ORBIT

Make a beat, shape three synths, then rearrange their events on Tape.

ORBIT is a four-track groovebox firmware for the M-VAVE FM-1: three synth parts and a drum machine, played through a color-coded Synth / Drum / Event Tape / Mixer workflow. Record a loop, turn it into a song, and keep your favorite sound controls together with user macros. Based on SLOOP/Felucca, with original ORBIT engines and graphics inspired by the original OP-1's four encoder roles.

Install · Get started · User guide · MIDI controllers · 0.7.0 release notes · Try the native preview

Event Tape, synth, envelope, mixer and sampler screens

Actual firmware UI rendered by the native host harness. These are earlier ORBIT screens, not hardware photographs or new 0.7.0 captures.

Make a loop, then move its events

Select track 4 with ALGORITHM and choose a drum kit with PRESETS. Press REC and play; on an empty project in free mode, press REC on the next downbeat to close the loop.
Select track 1, choose a sound, and record a bass line. Add chords or a melody on tracks 2 and 3.
Press HOME for Event Tape. Set the region with KNOB 2/3, choose COPY or LIFT with KNOB 4, and press OCT- to capture it. Set the destination with KNOB 1 and press OCT+ to drop it.
Press GLO for Mixer to balance the four tracks. Save variations into sections A-D and play or chain them with the SAVE layer.

Tape edits sequencer events, including notes, drum hits, timing, fills and parameter locks. It is not audio recording, PCM overdubbing or tape-speed playback. Drop overwrites destination events, so save a section before experimenting. See the Tape controls.

What makes ORBIT its own instrument

Event Tape: a four-track event timeline with reels, an inclusive selection and COPY / LIFT / DROP, alongside the step sequencer.
Original sounds: SWARM's six detuned harmonic oscillators, PULSE's dual pulse/PWM synthesis, FM4's four sine operators, and CLOUD, an oscillator-source granular engine. CLOUD makes grains from oscillators; GRAIN makes grains from samples.
Controls that follow the sound: four blue / green / white / orange encoders, faster travel through wide ENV/LFO ranges, and an instant preset list that auditions each selection on Tape or Mixer.
User macros: assign four destinations on MACROS, edit their values on PERFORM through EDIT/SELECT, and save the map with a USER sound or project. HOME remains Tape / Visualizer.
A real-firmware preview: the native preview runs ORBIT's C sound engine, sequencer and display rather than a separate browser synth.

Sounds and performance

Area	What you can play and edit
Instruments	17 engines, 189 factory sounds in the default build: analog, FM, phase distortion, chip, sampler, formant, three-oscillator, organ, sample granular, SWARM, PULSE, FM4, FM6, PHYS, NOISE, CLUSTER and CLOUD
Tracks	3 synth + 1 drum multitimbrality; synth parts share 8 voices globally, not eight each. Engine limits and CPU load also apply: CLUSTER at most 4 per part, CLOUD at most 3
Sound design	ADSR and envelope destinations, tempo-synced envelopes and LFO, retrigger/free-running and bipolar/unipolar LFO, glide, voice modes and ANALOG LP/BP/HP filter
Sequencing	Up to 64 steps per track, four-note chords, ties, ratchets, swing, note length, step velocity, 24 parameter locks per track, microtiming and fill conditions
Live playing	Free or tempo recording, overdub, note repeat, one-key chords, mute/solo/fill, section chains, MIDI keyboard step entry and live drum mutes
Effects	Per-track INSERT with eight effect types and dry/wet; filter, slicer and sends; 27 punch-in effects, REV/ECHO THROW and dotted delay; master DUST/DUCK/filter and a look-ahead limiter
Texture	A separate background bed: vinyl, tape, rain, wind, radio, room tone or USR sample, with tone, tempo movement and optional ducking
Your material	Four user sample slots, sample CHOP and drum-kit editing, SYN1-SYN4 drum synthesis, 32 USER sounds, four project/section slots and a 27-patch FM6 bank
Connections	USB MIDI, TRS MIDI IN, MIDI clock, sustain, pitch bend, Program Change and 16 persistent MIDI-learn slots; stereo USB audio at 44.1 or 48 kHz
Editor	Sound and macro editing, piano roll, MIDI files, song arrangement, DX7 SysEx, samples, libraries and full backup/restore over Web MIDI

CLUSTER uses a translated original OP-1 #246 oscillator core with 16 raw presets; pitch, envelope, velocity and effects are ORBIT's. Its four-voice cap is conditional on the shared budget and available CPU time, not a hardware polyphony guarantee. Read CLUSTER's scope and limits.

Listen and explore

Listen to FIRST LIGHT: an original four-bar, 108 BPM loop of FM4 bass, SWARM chords, PULSE melody and 808 drums, rendered by the C sequencer/DSP. Hear the original engine examples. These are host renders, not FM-1 recordings.

On the device, load FIRST LIGHT through hold HOME > SYSTEM > DEMO SONG > OCT+ > OCT+ again. Stop and save your work first: it replaces the working patterns and sounds. See the guide.

FIRST LIGHT on Event Tape

Install

The browser installation address is dspaudio.github.io/orbit. Check the version shown by the installer before writing.

The site downloads the latest stable release automatically and validates its package before enabling Connect. Use Chrome or Edge, a USB data cable and a direct connection. Connect grants Web MIDI SysEx access; Install is a separate action after device preflight. Keep power and USB connected during the write. If the download fails, retry it; the page does not accept a local package picker.

BACKUP before every update. Stop playback and use the editor's Projects / Backup export. ORBIT 0.7.0 writes ORP7 projects and OPB2 preset banks; it imports legacy ORBIT formats, but raw SLOOP 2.6 FUN6 is rejected. Older firmware cannot read new saves, and its autosave may overwrite them. Keep a pre-update backup for a downgrade. See storage and recovery.

Local fallback for a verified package:

python3 -m pip install mido python-rtmidi
python3 tools/fm1_install.py --info
python3 tools/fm1_install.py build/orbit.fwsc

The release target is 0.7.0, install identity FM-1_900. Build with the default command, not --release. See BUILDING.md for the toolchain, local site generation and CLI instructions. Generated firmware packages are not committed to this tree.

Validation: 0.7.0 was installed on an FM-1, with transfer completion, automatic reboot and actual version/PING responses verified. The earlier short USB recording of 0.6.0 on 2026-10-10 is historical, not 0.7.0 audio evidence. 0.7.0 hardware timing, power-loss recovery and physical crackle resolution have not been verified. Measurements and release gates belong in the validation record, not a product promise.

Try the native preview

Python 3, a C compiler and Pillow are required:

python -m pip install -r requirements.txt
python tools/orbit_preview.py --port 8080

Open http://127.0.0.1:8080 and press Start audio. The preview includes its own demo pattern; firmware boot does not load that preview pattern. Audio is buffered approximately 250-550 ms, project saves are nonpersistent host doubles, and sample upload is unsupported. Button taps work; held-button menus and layer combinations require the hardware. The separately deployed WebAssembly emulator is not automatically updated by this release.

Documentation

GUIDE.md: panel workflow, recording, Event Tape, sound design, macros and saving.
MIDI control: channels, CC learn, MiniLab routing and controller limits.
BUILDING.md: build, local installer site and checks.
0.7.0 release notes and validation record.
Earlier releases: 0.6.0, 0.5.0, 0.4.1; SLOOP 2.5 integration.
Original ORBIT engines, CLUSTER, design, editor protocol and Dots.

Origin, credits and licensing

ORBIT began from the isod89/sloop-fm1 v2.3 snapshot d691ba7b2d922f1a1f41a3622cffe29ce41c5506, not a fork retaining upstream history. SLOOP v2.4.1 and v2.5 changes were subsequently integrated; 0.7.0 brings the functional v2.6 changes from immutable commit d30d6553353373cf5506b9ed285fc4a2aa0c30ef while retaining ORBIT's registry, graphics and storage contract. The original README remains available.

Thanks to SLOOP's authors and community, and Felucca by Leo Kuroshita (@kurogedelic) / Hügelton Instruments for the synthesis, sequencing, editor and update foundations. Copyright (C) 2026 Leo Kuroshita (@kurogedelic), Hügelton Instruments; original notices are retained. Other credits include ChanceTheMaker and keremimo (MIDI input/clock), @renebohne (note lights/Program Change), Versilian Studios and Sonic Pi (CC0 samples), Terminus (SIL OFL), Fukiai (MIT), msfa/Dexed (FM6, Apache-2.0), DaisySP/Rings (PHYS) and the credited PHASE/VOICE references.

Code is GPL-3.0-only, with the existing msfa exception and asset notices: LICENSE, LICENSING.md. Distribute corresponding source with firmware. Extracted OP-1 tables and factory data retain Teenage Engineering's original rights; they are not CC0 or newly GPL-licensed assets, and extraction alone does not establish distribution permission. See asset provenance and rights. ORBIT's graphics are original; no OP-1 logo or artwork is included. ORBIT is not affiliated with M-VAVE or teenage engineering. No warranty.