About
- 6-channel USB audio: Each track gets its own USB channel: six separate stems in your DAW.Based on the work of scottmetoyer
- Latching mute: TRACK + FUNC locks the mute mode: no more holding FUNC.By drumkilla
- Trig preview: Sequencer stopped, hold a step and press PAGE to hear it.By drumkilla
- Scrolling names: Sound names too long for the screen scroll in the browser.By drumkilla
- Syntakt engines: SD VINTAGE, CP VINTAGE, SY TOY, SY BITS and SY SWARM as extra machines, read from your Syntakt OS file.
- Samples OS: The Model:Cycles starts as a Model:Samples and plays your own samples.
README
Modded-Cycles
Firmware mods for the Elektron Model:Cycles. The first goal: send the 6 tracks over USB as 6 separate channels instead of the stereo mix only, so you can record real stems in your DAW. Then go further: new machines, more channels, more features.
⚠️ No Elektron firmware is included in this repository — neither original nor modified. You bring your own copy of the official OS, downloaded from elektron.se. This repository only contains analysis, byte-level patch tables, assembly/C sources and tools. Not affiliated with or endorsed by Elektron. Flashing a modified OS is at your own risk and may void your warranty.
Quick start: flash from your browser
Open the web flasher in Chrome, Edge or Opera (desktop). What each mod does, step by step: the guide. Tick the mods you want, drop your official OS file, connect the Model:Cycles over USB and flash. The page builds the modified firmware from your file and sends it over Web MIDI. Everything happens in your browser: nothing is uploaded anywhere.
You need:
- your official
model-cycles_OS1.13.syx(elektron.se, unzip the download); - a USB cable. On the Model:Cycles, open
CONFIG > UPGRADEand confirm: it waits for the firmware.
The web flasher only sends over USB, and only offers mods that keep OS updates over USB working.
Its Samples OS tab turns the Model:Cycles into a Model:Samples (drop both official OS files); coming back needs a MIDI interface.
The SD VINTAGE box adds the real Syntakt SD VINTAGE engine as a 7th machine SDVtg next to SNARE (default), or puts it in place of SNARE; both tested on a real Model:Cycles: drop your official Syntakt_OS1.42.syx (elektron.se; 1.41 works too, same engines) as well, the engine is read from it in your browser.
If a Model:Cycles ever stops starting, recovery goes through the startup menu (FUNC + power on, then TRIG 4),
which only listens to the MIDI IN: that needs a MIDI interface and the command-line scripts below (FLASH.md).
Command line
A pure-Python toolchain: no compiler, no firmware in the repo. See BUILD.md (in French).
python3 tools/build.py --list python3 tools/build.py -i model-cycles_OS1.13.syx -t 6ch-usbup # 6 channels, keeps OS updates over USB python3 tools/build.py -i model-cycles_OS1.13.syx -t 6ch-multiout # 6 channels, reference build (no USB updates) python3 tools/build.py -i model-cycles_OS1.13.syx -t sdvintage-snare # SD VINTAGE machine instead of SNARE python3 tools/build.py -i model-cycles_OS1.13.syx -t 6ch-usbup,latching-mute,trig-preview,browser-scroll
Then flash with the ready-made scripts. They install the dependencies, check the file, guide you and send it — see FLASH.md (in French).
./flash.sh # macOS / Linux flash.bat # Windows (double-click)
The web flasher is a JavaScript port of build.py and mtlib, checked byte for byte against the Python
(tools/webflash_check.sh, tools/webbuild_check.sh, tools/webflash_smoke.sh).
Features
By priority. Feasibility is detailed in note 10 (in French).
| Feature | Status |
|---|---|
| 6-channel USB output | ✅ tested on a real Model:Cycles — in the web flasher |
| Keep OS updates over USB with the 6-channel mod | ✅ 6ch-usbup, the version the web flasher installs (note 13) |
| Steady USB stream (a Reddit report: glitches with 6-channel audio and Model-TG, worse when muting tracks) | ✅ found in the stock OS's USB driver: each block went to the computer right after being computed, so at a moment that moved with the processor load, and the 6-channel mod's buffer only tolerated 0.2 ms of it; Model-TG and the Syntakt engines make the load swing (idle and muted tracks, effects off). Now each block leaves at the start of the next one, at a fixed moment (0.67 ms more latency), the queue is lined up when the stream starts, the 6-channel buffer gains a slot, and with Model-TG a muted track's stem is no longer cut off. A simulator running the OS's own USB driver goes from thousands of damaged frames to none (note 35, in French); tested on the hardware |
| The real Syntakt SD VINTAGE engine, extracted at build time from your Syntakt OS file | ✅ sdvintage-exact: the Syntakt's own code and tables, relocated into the Model:Cycles, replace SNARE — sample-identical to the Syntakt in emulation, and the bootstrap's own decompressor reads the bigger OS back exactly; tested on a real Model:Cycles (2026-09-30, flashed over USB from the web flasher); now command line only (build.py --syntakt): the web flasher only adds engines (note 17) |
| The real SD VINTAGE as a 7th machine (SDVtg), next to SNARE | ✅ sdvintage-7th: 7 machines in the MACHINES menu, its own knob names and defaults from the Syntakt (Inharm, Freq Complex, Pitch Sweep, Mod Envelope), SNARE unchanged; tested on a real Model:Cycles (2026-09-30, web flasher); 26 checks on the OS's own code in emulation (note 18) |
| The real CP VINTAGE clap as an 8th machine (CPVtg), with SDVtg | ✅ syntakt-vintage: 8 machines in the MACHINES menu, CPVtg with the Syntakt's knob names and defaults (Body Char, Balance, Spacing Crunch, Body Envelope); sample-identical to the Syntakt in emulation (26 checks); tested on a real Model:Cycles (2026-09-30, web flasher) (note 19) |
| Pick the Syntakt engines you want (SD VINTAGE, CP VINTAGE, SY TOY, SY BITS, SY SWARM) | ✅ one checkbox per engine in the web flasher, any combination, added after the 6 original machines; SYToy (SY TOY: Form, Impact, Bright, Partial Decay) is sample-identical to the Syntakt in emulation and tested on a real Model:Cycles, alone and with SDVtg + CPVtg (2026-09-30); SYBit (SY BITS: Detune, Balance, Rate Redux, Waveform, PUNCH = Bit Redux) is sample-identical in emulation and tested on a real Model:Cycles on its own (note 21); the new SYSwm (SY SWARM supersaw: Noise Mod, Detune Anim, Detune, Osc Mix, PUNCH = sub-octave) is sample-identical in emulation and not hardware-tested yet (note 22). Set tracks that use an added machine back to an original machine before changing the choice or going back to the official firmware (note 20) |
| Extra drum engine: SD VINTAGE (vintage snare from the Syntakt) | ✅ step 1 (replaces SNARE) tested on a real Model:Cycles; v2 retuned on the real Syntakt SD VINTAGE running in our emulator (same pitch, sweep, decay and noise spectrum, knobs mean what they mean on the Syntakt) — command line only for now (note 16) |
| 12-channel USB output (per-track pan) | 🟡 feasible, to develop (through an 8-channel milestone: 6 tracks + stereo mix, note 11) |
| Change the effect algorithms | 🔴 no (tweaking parameters: 🟡) |
| Sample engine (like the Model:Samples) | ✅ through Model-TG by TinyGregAudio (MIT): a Sampler machine with seven playback modes, resampling, a retrig page with master FX, slide trigs and more. Offered in the web flasher at its version 1.1, built by its own build with two changes from this project: in mute mode, each track key mutes at once, as with the latching mute alone (Model-TG queues them until you leave the mode); with 6-channel audio, a muted track's stem rings out instead of being cut off (note 35); plus this project's steady USB stream; on its own or with the 6-channel mod. With the Syntakt engines: a combined version (the Sampler stays the 7th machine, the engines follow), where slide trigs work on the engines too. Model-TG 1.1 with the 5 engines and 6-channel audio is tested on the hardware (note 31, in French) |
| 2 LFOs, syncable and assignable | 🟠 heavy (more destinations for the current LFO: 🟡) |
| Polyrhythm (per-track time signature) | 🟡 partly there in stock firmware |
| MIDI control over USB (clock, start/stop) | ✅ already supported in stock firmware (settings only) |
| Arpeggiator (in place of the retrig) | ✅ in the web flasher: hold several notes with RETRIG (or A.On) and they play as an arpeggio at the retrig rate; FUNC + RETRIG gains Arp (UP, DOWN, UPDN, RAND, PLAY, OFF) and Oct (1 to 4), saved with the pattern. In live recording, the notes it plays are recorded one by one (version 1.14, tested on the hardware). Checked in the emulator against the OS's own event loop, and tested on the hardware with Model-TG, the 5 engines and 6-channel audio (note 32, in French) |
| Easier trig removal (a stock OS flaw) | ✅ in the web flasher: on the stock OS, a press on a trig longer than 0.2 s counts as a hold and the trig stays, so the soft keys often need a second press; with this mod, letting go within half a second removes it (empty steps, knob turns while holding: unchanged). Checked in the emulator on the OS's own code, from the key scan to the sequencer, and tested on the hardware with Model-TG, the 5 engines, 6-channel audio and the arpeggiator (note 33, in French) |
| Scale (chromatic mode) | 🟡 feasible, medium effort |
| Polyphony for the synth engine | 🔴 very hard |
Also in the web flasher, by drumkilla (tested on real hardware by their author, our build matches their own tool byte for byte):
| Tweak | What it does |
|---|---|
latching-mute |
Hold TRK and tap FUNC: mute mode stays on, so you mute tracks without holding FUNC |
trig-preview |
Sequencer stopped or paused: hold a step and press PAGE to hear it (note, length, p-locks) |
browser-scroll |
Long names scroll in the sound browser |
Requests from the community (Reddit) and how we handle them: note 15 (in French).
| Request | Status |
|---|---|
Mute without holding FUNC |
✅ latching-mute (above) |
| Bundle with trig preview | ✅ trig-preview (above) |
| Run the Model:Samples OS on a Model:Cycles | ✅ tested on a real Model:Cycles (2026-09-29) — Samples OS tab of the web flasher, or tools/crossflash.py. Built from both official files: same bootstrap, same updater, same RAM setup on both machines. The way back to the Cycles OS goes through the MIDI IN (note 15 §3) |
| Port the Syntakt digital machines | 🟡 the Syntakt's audio engine (a second ColdFire) runs in our emulator; its FM machines turn out to be the Model:Cycles machines plus SD VINTAGE and CP VINTAGE. SD VINTAGE v2 is retuned on it (note 16) |
Project status
- The 6-tracks-over-USB mod exists (scottmetoyer/ms-multi-output, MIT) and is ported here as a tweak. Our build reproduces the known-good MAIN OS byte for byte. It now works on a real Model:Cycles (before, it had only run on a Model:Samples running the Cycles OS).
- The official OS 1.13 (latest version) has been analysed in depth (note 09).
- The synth engine (the 6 machines are 6 mappings of one FM engine) is decoded and emulated (
tools/emu/). One more engine, SD VINTAGE, is written in C, compiled for the ColdFire CPU and validated in the emulated engine (note 14). - Milestone 1 reached (2026-09-29): the 6-channel mod and SD VINTAGE work on a real Model:Cycles.
Roadmap: notes/08-feuille-de-route.md (in French).
Documentation
The technical documentation is written in French.
| Document | Topic |
|---|---|
BUILD.md |
Building a modified firmware image (pure Python) |
FLASH.md |
Flashing your Model:Cycles: detailed guide and scripts |
dossier-technique.md |
Summary of the Elektronauts thread "Model:Cycles Q&A with Ess", every fact quoted from its source |
notes/README.md |
Index of the technical notes and key figures |
notes/10-faisabilite-fonctionnalites.md |
Feasibility, feature by feature |
notes/21-architecture-materielle.md |
Hardware architecture, read from photos of the PCB: CPU, memories, USB PHY, audio output, MIDI input, key and LED latches |
tools/ · tweaks/ · docs/flasher/ |
Build tools (mtlib), patch tables (JSON), web flasher |
Credits
Upstream projects, all MIT licensed, none including firmware:
scottmetoyer/ms-multi-output— the 6-channel mod (Model:Samples and Model:Cycles)drumkilla/elektron-model-tweaks— the latching-mute, trig-preview and browser-scroll tweaks (intweaks/, unchanged except a 3-byte fix to trig-preview so it also works while paused, note 34),mtlib(SysEx transport, aPLib, ELE3 container and HMAC in Python) and the JSON tweak format, vendored intools/mtlib/TinyGregAudio/Model-TG— the Sampler machine, resampling, retrig and master FX, slide trigs, and more; generated from a pinned commit (v1.1.0) bytools/gen_model_tg.pywith its own build, from a copy of its source with three listed changes (mutes at once, the same trig-preview fix, stems of muted tracks;tweaks/model-cycles_OS1.13/30-model-tg.json, license inLICENSE-Model-TG);30-model-tg-st.json, the base of the combined version, is built the same way with one more listed changemischa85/elektron-firmware-tool— unpacking, repacking and re-signing.syxfiles (alternative C toolchain)mxldyn/octamax— reverse engineering of the Octatrack OS (method, tools, pitfalls)
Pictures in the README load from GitHub.
- Language
- Python
- Stars
- 41
- Forks
- 4
- Created
- 09-24-2026
- Last commit
- 3 hours ago
Added by 18nelli on Today · Last edited by 18nelli, 2 hours ago · History (2 versions)