DUELL 1.0

MultiMorphing Bitimbral Synthesizer by OSCILL/R

Two synths in one small box. DUELL is free, open-source firmware (GPL-3.0) for the M-VAVE FM-1, a fork of Felucca: a bitimbral synthesizer with two independent parts, playable in three modes (DUEL, STEREO, LAYER), with a morph that glides between two versions of every sound. This release is the device package, the web installer and the web editor.

What is in 1.0

• 128 factory patches, levelled by their TRIM, including the new #25 DRIVEN SAW (a driven lead that uses both filters). 15 factory multis and the CPU test M16, 32 patterns in one list.
• Two filters on every engine: the MULTI FILTER and the TWIN FILTER (types OFF, LP, BP, HP, NOTCH, LADDER, COMB; DRIVE, SERIES or PARALLEL, BLEND, LINK with the offset in whole semitones). A SUB OSC layer, WAVE STEPS and a CYCLE envelope.
• Two cores: part 2 plays on the chip's second core from every power-on, with an automatic fallback to one core if it does not answer or misbehaves.
• The update screen: while the firmware is written the unit shows DUELL over moving wave lines, WRITING, the percent, a bar of 20 segments and DO NOT SWITCH OFF.
• MIDI CC map with 70 direct CCs (list in the README), MIDI LEARN for the rest.
• Key velocity and aftertouch (menu: AFTERTOUCH on, KEY VELOCITY off by default).
• Web editor with the ENGINE selector, the patch library, the multis, a piano roll, wavetable files, DX7 .syx import and a Backup page.
• Morph: ROLL, UNDO and AMOUNT, an End B you can set by hand.
• Effects: per part distortion, INSERT, EQ, ducker; chorus, a delay with four modes, six reverbs, BASS MONO, a master compressor and a stereo WIDTH.

Changed since the 0.2.20 beta (the last public one)

Everything of the 0.2.21 to 0.2.33 test builds is in CHANGELOG.md. The ones you will notice first:

• The bank is new (128 patches); patch numbers changed, a slot you never saved shows the factory sound at its place.
• The two filters are called MULTI FILTER and TWIN FILTER everywhere.
• The MENU > SYSTEM > TEST screen is not in this release; M16 STRESS TEST stays as a multi you may overwrite.

Read this before you flash

• DUELL has run on only one FM-1, the author's. Other units are untested. The way back to the official firmware (V15) has worked on that unit; it is not tested elsewhere. The FM-1 has a single copy of its firmware and no known rollback.
• You install at your own risk. No warranty (GPL-3.0). Use a data USB cable straight into the computer and never interrupt the write.
• DUELL is not affiliated with M-VAVE. M-VAVE's firmware is not distributed here: to go back you download V15 yourself from https://www.m-vave.com/download.
• Recovery notes: docs/RECOVERY.md.

Assets

File	What
duell-1.0.fwsc	the device package (the installer page loads this one)
SHA256SUMS	checksums

SHA256: f0fd3b46ec013febc8585fa153f782a7414a0b84e9bfe4f1da8147cfe83ba462  duell-1.0.fwsc   (size: 614,666 bytes)

How to install

Open the installer page in Chrome or Edge: https://oscillr.github.io/DUELL/install/. Save a backup, connect the FM-1, press Install and wait for Done; then switch the unit off and on once. Steps: docs/INSTALL.md. The page shows the package's SHA-256 so you can compare it with the one above.

The web editor (Chrome or Edge, unit connected over USB): https://oscillr.github.io/DUELL/editor/.

Known limits

Tested on one unit only; 11 pattern slots share one storage object of 3,584 bytes; some LFO depth destinations are hidden; KEY VELOCITY is off by default; MIDI is not tested with many devices. The whole list: docs/KNOWN_LIMITS.md and docs/KNOWN_ISSUES.md. Bugs: the report form.

Credits

Special thanks to: Felucca and its author Leo Kuroshita, JIANT (reverbs), CHOMPI Club (plate reverb and delay ideas), Emilie Gillet of Mutable Instruments (reverb design), Charles Vestal (Velo, the method for key velocity and aftertouch, and X0X), aquanodemusic (a CC0 FM voice), Baud Girl (for starting it all), keremimo (Melodee), Quixotic7 (ChoralRoot), zvenson (zp12), isod89 (SLOOP), and the whole community. Every third-party part and its licence: CREDITS.md, NOTICE.md.

DUELL MultiMorphing Bitimbral Synthesizer by OSCILL/R

Two synths in one small box. DUELL is free, open-source firmware (GPL-3.0) for the M-VAVE FM-1, a fork of Felucca. A bitimbral synthesizer with two independent parts, playable in three modes. This is a firmware beta: the device package, the web installer, the web editor and the browser emulator.

What is in it

• LAYER: both parts combined, with balance, velocity crossfade and key split. Perfect for complex sounds and DAWless performances.
• DUEL: dual mono. Part 1 hard left, part 2 hard right, fully isolated for use with your external effects.
• STEREO: both parts in one stereo field.
• MORPH: glide between two versions of the same patch with one fader. A smart randomizer creates new variants from your starting point.
• 10 engines, each with a multimode filter. 2 envelopes, 2 LFOs and a mod matrix with 8 slots.
• Ducker (sidechain from MIDI), EQ per part, SAT and INSERT per part (including TAPE, VINYL, FOLD, HARD and CRUSH), chorus, a delay with four modes (DIGI, PING, RAND, OCT+), and six reverbs: ROOM, SPRING, HALL, SHIM, RESO and PLATE, with a low cut on the reverb input.
• BASS MONO (its own page on the GLO button): the output is mono below a frequency you choose (STEREO and LAYER).
• Two level controls per part, as on a hardware synth: the sound's own TRIM and your mixer LEVEL.
• MIDI: a channel for each part, clock in (AUTO, INT, USB or TRS), program change, bank select.
• 128 patch slots, filled by the factory sounds (save over any slot, RESTORE brings the factory sound back), 16 MULTIs (both synths in one slot) and 16 patterns.

New since 0.2.13

• Web editor at https://oscillr.github.io/DUELL/editor/: a patch library for the 128 slots (export, import, drag between slots, DX7 .syx import), backup and restore, a piano roll for the step patterns, and wavetable files.
• 3 user wavetables (USR1 to USR3) for the WAVE engine, made from a WAV file.
• 128-patch bank with SAVE over any slot, RESTORE and RESTORE ALL (it was 48 places).
• 14 new factory sounds (the bank grows from 114 to 128) and 3 more FM6 voices.
• TAPE and VINYL, two new INSERT types.
• PLATE, a sixth reverb, and a LOCUT on the reverb input so no reverb makes the bass muddy.
• Delay modes: DIGI, PING, RAND and OCT+.
• SHIMMER: the SHIM reverb can shimmer an octave down or both ways (PITCH), with a slow drift (MOD).
• BASS MONO, on its own page of the GLO button (not in the MENU): the output is mono below a frequency you choose.
• KILL, a new 4-pole filter on PERFORM (no noise, no crackle), PERF LEAVE (SPACE and KILL glide back to neutral when you leave PERFORM, or KEEP), and the black keys play in the scale on PERFORM.
• MODULES: switch the arp, the sequencer, the send effects and the part effects off for the whole unit (GLO).
• STOP ALL now silences the delay, chorus and reverb tails too.
• The unit shows up as DUELL over USB. Computers may treat it as a new device once (the MIDI port names change).
• CLK AUTO: the clock finds itself (USB or TRS) and falls back to the internal tempo; it is the new default.
• MIXER and the pages reordered: a mode or type first, an amount next, a level or mix last. Controls that do not apply are hidden instead of faded.
• K1 acceleration on the patch list: a fast turn goes faster through the 128 slots.
• Installer backup fixed: it works with DUELL again and saves patches, multis, patterns, wavetables and settings.
• The hottest audio code runs from the chip's RAM instead of the flash.
• Level model: TRIM (the sound's loudness, saved with the patch) and LEVEL (your mixer volume, never touched by loading a sound).
• Removed: OUTPUT EQ (the low cut and BASS+) and the OVERVIEW page. TUNE stays in the MENU (MENU > AUDIO).

Full list: CHANGELOG.md.

Read this before you flash

• This is a beta. It has been tried on only one FM-1, the author's. Other units are untested.
• Saves may change before the alpha. Until the alpha release, the way patches, multis, settings and backups are saved may change. Saves may stop loading between versions. Do not rely on them yet.
• Saves from before 0.2.20 will not load after the update. Patches, multis and projects saved with 0.2.13 or any earlier version are not read by 0.2.20 (nothing is converted); the slots show the factory sounds and multis. Back up first, and do not count on getting your old saves back.
• The factory sounds, plus 14 new ones. FRETLESS and SLAP DOCTOR were reworked (they no longer sound alike), the sound numbers changed (a sound's number is its place in the list), and the reverb has a new low cut default (88 Hz), so a reverb has a little less bass than in 0.2.13.
• The FM-1 has a single-bank layout and there is no known rollback. The way back to the official firmware (V15) has worked on the author's unit about three times; it is not tested elsewhere.
• You install at your own risk. No warranty (GPL-3.0). Back up first, use a data USB cable straight into the computer, and never interrupt the write.
• DUELL is not affiliated with M-VAVE. M-VAVE's firmware is not distributed here: to go back you download V15 yourself from https://www.m-vave.com/download.
• Recovery notes: docs/RECOVERY.md.

Assets

File	What
duell-0.2.20-beta.fwsc	the device package (the installer page loads this one)
duell-emulator-0.2.20-beta.zip	the browser emulator (also hosted at https://oscillr.github.io/DUELL/emu/)
SHA256SUMS	checksums

SHA256: bdb12cf2b476124b7b82f2cacdf6ed6a047f33a550eb74a0434183dd527f4478  duell-0.2.20-beta.fwsc   (size: 610,086 bytes)
SHA256: 404d7f334fb8ffcfd673c8a6443a8f62230f1ec4e91fdf5f2c1c6f7e1dbb72c8  duell-emulator-0.2.20-beta.zip   (size: 330,987 bytes)

How to install

Open the installer page in Chrome or Edge on a computer: https://oscillr.github.io/DUELL/install/. Tick the checklist, save a backup, connect the FM-1, press Install and wait for Done; then unplug and replug the unit. Steps and details: docs/INSTALL.md. The page compares the file with the SHA-256 above.

The web editor (Chrome or Edge, unit connected over USB): https://oscillr.github.io/DUELL/editor/.

Known gaps

• Tested on one unit only (the author's). The editor and the restore are not tested with many units.
• The patch library and the piano roll are tested on the computer (simulated unit). The USB-MIDI timing of a 128-patch export or import (PATCH_RAW) and the flash timing of 128 writes are not measured on a real unit yet.
• The user wavetables are tested on the computer; their writes are not tested on other units.
• A heavy multi can click when it is loaded (a missed audio block, very rarely).
• MIDI is not tested with many devices; dual core is off and untested.

All of it in docs/KNOWN_ISSUES.md. Bugs: the report form.

Credits

Special thanks to: Felucca and its author Leo Kuroshita, JIANT (reverbs), CHOMPI Club (plate reverb and delay ideas), Emilie Gillet of Mutable Instruments (reverb design), aquanodemusic (a CC0 FM voice), Baud Girl (for starting it all), Charles Vestal (X0X), keremimo (Melodee), Quixotic7 (ChoralRoot), zvenson (zp12), isod89 (SLOOP), and the whole community.

The PLATE reverb is based on the reverb of the CHOMPI firmware (MIT), which is Emilie Gillet's plate reverb from Mutable Instruments Rings and Clouds (MIT). The RANDOM and OCT+ delay modes are written again from the idea of the granular delay of CHOMPI Club's TEMPO firmware (MIT); no code copied. Licence notices: NOTICE.md.

DUELL MultiMorphing Bitimbral Synthesizer by OSCILL/R

Two synths in one small box. DUELL is free, open-source firmware (GPL-3.0) for the M-VAVE FM-1, a fork of Felucca. A bitimbral synthesizer with two independent parts, playable in three modes. This is a firmware beta: the device package, the web installer and the browser emulator.

What is in it

• LAYER: both parts combined, with balance, velocity crossfade and key split. Perfect for complex sounds and DAWless performances.
• DUEL: dual mono. Part 1 hard left, part 2 hard right, fully isolated for use with your external effects.
• STEREO: both parts in one stereo field.
• MORPH: glide between two versions of the same patch with one fader. A smart randomizer creates new variants from your starting point.
• 2 envelopes, 2 LFOs and a mod matrix with 8 slots. Every engine has a filter.
• Ducker (sidechain from MIDI), EQ per part, ping-pong delay, and the SHIM and RESO reverbs.
• MIDI: a channel for each part, clock in, program change, bank select.
• 114 patches, 16 MULTIs (both synths in one slot) and 16 patterns.

New since 0.2.4

• WAVE, a wavetable engine.
• PERFORM mode: hold FX, and the white keys are effects that last while you hold them.
• A multimode FILTER page (CUT, RES, MODE, SLOPE) on every engine.
• Quick edit layers: hold EDIT, LFO, ENV, ARP or GLO.
• HOLD with three values (OFF, ARP, ALL); outside the sequencer pages a tap of REC is HOLD.
• Hold OCT- and turn a knob to reset that knob.
• A first-start guide.
• 10 factory multis (M01 to M10).
• The step sequencer snaps its notes to the scale.
• SPACE, one knob for room and width (PERFORM and the MIXER page).
• A small CPU meter bar in the header.
• SAMPLE, GRAIN and SLICE are removed; WAVE replaces them.

Full list: CHANGELOG.md.

Read this before you flash

• This is a beta. It has been tried on only one FM-1, the author's. Other units are untested.
• The FM-1 has a single-bank layout and there is no known rollback. The way back to the official firmware (V15) has worked on the author's unit about three times; it is not tested elsewhere.
• You install at your own risk. No warranty (GPL-3.0). Back up first, use a data USB cable straight into the computer, and never interrupt the write.
• DUELL is not affiliated with M-VAVE. M-VAVE's firmware is not distributed here: to go back you download V15 yourself from https://www.m-vave.com/download.
• Recovery notes: docs/RECOVERY.md.

Assets

File	What
duell-0.2.13-beta.fwsc	the device package (the installer page loads this one)
duell-emulator-0.2.13-beta.zip	the browser emulator (also hosted at https://oscillr.github.io/DUELL/emu/)
SHA256SUMS	checksums

SHA256: f0c2f71db9bdcfc7fd84f9d8ceae0eb3cdad1d080247ab30eabe7d99c997ed1c duell-0.2.13-beta.fwsc (size: 610,086 bytes) SHA256: 3d7d7c14ab9fd8202ca5d2e6318ebd0164cbb2fdf49dc5b74a501766c8a92cd0 duell-emulator-0.2.13-beta.zip (size: 349,348 bytes)

How to install

Open the installer page in Chrome or Edge on a computer: https://oscillr.github.io/DUELL/install/. Tick the checklist, save a backup, connect the FM-1, press Install and wait for Done; then unplug and replug the unit. Steps and details: docs/INSTALL.md. The page compares the file with the SHA-256 above.

Known gaps

• The backup does not include MULTIs and PATTERN slots; restore is untested.
• Very rarely a short click (a missed audio block) when switching to a very heavy multi.
• The editor in the source tree is not adapted to DUELL.
• Tested on one unit only; MIDI is not tested with many devices; dual core is off and untested.

All of it in docs/KNOWN_ISSUES.md. Bugs: the report form.

DUELL MultiMorphing Bitimbral Synthesizer by OSCILL/R

Two synths in one small box. DUELL is free, open-source firmware (GPL-3.0) for the M-VAVE FM-1, a fork of Felucca. A bitimbral synthesizer with two independent parts, playable in three modes. This is the first firmware beta: the device package, the web installer and the browser emulator.

What is in it

• LAYER: both parts combined, with balance, velocity crossfade and key split. Perfect for complex sounds and DAWless performances.
• SPLIT: dual mono. Part 1 hard left, part 2 hard right, fully isolated for use with your external effects.
• STEREO: both parts in one stereo field.
• MORPH: glide between two versions of the same patch with one fader. A smart randomizer creates new variants from your starting point.
• 2 envelopes, 2 LFOs and a mod matrix with 8 slots. Every engine has a filter.
• Ducker (sidechain from MIDI), EQ per part, ping-pong delay, and the SHIM and RESO reverbs.
• MIDI: a channel for each part, clock in, program change, bank select.
• 97 patches, 16 MULTIs (both synths in one slot) and 16 patterns.

Full list: CHANGELOG.md.

Read this before you flash

• This is a beta. It has been tried on only one FM-1, the author's. Other units are untested.
• The FM-1 has a single-bank layout and there is no known rollback. The way back to the official firmware (V15) has worked on the author's unit about three times; it is not tested elsewhere.
• You install at your own risk. No warranty (GPL-3.0). Back up first, use a data USB cable straight into the computer, and never interrupt the write.
• DUELL is not affiliated with M-VAVE. M-VAVE's firmware is not distributed here: to go back you download V15 yourself from https://www.m-vave.com/download.
• Recovery notes: docs/RECOVERY.md.

Assets

File	What
duell-0.2.4-beta.fwsc	the device package (the installer page loads this one)
duell-emulator-0.2.4-beta.zip	the browser emulator (also hosted at https://oscillr.github.io/DUELL/emu/)
SHA256SUMS	checksums

783bcc49b0ba02c2c105d5f2b1e6b4d96538c85ef85a900ab796d1b6f77df4f6  duell-0.2.4-beta.fwsc
7775abee8f30679331d5e09f5b5433b7525a2a1392a3ff2d3e822a8186ea87af  duell-emulator-0.2.4-beta.zip

How to install

Open the installer page in Chrome or Edge on a computer: https://oscillr.github.io/DUELL/install/. Tick the checklist, save a backup, connect the FM-1, press Install and wait for Done; then unplug and replug the unit. Steps and details: docs/INSTALL.md. The page compares the file with the SHA-256 above.

Known gaps

• The backup does not include MULTIs and PATTERN slots; restore is untested.
• Very rarely a short click (a missed audio block) when switching to a very heavy multi.
• The editor in the source tree is not adapted to DUELL.
• Tested on one unit only; MIDI is not tested with many devices; dual core is off and untested.

All of it in docs/KNOWN_ISSUES.md. Bugs: the report form.

DUELL MultiMorphing Bitimbral Synthesizer by OSCILL/R

This is the first public beta of DUELL, a free, open-source bitimbral firmware for the M-VAVE FM-1. It is based on Felucca.

What is in this release The browser emulator only. Download the zip, or just open the hosted version at https://oscillr.github.io/DUELL/emu/ once the page is live.

• Two complete parts, playable in three modes: LAYER, SPLIT and STEREO
• MORPH between two versions of every patch, with a smart randomizer
• 12 sound engines and a factory palette of about a hundred sounds
• Two envelopes, two LFOs and an 8-slot modulation matrix
• Ducker with MIDI sidechain, EQ per part, ping-pong delay and the SHIM and RESO reverbs
• 16 multis and 16 patterns

What is not in this release There is no firmware download yet. The firmware has run on one real FM-1, but the way back to the official firmware has not been tested yet, and more hardware testing comes first. Please do not try to flash anything for now.

Good to know

• The emulator keeps its data in your browser. After an update, clear the site data for the page. "Download saved data" makes a backup first.
• Browser MIDI forwards notes, CCs and program change, but not clock or SysEx.

Feedback Bug reports and ideas are welcome in the Issues tab. There is a bug form with the details that help most. Please say which browser and which part of the emulator you used.

DUELL is licensed GPL-3.0-only, like Felucca. No warranty. It is not affiliated with or endorsed by M-VAVE. Thanks to Baud Girl, Leo Kuroshita and the whole community. The SHIM and RESO reverbs come from JIANT.

SHA-256 of duell-emulator-0.1-beta.zip: cba20fc695f3fed335b52ebd077d0a791cfe06b7662257ee7678295382a4d52f