Download
& Install

Before You Start

Back Up First.

• Back up your OP-1. Put it in disk mode (Shift + COM, then the DISK key, T3) and copy the whole drive to your computer. Tape, synth, drum, album, all of it.
• Original OP-1 only. Not the OP-1 Field.
• You need Python 3. A Mac already has it. On Windows get it from python.org.
• This is at your own risk. It has run on two OP-1s. The bootloader stays stock, so a bad flash can be redone, but nobody is promising anything.

Install

Six Steps.

• 1. Get the official firmware. Download op1_246.op1 from teenage engineering's OP-1 downloads page. It has to be 246, the last one for the original OP-1.
• 2. Make the modded file. Put op1_246.op1, the patch and apply.py in one folder, open a terminal there and run python3 apply.py op1_246.op1 op1-mod-1.0.op1patch. It checks that the firmware file is the exact one the patch was made for, writes a new .op1 file next to it and verifies it. If the check fails it writes nothing.
• 3. Put the OP-1 in upload mode. Power off and unplug USB. Hold COM while you switch it on. Press 1, then plug in USB. A small drive called OP-1 shows up.
• 4. Copy the new .op1 file onto that drive and eject it.
• 5. Press COM on the OP-1. That starts the update. Don't pull the cable or power off. It takes several minutes.
• 6. Power cycle. It should boot to the tape like always. Your tape and sounds are untouched.

Read This One

Going Back
to Stock.

Stock firmware doesn't know the new engine, effects or LFO. If any synth sound, drum sound or the master is using KEYS, ITER, CRUSH, BELL, MOON, MIMIC, LINGER, SPIN CYCLE, FILTER or the TIDE LFO when you flash stock, the OP-1 stops at boot with an "Invalid synth patch" message.

• Before you go back, switch every sound that uses one of those to a stock effect or LFO. Then flash the official op1_246.op1 the same way as above.
• If you forgot, you don't need a factory reset. Flash the mod again, it boots, switch the sounds, then go back to stock.
• The TRACK sequencer, chord mode, scales and the Shift latch don't have this problem. Stock just ignores them.

Using It

Where Things Are.

• Chord mode and scales. In synth mode press T2, then hold Shift. Shift + the low F key turns chords on and off, the white keys from G up pick the shape. The scale root and type are on the same screen. SCALE OFF means every key plays as normal.
• KEYS. Shift + a sound key, folder KEYS, for the TINE, REED and CLAV presets. Start from a preset.
• CRUSH, BELL, MOON, MIMIC, LINGER, SPIN CYCLE. In the effect list (Shift + T3) with the stock effects.
• TIDE LFO. In the LFO list (Shift + T4). Hold Shift and the four knobs become SHAPE, PHASE, SYNC and SKEW.
• TRACK sequencer. In the sequencer list with the stock ones.
• Shift latch. Press any knob to give the knobs their Shift job without holding Shift. Press again, or change page, to drop it.
• MIDI CCs. 16-19 engine knobs, 24-27 attack decay sustain release, 28 play mode, 29 portamento, 40-43 effect knobs, 44-47 LFO knobs, 48 LFO shape, 50-53 master effect knobs, 56-59 the LFO's Shift knobs. Channel 1 unless you changed it. The full chart is in the manual.

Something broke, or it works great? Tell me on Discord. Which OP-1 you have and what you were doing when it happened is what I need.

This is free and it stays free. If you want to say thanks, the tip jar is here.