draft: false
Name: XHT Card
short-description: A playable deep-note-inspired stereo chord swarm with manual
  scrubbing, one-shot movement, delay, reverb, CV, pulse, and optional MIDI
  control.
Language: C++ (Pico SDK + ComputerCard)
Creator: Adrian Vos
Version: 0.1.0
Status: Beta
License: GPL-3.0-or-later
date-created: 2026-07-11
date-updated: 2026-07-12
Editor: none
demo-link: https://www.youtube.com/watch?v=76RNe7uglP4

tags:
  - synthesizer
  - stereo
  - effect
  - midi
  - midi-host
  - cv
  - clocked
  - workshop-computer
summary: >
  XHT Card is a synthesised deep-note-style gesture rather than a bundled
  sample.

  Main sets the note position and one-shot destination. The momentary down
  switch

  resets the note and launches a one-shot from the start toward the current

  destination. CV2 also participates in destination control. P2 can clock
  stepped

  movement through the note. X controls delay and Y controls reverb.


  CV1 input transposes pitch. CV Out 1 mirrors note position unless CV1 is

  patched, in which case CV Out 1 becomes pitch. CV Out 2 always mirrors note

  position. P1 gates the note when patched and leaves the note sustained when

  unpatched.


  The separate MIDI build adds MIDI note input, CC1/mod-wheel destination

  control, sustain pedal on CC64, and MIDI note output of the current chord.

  MIDI clock is ignored.
panel:
  inputs:
    - id: AudioIn1
      name: External Audio Left
      type: audio
      description: Mixed into the left output before effects.
    - id: AudioIn2
      name: External Audio Right
      type: audio
      description: Mixed into the right output before effects.
    - id: CVIn1
      name: Pitch Transpose
      type: cv
      description: Transposes the current note position. When patched, CV Out 1
        reports pitch instead of position.
    - id: CVIn2
      name: Position / Destination
      type: cv
      description: Controls note position and the one-shot destination; scaled so 0-5V
        controller sources cover the full travel.
    - id: PulseIn1
      name: Gate
      type: pulse
      description: Gates the audio when patched. In the MIDI build, also gates MIDI
        output when patched.
    - id: PulseIn2
      name: External Clock
      type: pulse
      description: Clocks stepped movement through the note and overrides the one-shot
        while clocked.
  outputs:
    - id: AudioOut1
      name: Left Output
      type: audio
      description: Left channel with delay and reverb.
    - id: AudioOut2
      name: Right Output
      type: audio
      description: Right channel with delay and reverb.
    - id: CVOut1
      name: Position / Pitch
      type: cv
      description: Mirrors note position unless CV1 is patched, then outputs pitch.
    - id: CVOut2
      name: Position
      type: cv
      description: Mirrors the current note-position state.
    - id: PulseOut1
      name: Note Gate
      type: pulse
      description: Mirrors the current note gate; with P1 patched it follows P1.
    - id: PulseOut2
      name: Clock Mirror
      type: pulse
      description: Mirrors the P2 input pulse.
controls:
  switch:
    up:
      name: Octave Up
      description: Raises the note by one octave.
    middle:
      name: Normal Octave
      description: Normal pitch range.
    down:
      name: Reset / One-Shot
      description: Momentary reset that launches the note from the start toward the
        current destination.
  knobs:
    - main:
        name: Position / Destination
        description: Manually scrubs the note and sets the one-shot destination.
      x:
        name: Delay
        description: Controls delay amount/time character.
      y:
        name: Reverb
        description: Controls reverb amount.
  leds:
    - display: list
      items:
        - id: LED0
          name: Note Position
          description: Brightness follows the current note position.
        - id: LED1
          name: Delay / Main Position
          description: Main-build brightness follows X delay; MIDI-build brightness
            follows Main position.
        - id: LED2
          name: Envelope
          description: Brightness follows the audio gate/envelope.
        - id: LED3
          name: Reverb / MIDI CC1
          description: Normally follows Y reverb; the MIDI build briefly shows recent CC1
            destination control.
        - id: LED4
          name: P1 Gate
          description: Shows Pulse In 1.
        - id: LED5
          name: P2 Clock / USB Role
          description: Shows Pulse In 2 activity; in the MIDI build, also indicates USB
            host or device mode when idle.
host:
  usb:
    - name: USB MIDI Device
      role: device
      description: Connects to a DAW/computer for MIDI notes, CC1, sustain, and MIDI
        note output.
    - name: USB MIDI Host
      role: host
      description: Connects directly to a USB MIDI controller when the card boots in
        host mode.
  notes: |
    The MIDI build boots as either USB host or USB device, not both at once.
    For direct USB controller use, connect the controller before powering the
    card. Pressing reset alone may not force USB role renegotiation.
contact:
  social:
    github: https://github.com/soveda