MIDI Reference
OOOO Digital Tape Loops accepts MIDI note input and plays each matching loop polyphonically, like a tape-based keyboard. MIDI notes change loop playback speed and pitch together. The plugin does not produce MIDI output, and there is no built-in MIDI CC map.
Supported messages
Only note-on and note-off messages are handled. Events are applied at their exact sample position inside the audio block.
| Message Type | Function | Description |
|---|---|---|
| Start or retrigger a note head | Every loop whose MIDI CH setting matches the message channel receives the note. Velocity values 1–127 all use the loop's note envelope; velocity does not currently change gain. |
|
| Release a note head | Starts the matching note head's Note Release stage on every matching loop. |
|
| Release a note head | Treated as note-off. | |
| Ignored | CC, pitch bend, aftertouch, sustain pedal, program change, MIDI clock, and other non-note messages are not handled. |
Per-loop channel routing
Selection does not decide which loop receives MIDI. Each loop independently filters incoming notes with MIDI CH, so one note can play several loops at once.
| MIDI CH | Behavior | New-loop default |
|---|---|---|
| Ignore note input on every channel. | Second and later loops | |
| Accept note input from channels 1–16. | First loop | |
| Accept notes only from the selected channel. | — |
Pitch and polyphony
Middle C (MIDI note 60) plays at the loop's current rate. Each semitone changes that rate by the usual equal-tempered pitch ratio.
| MIDI note | Rate multiplier | Result |
|---|---|---|
| 0.5× | One octave below the loop's current speed and pitch. | |
| 1× | The loop's current speed and pitch. | |
| 2× | One octave above the loop's current speed and pitch. |
Note behavior
Each loop has one note-head slot for every MIDI note from 0–127. Different notes are polyphonic; repeated note-ons for the same pitch reuse that pitch's existing head.
| Loop parameter | Default | Behavior |
|---|---|---|
| Note Mode: Mellotron | Enabled | A newly activated pitch starts at the most recently tracked note-head position. Before any note head has played, it starts at the transport position. |
| Note Mode: One-shot | — | A newly activated pitch starts at the active loop's start boundary, then follows the current forward or reverse rate. Despite the name, the head wraps and continues until note-off and release. |
| Note Start % | 0% | Adds a random offset between 0% and the selected percentage of the active loop length when a new note head starts. |
| Note Attack | 2.0s | Time to rise from the current envelope level to full level. |
| Note Decay | 0.05s | Time to move from full level to sustain. |
| Note Sustain | 100% | Level held while the note remains on. |
| Note Release | 2.0s | Time to fade from the current level after note-off. |
Implementation notes
Effective note rate = loop rate × 2(note − 60) / 12, clamped to −4×…+4×. Reverse loop rates remain reverse.
Note heads are independent of the loop's transport head. They can sound while transport playback is stopped, and they are mixed with the transport when it is running.
DAW host automation is separate from MIDI input. OOOO Digital Tape Loops exposes automatable plugin parameters, but it does not assign incoming CC numbers to them.