OP-1 Field: how do you disable local keyboard while keeping MIDI out? (Local Off equivalent)
Hi everyone,
I'm using my OP-1 Field as part of a custom MIDI chord setup and I can't figure out how to disable the local keyboard sound while still sending MIDI out.
What I'm building: I have a Monome Norns running a custom Lua script that emulates a chord. The signal flow is:
- I press a key on the OP-1 Field
- The OP-1 sends the note via USB-MIDI to the Norns
- The Norns builds a full chord (e.g., I press C → it generates C major, or Cm7, or whatever extensions I've selected)
- The Norns sends the chord back via MIDI to the OP-1
- The OP-1 plays the chord through its own synth engine
The problem: the OP-1 plays both the originally pressed note (from local keyboard) AND the chord notes from MIDI in. I only want to hear the chord. I need the OP-1's synth engine to play (so I can't just unplug), but I want the local keyboard NOT to trigger sound, only the MIDI input should.
On most synths this is called Local Off. I've dug through the menus and the only MIDI-related thing I can find is the CTRL submenu, but I can't tweak my synth when I'm in this control mode.
What I've tried from the Norns side:
- Sending a note_off back to the OP-1 right after receiving the note_on → kills the local sound, but also kills the OP-1's key tracking, so when I release the key no note_off is sent and the chord rings forever
- Sending CC 120 (All Sound Off) right after the note_on → no audible effect at all, which suggests the OP-1's local audio engine isn't reachable via MIDI CCs (separate voice pool from MIDI-in)
So I'm convinced this has to be done on the OP-1 side. Does anyone know:
- Is there a hidden Local Off setting on the OP-1 Field? Maybe in a sub-menu I'm missing?
- If not, is there a SysEx command or some other trick that achieves the same thing?
- Has anyone built a similar setup and worked around this?
Any pointers would be hugely appreciated. Happy to share the Norns script when it's done it's a fun way to use the OP-1 as an Orchid-style chord instrument.
Thanks!