summary: "A tape loop, eating its own tail. The buffer is the tape: one head assembly records input + feedback over what came round from the last rotation. Tape length, varispeed (repitches the whole loop), freeze, momentary reverse, splice-tick pulse out, position-ramp CV out. Companion prototype for a physical 1/4\" tape loop rig."
short-description: A tape loop, eating its own tail.
Name: Ouroboros
Language: "C++ (Pico SDK + ComputerCard)"
Creator: "Jason Moore"
Version: "0.1"
Status: "Released"
date-created: 2026-07-24
date-updated: 2026-07-24

panel:
  inputs:
    - id: AudioIn1
      name: Audio Input
      description: Input to the record head
    - id: CVIn1
      name: Tape Speed CV
      description: Varispeed, 1V/oct, adds to Y (total range +/-2 octaves)
    - id: CVIn2
      name: Feedback CV
      description: Adds to the main knob
    - id: PulseIn1
      name: Freeze Gate
      description: High = freeze — the record head lifts and the loop just spins
    - id: PulseIn2
      name: Reverse Gate
      description: High = the tape runs backwards (playback only)
  outputs:
    - id: AudioOut1
      name: Wet Output
      description: The playback head
    - id: AudioOut2
      name: Dry Output
      description: Input thru — mix with the wet output yourself, or hard-pan
    - id: CVOut1
      name: Envelope Output
      description: Envelope follower of the wet output, 0..+6V
    - id: CVOut2
      name: Tape Position
      description: A 0..+6V ramp once per rotation — a loop-synced LFO
    - id: PulseOut1
      name: Splice Tick
      description: A 10ms pulse each time the splice passes the head — clock things to the tape rotation
    - id: PulseOut2
      name: Freeze State
      description: High while frozen

controls:
  switch:
    up:
      name: Freeze
      description: The record head lifts; the loop spins forever and input is ignored
    middle:
      name: Echo
      description: Sound-on-sound with regeneration
    down:
      name: Reverse
      description: Momentary — the tape runs backwards while held, playback only
  knobs:
    - when: { z: any }
      main:
        name: Feedback
        description: 0 to ~112% — unity around 3 o'clock, the last stretch runs away into tape saturation
      x:
        name: Tape Length
        description: ~100ms to ~4s at centre speed, square law; lengthening splices in a copy of the loop so the bed keeps playing
      y:
        name: Tape Speed
        description: Varispeed, +/-1 octave, centre = normal — Doppler-shifts everything already on the tape; slow tape is longer and darker