: Tap down to toggle between free-running grains (Texture) and clocked percussive slices (Rhythm)
  knobs:
    - main: { name: Chaos, description: "Position sets how wild a re-cut can be; movement triggers a new one" }
      x: { name: Reverb Decay }
      y: { name: Reverb Wet/Dry }
    - when: { z: up }
      main: { name: Level 1, description: Whole-take layer; picks up only after passing its last value }
      x: { name: Level 2, description: 3/4-length layer; picks up only after passing its last value }
      y: { name: Level 3, description: 2/3-length layer; picks up only after passing its last value }
  leds:
    - display: list
      items:
        - { id: LED0, name: Record / re-cut, description: On while recording; flashes on each re-cut }
        - { id: LED1, name: Rhythm mode }
        - { id: LED2, name: Layer 1 loop end, description: Mirrors Pulse Out 1 }
        - { id: LED3, name: Layer 3 loop end, description: Mirrors Pulse Out 2 }
        - { id: LED4, name: Wander level, description: Blinks with LED 5 while a knob is catching up }
        - { id: LED5, name: Envelope level, description: Blinks with LED 4 while a knob is catching up }