op1r – OP-1 custom firmware

Turns the original Teenage Engineering OP-1 firmware R246 (op1_246.op1) into the op1r custom firmware, and manages the synth engines and effects on your OP-1. Everything runs in your browser: your firmware file is not uploaded anywhere.

1. Synths and effects

Ticked ones are installed. Sounds that use a missing one play the stock iter / filter until it is back.

Own plugin files (.op1p, e.g. from make_plugin.py; installed over USB):

Warning: a plugin is program code that runs inside the OP-1 with full access. Only install plugin files from people you trust. A faulty or malicious plugin can crash or lock the OP-1, damage your sounds and tapes, or break the device.

2. Firmware file

For the OP-1's bootloader update mode, or when the OP-1 runs stock / an older op1r: get the original op1_246.op1 from teenage.engineering, drop it below (takes about half a minute), then download the result or send it over USB (section 3).

3. OP-1 on USB

An OP-1 running op1r updates over USB MIDI (SysEx) without the bootloader: only what differs is sent, then the OP-1 asks – T1 restarts and applies, T2 cancels. Needs a browser with Web MIDI (Chrome, Edge).

The original firmware can always be flashed back. Use at your own risk. Source, changelog and command-line patcher. Like it? Buy me a coffee on Ko-fi.