10-06-2026, 12:36 AM
(This post was last modified: 10-13-2026, 09:58 PM by bandersong.
Edit Reason: update
)
Demo video up! o7
Hello Everyone
Please read everything carefully.
https://chopshop-synth.pages.dev/
This is the direct link to the tool. It walks you through making the firmware. You ultimately flash with Elektron Transfer (for now).
_____________________________________________________________________________________________________
Chopshop is one web page that builds modded firmware for two Elektron instruments from your own OS file. You drop Elektron's .syx (or the _dist.zip), the page identifies it by checksum, you pick mods, and it rebuilds the firmware in your browser with Elektron's open-source firmware tool compiled to WebAssembly. The download unlocks only if the output's sha256 equals the published hash. Nothing is uploaded, no Elektron files are shipped, and it works offline once loaded. You flash with Elektron Transfer.
### Analog Rytm MK1 and MKII (OS 1.73)
- **CHOP / Sample Focus.** A CHOP page where the 12 pads play one track's sample from 12 start markers, with hi-res markers, DIV, LAY, RND and step-lock in GRID REC. On the MK1 it lives on SAMPLE (press SAMPLE, pause, SAMPLE again). On the MKII it is the third SAMPLE page (SAMPLE, SMPL WAVEFORM, CHOP) and also has END.
- **SMP CUT** (needs CHOP). A second FILTER page (press FILTER, pause, FILTER again) with a low cut and a high cut per track.
- **Classic CHOP + step-lock** (MK1 only, older build): the earlier 3-knob CHOP page with step-lock, euclid accents and velocity humanise. No Sample Focus, no SMP CUT.
### Analog Keys (OS 1.56)
- **Chord memory.** Hold 2-4 keys + FUNCTION + OCTAVE UP to capture a chord; every key then plays it with itself as the root. FUNCTION + OCTAVE UP with nothing held turns it off.
- **JOY RANDOM.** FUNCTION + OCTAVE DOWN gives the active track new random joystick assignments. [NO/RELOAD] + [SOUND] undoes it.
- The two are independent: take either, or both.
Every device also has a **Control build** (Elektron's own code, only repacked): flash it first, and if it boots and plays normally the route works on your unit.
### What's tested
I ran MK1 Sample Focus + SMP CUT and Keys chord + JOY RANDOM through a 20-minute live jam with two other people. MIDI sync was solid, and I hit JOY RANDOM many times without a hang.
**MKII (new, 2026-10-13):** the CHOP + SMP CUT build and the Control build have now run on a real MKII. The Control build was accepted and boots. On the CHOP + SMP CUT build, LCT and HCT start at OFF, and the CHOP page, first-hit fix, LAY and SMP CUT all passed a short 4-step test card. Not tested yet on the MKII: saving a project and power-cycling, fast rolls, live REC, and the CHOP-only build on its own. The MKII builds don't have the MK1's newer live-REC lock fix yet, and they still have END mode. (Those results are from one MKII, from my own hands-on test.)
One thing you may see: with 16 steps filled and Start automated, step keys 1 and 9 flash in the record menu. It does the same on the Control build, so it's the unit's own display, not the mod.
Going back to stock over a mod build hasn't been tried on a unit. The mods never touch the recovery code.
### Read before you flash
These are for OS 1.73 (Keys 1.56). Elektron's support pages now serve only 1.74 for the Rytm, and a unit on 1.74 can't take these files; going back on an MKII is likely not possible (unverified, ask Elektron support first). A 1.74 port is a planned follow-up, no date. The Analog Four isn't supported yet.
### Analog Four owners wanted
I'm looking for owners of the **Analog Four MK1 and MK2** for future testing and porting. If you have one and are up for trying builds (carefully, with a backup and a recovery plan), reply here or open an issue at https://github.com/bandersong/chopshop/issues .
Unofficial: not made, checked or endorsed by Elektron; flashing is at your own risk.
Page: https://chopshop-synth.pages.dev/ · Source (GPL-3.0-or-later): https://github.com/bandersong/chopshop · Mods repo: https://github.com/bandersong/analog-rytm-chop
Roadmap:
Analog Rytm MKII: first hardware test done (2026-10-13); the live-REC fix and the longer test rows are next
Analog Four Mk1 and Mk2 port (Blocked; need testers)
If anyone has any ideas for possible mods please post
I'd like to thank and credit the following projects:
gdeo607/rytm1_mods: the MK1 mod framework, symbol map and build/verify tooling that CHOP is built on.
mischa85/elektron-firmware-tool (MIT): Elektron OS container tool.
irpina/elekloader: mod loader.
Hello Everyone
Please read everything carefully.
https://chopshop-synth.pages.dev/
This is the direct link to the tool. It walks you through making the firmware. You ultimately flash with Elektron Transfer (for now).
_____________________________________________________________________________________________________
Chopshop is one web page that builds modded firmware for two Elektron instruments from your own OS file. You drop Elektron's .syx (or the _dist.zip), the page identifies it by checksum, you pick mods, and it rebuilds the firmware in your browser with Elektron's open-source firmware tool compiled to WebAssembly. The download unlocks only if the output's sha256 equals the published hash. Nothing is uploaded, no Elektron files are shipped, and it works offline once loaded. You flash with Elektron Transfer.
### Analog Rytm MK1 and MKII (OS 1.73)
- **CHOP / Sample Focus.** A CHOP page where the 12 pads play one track's sample from 12 start markers, with hi-res markers, DIV, LAY, RND and step-lock in GRID REC. On the MK1 it lives on SAMPLE (press SAMPLE, pause, SAMPLE again). On the MKII it is the third SAMPLE page (SAMPLE, SMPL WAVEFORM, CHOP) and also has END.
- **SMP CUT** (needs CHOP). A second FILTER page (press FILTER, pause, FILTER again) with a low cut and a high cut per track.
- **Classic CHOP + step-lock** (MK1 only, older build): the earlier 3-knob CHOP page with step-lock, euclid accents and velocity humanise. No Sample Focus, no SMP CUT.
### Analog Keys (OS 1.56)
- **Chord memory.** Hold 2-4 keys + FUNCTION + OCTAVE UP to capture a chord; every key then plays it with itself as the root. FUNCTION + OCTAVE UP with nothing held turns it off.
- **JOY RANDOM.** FUNCTION + OCTAVE DOWN gives the active track new random joystick assignments. [NO/RELOAD] + [SOUND] undoes it.
- The two are independent: take either, or both.
Every device also has a **Control build** (Elektron's own code, only repacked): flash it first, and if it boots and plays normally the route works on your unit.
### What's tested
I ran MK1 Sample Focus + SMP CUT and Keys chord + JOY RANDOM through a 20-minute live jam with two other people. MIDI sync was solid, and I hit JOY RANDOM many times without a hang.
**MKII (new, 2026-10-13):** the CHOP + SMP CUT build and the Control build have now run on a real MKII. The Control build was accepted and boots. On the CHOP + SMP CUT build, LCT and HCT start at OFF, and the CHOP page, first-hit fix, LAY and SMP CUT all passed a short 4-step test card. Not tested yet on the MKII: saving a project and power-cycling, fast rolls, live REC, and the CHOP-only build on its own. The MKII builds don't have the MK1's newer live-REC lock fix yet, and they still have END mode. (Those results are from one MKII, from my own hands-on test.)
One thing you may see: with 16 steps filled and Start automated, step keys 1 and 9 flash in the record menu. It does the same on the Control build, so it's the unit's own display, not the mod.
Going back to stock over a mod build hasn't been tried on a unit. The mods never touch the recovery code.
### Read before you flash
These are for OS 1.73 (Keys 1.56). Elektron's support pages now serve only 1.74 for the Rytm, and a unit on 1.74 can't take these files; going back on an MKII is likely not possible (unverified, ask Elektron support first). A 1.74 port is a planned follow-up, no date. The Analog Four isn't supported yet.
### Analog Four owners wanted
I'm looking for owners of the **Analog Four MK1 and MK2** for future testing and porting. If you have one and are up for trying builds (carefully, with a backup and a recovery plan), reply here or open an issue at https://github.com/bandersong/chopshop/issues .
Unofficial: not made, checked or endorsed by Elektron; flashing is at your own risk.
Page: https://chopshop-synth.pages.dev/ · Source (GPL-3.0-or-later): https://github.com/bandersong/chopshop · Mods repo: https://github.com/bandersong/analog-rytm-chop
Roadmap:
Analog Rytm MKII: first hardware test done (2026-10-13); the live-REC fix and the longer test rows are next
Analog Four Mk1 and Mk2 port (Blocked; need testers)
If anyone has any ideas for possible mods please post
I'd like to thank and credit the following projects:
gdeo607/rytm1_mods: the MK1 mod framework, symbol map and build/verify tooling that CHOP is built on.
mischa85/elektron-firmware-tool (MIT): Elektron OS container tool.
irpina/elekloader: mod loader.
Browser firmware builder for Elektron Analog Rytm MK1/MKII and Analog Keys mods. Unofficial. Your own OS file never leaves your computer.
DEPRECATED: use CHOPSHOP instead (github.com/bandersong/chopshop). Sample CHOP mode for the Elektron Analog Rytm MK1.