A MIDI-in, MIDI-out note transposer. Play in a comfortable key and sound in the band's key, or drop a keyboard part an octave for a bass line. It has one main knob, an octave knob and an on/off switch, so it also works as the brain of a simple one-knob MIDI pedal.
How it behaves
- Held notes are safe. Turning the knob, changing octave or switching off while you hold keys never leaves a note hanging downstream: each release always ends the pitch its note started as.
- Notes pushed out of range are dropped. A note that would land below the lowest or above the highest MIDI note is not sent, and neither is its release.
- Channels are kept. A note arriving on channel 4 leaves on channel 4.
- Notes only. Control changes, pitch bend and program changes are not passed through.


