Les

FM-1 firmware · 1.4.0

J6

A six-voice polysynth after the Roland JUNO-60, with its chorus, an arpeggiator and 16-step recorder, 56 factory sounds and a browser editor.

Made by
JackieAlacrity2373
Released
October 29, 2026
Install
On the FM-1 Firmware Hub · source on GitHub
Scan
Scanned, nothing harmful found · Oct 31 What we checked
Last checked
October 31, 2026

What J6 does

  • J6 turns the FM-1 into a six-voice polysynth after the JUNO-60, playable from the 27-key touch keyboard.
  • Each voice has one oscillator mixing saw, pulse, sub square and noise through a resonant low-pass filter that self-oscillates.
  • A shared ADSR, an LFO with delay and a stereo chorus with four settings shape the sound.
  • Play in Poly, Unison with spread or Solo, with portamento, hold and an arpeggiator running up, down or up-down over one to three octaves.
  • Record up to 16 steps with rests using REC, then loop them with SEQ at the tempo set on the GLO page.
  • Four knobs edit whatever the current page shows, and pressing a page button again flips to its second half.
  • Over USB it takes notes, velocity, pitch bend, pressure, sustain and program change, and LINK lets one FM-1 drive another.

Its modes

SOUND
The HOME page shows the sound name, play mode, arp, hold and sequencer state plus the 16-step pattern strip.
DCO
Mix the saw, pulse, sub and noise sources, and set range, pulse width and PWM source.
VCF
Set cutoff, resonance, envelope amount and key follow, with high-pass, envelope polarity, VCA mode and level on the second half.
ENVELOPE
Shape attack, decay, sustain and release for the filter and the volume together.
LFO
Set the wobble rate and delay and send it to pitch and to cutoff.
CHORUS
Choose the chorus setting, the play mode, portamento glide and unison spread.
GLOBAL
Set tuning, velocity, arpeggiator direction and octaves, plus tempo, screen theme and LINK.

What Les checked

J6 v1.4.0Scanned 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

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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