Les

FM-1 firmware · v0.1.2

CRT-4

A four-track groovebox that plays the sound chips of nine game consoles and home computers, with drums plus three tracks of each machine's sounds.

Made by
devrvega
Released
October 16, 2026
Install
On GitHub
Scan
Scanned, nothing harmful found · Oct 31 What we checked
Last checked
October 31, 2026

What CRT-4 does

  • You play nine consoles, from the Atari 2600 and C64 to the SNES, PlayStation and N64, each with its own sounds.
  • Every console gives you two drum kits and sixteen sounds: four basses, four keys, four leads and four of its own.
  • Track 1 holds the drums and tracks 2, 3 and 4 play the console's sounds with its echo or reverb.
  • You write sixteen-step patterns live with REC, step by step, or by pressing the white keys as steps.
  • Patterns chain up to 64 long, and sixteen chords chain alongside them, one each time a pattern starts.
  • Hold FX and a white key for repeats, stutter, reverse, fills, solos, fades and more, written in as you play.
  • Each console keeps its own song, saved by itself a few seconds after you stop, or at once with SAVE.

Its modes

Patterns
Pick the next of sixteen patterns, build a chain, and set tempo, swing, length and key.
Steps
Turn the white keys into a track's 16 steps to write and edit notes, lengths and locks.
Sound
Set the four knobs of the track's sound, or the drum part's tune, decay, tone and level.
Track
Set the track's level, pan, echo or reverb send, and glide.
Chords
Choose from sixteen chords, chain them, and set a track to follow them.
Mixer
Set the four tracks' levels, mute them, or pick one.
FX
Hold white keys for punch-in effects and set the console's echo or reverb.
Setup
Set tune, MIDI out and clock, and bring back the console's demo song.

What Les checked

CRT-4 v0.1.2Scanned 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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