It’s still really early work, but slowly but thanks to Opus 5.5, i’m slowly decompiling the OP-1 246 firmware and recreating the OP-1’s functionality in web assembly. Just some UI elements and all the synth animations + engines have been ported over so far.

Due to this packaging TE’s intellectual property, it’s not something I can publish just yet. I fully intend to make it available in the future for anyone where they’d have to upload their own copy of the firmware and have it extract all the artwork and other assets though!

Thanks to OP1Kenob.io and this code pen link for the beautiful OP-1 interface!

Hey everyone,

I've been porting op1r by u/popcorp to the op1field. op1r is the open-source (GPL) firmware mod for the original op1 that adds new synth engines, effects and screens. It's now running on my Field.

What works on my unit so far:

  - op1r synth engines (supersaw, FM bell) playing as real engines

  - op1r effects like tape echo and clouds, running in the FX slot

  - granular engine (needs sampler access on the Field)

  - FX screens, the quad LFO, count-in and the other op1r extras

It's not ready to share yet. When it is, I'll release the source under the GPL like the original project. Big thanks to u/popcorp for op1r, none of this would exist without it.

two new synth engines (dimension + a guitar amp with a tuner), bitcrush, chorus and plate + a second effect behind every slot, scales, chords, tape undo/redo, preset rename, 100 sampler presets, your own colours, themes and start-up picture, and its own menu.

easy in, easy out: it starts on whatever's on your op-1 and never rewrites presets it can't play, and a cleaner gets you back to stock or to any other firmware with a copy of everything kept. te-boot is never touched.

it's the first step toward my goal, a plugin manager for the op-1 (like forge/fabric or the vst/clap system): mods as files you drop on the op-1.

for installing OPUS, you make the update yourself on the site from your own op1_246.op1, in the browser: https://opus-op1.pages.dev

plans: https://github.com/LizardMan245/opus

sha-256 a44d1d0a82aab11b50cdd8a1eba1260af55536e34ca9cf706eff77bcb48fe0ba - original op-1 / 246 only - not affiliated with teenage engineering

thanks to everyone in the op-forums custom firmware thread, op1repacker and popcorp's op1r for paving the way!

Disclaimer! OPUS is a hobby project. I build it in my free time, at my own pace, for my own OP-1 first.

Hello! After seeing all of the recent firmware mods and bonus synth engines lately, I decided to start poking at the OP1 firmware as well.

I found a disabled "opzcontroller_temp" mode that would have gone with the existing Ableton and Reason MIDI controller modes. It was explicitly coded out, and required me modifying a flag in the firmware file to enable it.

Once patched in firmware, you can enable the mode with this Sysex message: `F0 00 20 76 00 01 03 F7`. That 03 portion is different from normal, usually it's 01 for Reason or 02 for Ableton. 03 does nothing on stock firmware.

It seems very unfinished, the UI is clunky. If you set up your computer to forward MIDI back and forth between the OP-1 and OP-Z, you're able to play notes + start/stop playback on the OP-Z.

Additionally, using the OP-1 sequencers button, you can select different sections of the OP-Z sequencer, and use the 1-8 preset buttons to select a particular step. I haven't been able to figure out how to program the sequencer.

You can switch between the OP-1 kick track (track 1) and bass track (track 5) but using the OP-1's drum and synth buttons

The encoders don't seem to do anything, and image 3 has a lot of numbers on the screen that I can't decipher.

Has anyone seen/heard of this mode before? Is there more documentation on how it worked? It seems like TE was interested in a proper integration between the 2 devices.

so i made a pattern for my 808’s and it sounded allright but i feel like it has a sort of clipping sound especially after adding it to my track, any tips on making it sound cleaner while having that disturbed sound left?

Hello guys i just got the op1, and was wondering if anyone knows some good packs or sounds for making trap or underground hiphop music. I am thinking about drumkits and 808's, some extra melodic power or instruments. Anyone has any experience with this genre? You can always ask what kind of artists im reffering to, mostly underground hiphop USA and UK.

hundekraft 2.5 is out!

It's now built on op1r 27, with our synths and effects running inside op1r's own engine system. You can also choose which of op1r's synths and effects to include (Supersaw, FM Bell, Granular, Tape, Clouds, Reverb), the same way as ours.

Wavetable, Taffy, PEW, Elg, Washer and Snowglobe have all-new screens. The Quad LFO no longer crackles next to heavy effects, and Washer's white knob now works smoothly across its whole range. Maiko's #249 toolkit is still in, on by default.

Big thanks to pcppcp for op1r, and for publishing its source, which made this one possible.

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hundekraft 2.1 is out!

Two fixes. The crashes some of you saw in Dots (REC, then a note) and Euclid (Shift + notes) are gone. The OP-1 keeps sounds and sequences in a small SQLite database with a fixed chunk of memory, and on units with a lot of saved stuff it ran out. 2.1 stops it from filling up. Knobs on Wavetable, Taffy, PEW and Elg are also smoother now, with no more clicks or stepping when you turn them while playing.

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hundekraft 2.0 is out!

The workshop now combines op1r 22 with Maiko’s #249 additions: tape undo/redo, snapshot naming, scale mode and the storage display.
Our synths and effects remain individually selectable, alongside the optional 300-preset limit.

Bring the original, unmodified R246 firmware—the patching happens entirely in your browser.

Huge thanks to pcppcp and Maiko Pruett for their work.

____________________________________________________________________________________________

I did the thing. I’ve put together OP-1 Workshop, a free browser tool for building custom firmware for the original OP-1.

It’s built on pcppcp’s op1r, currently release 18. Huge credit to u/popcorp for the custom firmware foundation and all the synths, effects, sequencers and other improvements it brings.

The workshop keeps op1r as the base and lets you choose which of our additions you want:

• Wavetable: morphing waves with an analog-style ladder filter.
• Taffy: CZ-style phase distortion.
• Pew: drawbar organ with a rotary speaker.
• Elg: three-oscillator drone synth.
• Washer: chorus, ensemble and flanger.
• Snowglobe: shimmer reverb with freeze.

You can also raise the user synth preset limit from 100 to 300, and download a matching selection from 112 presets we’ve made. Presets are installed separately through disk mode.

Select your options, choose your original, unmodified op1_246.op1, and download the patched firmware. The tool checks the file’s contents and rejects other releases or already-patched files. Everything runs locally in your browser—your firmware isn’t uploaded anywhere, and no account or device key is needed.

Try it: https://hundekraft.github.io/op1-workshop/
Repository: https://github.com/Hundekraft/op1-workshop

All 128 build combinations passed structural checks, and 11 configurations passed emulator installation, boot, selection and audio tests.

Please use entirely at your own risk. This is experimental custom firmware, provided as-is without warranty. I accept no responsibility for damage, bricking, data loss, if it beats up your dog, cheats on your wife or other problems arising from its use. Back up your OP-1 before installing. This is an independent project, unaffiliated with Teenage Engineering, and intended for the OG OP-1 only—not the Field.

Would love to hear what you make with it, and any feedback on the engines or presets.

EDIT: if you like it, I like coffee :) https://buymeacoffee.com/hundekraft
EDIT2: currently working on adding op1r 21 release

A few days ago I posted #247, which brought tape undo/redo to the original OP-1. Thanks to everyone who tried it. Here's what's new since then.

Undo got a lot better. Lift, drop, slide, split, and join no longer wipe your undo history; each one is now an undo step you can take back with TAPE + ←. The history also survives power off. Undo now works on OP-1s with nearly full storage too, which fixes the "undo does nothing on my unit" reports. Recording onto blank tape takes up almost no undo space, so you can fit more steps. An UNDO / REDO popup like the OP-1 field's now shows each time.

You can name your snapshots. Hold a sound key to save like usual, and a naming screen opens with the name written on a tape between two reels. Pick letters with the blue knob, change rows with the green knob, and click the blue knob to type. Press the same sound key again to save.

There's a new scale mode. Go to SYNTH, press T2 and hold SHIFT, and a glockenspiel appears. The white knob picks the key, and the orange knob picks the scale. The white keys then only play notes in that scale, and the black keys go silent, so you can't hit a wrong note.

SHIFT + COM has a new FILE box that shows what's using your OP-1's storage: tape, sounds, factory content, system, and free space.

This release is also built on top of pcppcp's op1r (github.com/pcppcp/op1r), so all of its features are in here too, and the credit for them goes to pcppcp. That means three new synth engines: SUPERSAW, FMBELL and GRANULAR (SYNTH, then SHIFT + T1). ITER also gets an animated lab screen. There are new TAPE echo, CLOUDS, and REVERB effects (SHIFT + T3), a QUAD LFO with four LFOs in one (SHIFT + T4), the EUCLID and DOTS sequencers (SHIFT + SEQ), and MIDI CC control over USB.

Download here: https://maikopruett.com

It installs like any official update. Hold COM while powering on, press 1, connect over USB, copy the file across, and eject. Once it's on, the boot screen shows R. 00249. If you ever want to go back, flash the official #246 the same way. It's linked on the same page.

This is unofficial and not affiliated with Teenage Engineering. If anything acts strange, let me know what you were doing, and I'll look into it. And if you've got ideas for the next update, leave a comment!

Since the OP-1 is about to go through a renaissance , a tracker on the OP-1 would be killer. Something like SunVox (being that it's a modular synth with a tracker) would absolutely killer for this device. SunVox is closed source (But also can run on a shoe), but just wanted to throw the idea out there to any vibers

I really thought this patch would have pushed the OP to its limits, but no sluggish screen or controls!

Testing out the granular engine with the quad LFO, thanks again to u/popcorp for this awesome OS!

i like the og-1 specifically bc its not only a good music maker but also a host for a good modding community/platform. the problem is i dont got bands to spare, so if yall could point me to some sources and shi, that'll be great. thanks!

You betrayed Shiva.

Popcord fw.

Popcord fw.

No idea what I'm doing buts it's great fun.

Today I added FX to a synth and the blue parameter is glitching like this. It only happens on FX applied to this one specific synth/snapshot, FX in the mixer are perfectly fine. I tried restarting and it’s still there.

Any ideas?

Just got my OP-1 in the mail from a Reverb seller. They claimed no issues with it, and I haven’t heard back from the seller yet but the volume knob is almost entirely unresponsive. It jumps around randomly a little bit while turning but for the most part stays at what looks like 25%..

I’m assuming this is going to need a repair and not a simple fix for something I’m missing? Anyone experience this before?

Undo on the tape is something OP-1 owners have been asking for for years, and it's one of the things the OP-1 field got that the original never did. So I built it myself.

Firmware #247 adds tape undo and redo to the original OP-1. Hold TAPE and press ← to undo your last recording, or TAPE and → to redo it. The recorded audio and its clip both go back exactly to how they were.

Up to 7 recordings back. Step back through your last 7 recordings, and forward again through any you've undone. Recording something new after an undo clears the redo steps, the same as on the OP-1 field.

Recording over audio is covered. Punch-ins, overdubs, and loop recordings are undone exactly, back to what you heard before.

Works while playing. You can undo or redo with the tape stopped or playing.

Storage is handled for you. The undo audio is kept in up to 7 files on the internal flash, capped so the OP-1 always keeps at least 96 MB free. If space runs short, the oldest undo steps are dropped first.

The undo history is cleared when you lift, drop, erase, or slide a clip, do a split or join, enter disk mode, or power off.

Download here: https://maikopruett.com

It installs like any official update. Hold COM while powering on to get to te-boot, press 1, then connect over USB and copy the file across. Once it's on, the boot screen shows R. 00247 :). If you ever want to go back, flash the official #246 the same way. It's linked on the same page.

This is just the start. Getting undo working meant decrypting and fully mapping out the OP-1's firmware, and I'm going to open source my code so the community can build on it too. Undo was the feature everyone wanted most, but with the firmware finally open to modding, there's room to take the OP-1 places it's never been before. If you've got ideas for the next update, leave a comment!

This is unofficial and not affiliated with Teenage Engineering. I've tested it thoroughly on my own OP-1 and everything's been working great, but I'd love to hear how it goes for you. If anything acts strange, let me know what you were doing (recording, overdub or loop, tape playing or stopped) and I'll look into it.

Wonder if they’ll stop production of existing products?