FM-1 firmware · v0.4.0-rc1
bongo-cat-studio
A little band of four cats: you play and loop the melody while keys, bass and drum cats follow your chords.
- Made by
- Impossible Knot
- Released
- October 23, 2026
- Install
- On GitHub
- Scan
- Scanned, nothing harmful found · Oct 31 What we checked
- Last checked
- October 31, 2026
What bongo-cat-studio does
- Four parts, your cat plus keys, bass and drums, can each use any of thirteen synthesis engines.
- Engines cover analog, phase, lo-fi, samples, voice, trio, wheel, granular, physical modelling, drums, noise, FM6 and slice.
- Press REC while stopped for a one-bar visual lead-in, then record a 1, 2 or 4 bar phrase.
- OVERDUB adds notes at the next phrase start, REPLACE clears the old take, and LFO undoes one step.
- The panel keyboard plays the selected cat, with key assist snapping notes into your chosen major or minor key.
- Harmony keeps the band in key with HOLD, COZY, DREAM and JAZZ progressions, one chord per bar.
- LIVE gives each cat a PLAY, MUTE and SOLO knob, with ENV as tap tempo that yields to external MIDI clock.
- SAVE and the CRC-checked autosave keep the phrase, sounds, mixer, harmony, tempo, coat, hat and room for next boot.
Its modes
- Studio
- Set tempo, swing, band energy and room reverb while the band plays.
- Harmony
- Choose the key, major or minor, the chord progression and key assist.
- Looper
- Set phrase length of 1, 2 or 4 bars, replace or overdub, timing feel and the metronome.
- Mixer
- Balance the levels of your cat, keys, bass and drums.
- Dress up
- Pick the coat, hat, room colour and calm or lively animation.
- Help
- Switch the metronome between off, record and on with knob 1.
- Sounds
- Choose the part, its engine, its factory preset and its level.
- Tone / Colour
- Adjust the eight engine controls, whose labels follow the chosen sound.
- Envelope
- Shape the selected part's attack, decay, sustain and release.
- Effects
- Set drive, chorus, delay and reverb for the selected part.
What Les checked
bongo-cat-studio v0.4.0-rc1Scanned October 31, 2026
What we checked for
- The file is exactly the one its author published
- It's the same file we saw when this release first came out
- It opens cleanly as an FM-1 firmware, nothing damaged
- It doesn't show up on your computer as a keyboard, mouse or other input device
- It doesn't show up as a USB drive or network adapter
- Its text mentions no computer command tools, like PowerShell, Terminal or a download command
What we found
- MIDI and audio, as expected
- A serial port, which many FM-1 firmwares keep for debugging. It can't type into your computer.
StatusScanned, nothing harmful found
Les scans every firmware here whose file is public, and shows what it checked and what it found. A scan lowers the risk; it can't rule it out. This firmware is made by its author, not by Les or M-VAVE. Back up first, and install at your own risk. How Les scans firmware
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Les is independent and not affiliated with M-VAVE or the firmware authors. M-VAVE and FM-1 are trademarks of their owners.