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The Firmware Hub · FM-1 · VESPER

VESPER for the M-VAVE FM-1

VESPER2.0.2

by Fat Cat Studios GitHub ↗

synthambient · drone

An ambient worship synth. Each scene layers four lush voices in any major key around a crystal orbit home screen: pads, plucks, piano and swells. Shape them with drive, tone, granular clouds, shimmer, reverb and delay, then play live over the scene or record into it.

Text by the maker.

Install VESPER on the hub .fwsc (597 KB)

About it

Engines
Analog / VASamplerPhysical modellingVoice & speech
Its own: LUSH: analog plucks/bass/supersaw · sampled piano/marimba/glock · modal handpan/kalimba, plucked guitar · formant VOX
Runs on
FM-1 · Browser ↗
Release
2.0.2 · released 9 Nov 2026 · on the hub since 30 Oct 2026597 KB · what's new
Licence
GPL-3.0 · source ↗ · copy on the hub
Flash chip
Every FM-1, the newer chip 0xB36014 too
Identity
FM-1_8837202what it reports over USB while it runs
Build
Built by its maker, not signed
Popular
↓ 167 installs via the hub · ★ 2 on GitHub

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Changelog

What changed, version by version5 versions

2.0.2 (2026-11-09)

  • Works fully on the newer FM-1s. Units sold since autumn 2026 have a different flash chip (a UC25HQ80 instead of the Puya P25Q80). On those units 2.0.1 played but could not save, and could not install another firmware over itself. 2.0.2 recognises both chips (fm1-base PR #35's check; nothing else of the base changed).
  • Identity FM-1_8837202.

2.0.1 (2026-10-31)

  • MIDI keyboards play again: a note from USB or the TRS jack sounds on the focused layer's voice. 2.0.0 left them silent.
  • Identity FM-1_8837201, the FM-1 Firmware Hub's pattern for VESPER.
  • The source follows fm1-base's usual layout (app/, base/).

2.0.0 (2026-10-30)

VESPER is rebuilt on fm1-base and felucca-bsp instead of M-VAVE's FM1 Open SDK. The scenes, sounds and screens are the same.

  • Samples built in. Piano, marimba and glockenspiel are part of the firmware. There is no separate sample install, and the Firmware Hub installs VESPER directly.
  • User presets:
  • Hold SEL and turn PRESETS to step through your saved presets.
  • A saved preset keeps its scene, sounds, FX and SPACE, even when it is renamed. In 1.x, renaming lost them.
  • Screen: the panel is tuned as 1.x tuned it. Update screens are in VESPER's colours.
  • Audio:
  • Lighter on the chip: the sample decoder and the voices' maths are rewritten, with identical sound.
  • Under heavy load, the oldest synth voices are released first instead of the sound breaking up.
  • Bluetooth MIDI is not in 2.0 yet.
  • Projects saved in 1.x do not carry over.

1.1.0 (2026-10-29)

  • Smoother screen, about 8 KB more free memory, SEQ with 5 pages, and VESPER's own identity FM-1_8837001.

1.0.0 (2026-10-29)

First release.

CHANGELOG.md on GitHub ↗