SLOOP 2.4

Six-operator FM with DX7 patches, parameter locks, micro timing, fills, a quick chain of sections, the sequencer to MIDI out, longer steps and dotted delays, a redesigned web editor, your own drum kits and a 4th sample slot, a full-screen visualiser, CHORD+ chord modifiers with strum, a filter on each track, bigger values, SELECT to turn the pages, and drums programmed with the keys. Most of it comes from your comments: thank you.

New: the complete guide. GUIDE.md covers every button, key combination, layer, page, engine and editor page, with a one-page cheat sheet at the end.

New

FM6: six-operator FM, DX7 patches. A tenth engine: the classic six-operator FM of Dexed (msfa, by Google Inc. and Pascal Gauthier), as Leo Kuroshita ported it to whole-number arithmetic for Felucca 1.0. 32 algorithms, a full patch per track, six voices per track.

• Eight factory patches in the sound bank: TINE EP, GLASS BELL, ROUND BASS, BRASS SECT, SOFT PAD, WOOD BARS, DRAWBARS, NYLON PICK.
• On the FM-1, the eight EDIT values are macros on top of the patch: ALG, FB, MLVL (brightness), MRAT, MEG, VMOD, DTUN, and PTCH, which loads a patch (F1–F8 factory, B1–B27 your bank).
• In the web editor (Sound tab, on an FM6 track): edit every operator, send it to the track, store it in the bank. Import SysEx reads a DX7 file, one voice or a 32-voice bank, so DX7 and Dexed patches play on the FM-1. Export SysEx writes them back.
• DIGITAL, the 4-operator FM, is still there, unchanged.

Parameter locks. In the SEQ layer, hold a step: PRESETS gives one sound parameter another value for that step only, and ALGORITHM picks which parameter (it starts with the last one you turned). You get 24 locks per track, and a step can hold several. At the next step without a lock the parameter comes back.

Micro timing. Hold a step: KNOB 4 nudges it off the grid, from half a step early to half a step late, in 1/64 of a step. On the drum track the whole step moves.

Fills. Hold a step: OCT+ makes it fill only (plays only during a fill) or no fill (silent during one). Then GLO + key 9 plays a fill while you hold it, and key 10 plays a fill on the whole next bar.

Quick chain. Hold SAVE and tap several sections (A B B C, up to 8). When you let go, they play in turn, each for the length of its pattern, round and round.

Clock only. GLO → SYSTEM → IN = CLOCK makes SLOOP follow the MIDI clock (and START / STOP / CONTINUE) while ignoring incoming notes. This is handy when a DAW or a sequencer also sends notes to other gear. NOTES, the default, takes both, as before. This is a setting of the FM-1. Thanks to the community for asking!

The sequencer to MIDI out. GLO → SYSTEM → MIDI = SEQ sends what the sequencer, the arp and the rolls play to USB MIDI too: each track on its channel, the drums on 10. Use it to drive another synth or record the notes in a DAW. Every note is ended, STOP ends what is still on, and notes that came in from MIDI are never sent back. With KEYS (the default), only the keys go out, as before. This is a setting of the FM-1.

A filter on each track. One knob, FILT: turn it left for a low-pass, right for a high-pass, and leave it in the centre for off. Every synth track and the drums have one. It is on the new FX → FILTER page, and live under FX held + KNOB 4 for the selected track. You can lock it on a step, it stays when you change the sound, and it is saved with the project. Thanks for the idea!

Bigger values. The pages without a graph (EDIT, VOICE, ENV DEST, LFO DEST, GLOBAL, MASTER, SYSTEM, FILTER…) now use the empty middle of the screen. Their four values show in large type, placed as the knobs are, and the one you turn shows in white. Thanks for the idea!

SELECT turns the pages. On a page (ENV, LFO, FX, EDIT, ARP, SEQ, SCL, GLO, SAVE), SELECT goes to the previous or next page of that group, so you no longer press LFO again to reach LFO DEST. On HOME, and while you hold a layer, SELECT is still the tempo. Thanks for the idea!

Drums with the keys. On the drum grid page (SEQ tapped on the drum track), the white keys are the 16 steps of the sound that KNOB 1 picks: press a key to set its step, press it again to clear it. The first four black keys pick the page of steps. You hear what you pick: the sound when KNOB 1 changes it (on the grid, and in the SEQ layer), the step's sounds when KNOB 2 moves to it, and the sound when a key sets a step. SELECT switches between grid and kit. Thanks for the idea!

Longer steps, dotted delays. DIV goes to 1/2, 1BAR and 2BAR. The delay's TIME gains 1/8D and 1/16D.

Your own drum kits, and a 4th sample slot. There is a new sample slot, USR4, in flash that was never used before. The drum track's KIT now goes on to USR1–USR4 and USR3+4. USR3+4 is a big kit of about 15 s spread over two slots, so USR1 and USR2 stay free for your instruments.

Build a kit on the editor's new Drum kit page, in three steps:

1. Drop WAVs on 16 pads (KICK, SNARE, HAT, OPEN HAT…), or choose several files and they are sorted by name. Set pitch, gain and length for each pad, and hear it.
2. Choose where the kit goes: USR3+4 (the big kit) or a single slot. The page shows what each slot holds now and what a send would replace.
3. Send the kit. Use on the drum track picks it for you.

Steps, levels, ratchets, fills, the grid page and MIDI on channel 10 all work as with the other kits. Kits can be saved and shared as a ZIP. Thanks for the idea!

A new web editor. The editor is rebuilt to look and feel like the FM-1: its black screen, the four track colours, and its own pixel font.

• Each button's pages are rows of four coloured knobs, as on the screen. You can drag values like knobs.
• The four tracks sit at the top, and the steps look like the device's tiles.
• The pages are grouped in a side bar.
• The Samples page now works in three steps: choose a slot, make the sound (from files, with a picture of which keys play which file, or by chopping a recording), then send it. Play this slot on track 1, 2 or 3 sets that track up for you.

Everything it did before is still there.

The visualiser. On the TRACKS screen, tap HOME: the whole screen becomes a visualiser of what SLOOP plays. SELECT changes the style, and there are twelve: oscilloscope, spectrum, spectrogram, Lissajous, VU meters, circle, tape, LCD, bounce, orbit, wires, and the SLOOP logo itself coming alive (the sail's four bands are your tracks, the dial is the mix's level, and the boat rocks on the sound). HOME again closes it. The keys, PLAY, REC and the layers keep working, so you can play with it on screen. It shows the sound as if MASTER were all the way up, so it keeps moving even with the volume turned down to 0.

CHORD+. Inspired by HiChord and minichord. With a chord mode on (SCL → KNOB 1 CHORD), the black keys now change the chord: hold one while you play a white key, or press it while the chord is held and the chord changes under your finger. F# switches major ↔ minor, G# adds the 7th, A# makes it sus4, C# adds the 9th, D# inverts it. Hold several to combine them; the 7th and 9th come from the scale (in C major, the V chord G with G# is G7, with F# + G# Gm7). What you play is recorded as it sounds. The new SCL 2 page has STRUM, which spreads a chord's notes like a strummed guitar (1–60 ms a note: right for low to high, left for high to low), on the keys and on the chord steps. It also has VLEAD, which voices each chord nearest the last one, so a progression moves smoothly instead of jumping. MIDI out sends the chord's notes together, without the strum. Thanks for the idea!

The menu in sections. Hold HOME: the settings are now grouped as SCREEN, LIGHTS, AUDIO and SYSTEM. SELECT turns the sections as it turns the pages, and KNOB 1, 2 and 3 set the section's rows directly, with the values in large type.

Lights. HOME menu → LIGHTS → KEYS has a new option, ALL KEYS, that makes every key glow. With NOTES on, the sequencer's short notes now light their keys: each note stays lit about a tenth of a second, as drum hits do. Before, a 1/16 note could end between two screen frames and never show.

Fixes

• A MIDI START from a DAW during the REC count-in now starts and records at once. It used to leave SLOOP armed and silent.
• Swing no longer shuffles the triplet divisions (8T, 16T). It used to delay a different note on every beat.
• Turning DIV or the arp's RATE in the first beat after PLAY no longer skips a step.
• In the SEQ layer, KNOB 2 (DIV) now goes on to 1/2, 1BAR and 2BAR, as the PATTERN page does.
• The editor no longer writes presets or a preset bank to flash while the song plays, which caused a short drop-out. It asks you to stop first, as the FM-1 does.
• Filter values of 10 kHz and up show their unit ("12 kHz").
• The boot screen shows the whole logo: the tail of the "p" in sloop was cut off.
• On the SEQ → STEP page, turning ALGO to the drum track no longer draws the drum pattern as a garbled piano roll. The page now says DRUM TRACK, as the other pages the drums have no use for do.
• Fixes that Felucca 1.0.2 to 1.0.3.1 found, checked in SLOOP and fixed the same way (thanks to Leo Kuroshita and spinkham):
  • A knob turned just as you let go of a layer (FX, EDIT, SCL, GLO…), or while you press PLAY in one, no longer changes the page under it.
  • The processor's divide-by-zero trap is off. A compiler quirk could otherwise crash the FM-1 into UBOOT on a divide that the code guards against.
  • Mac users: the serial console is now off by default (HOME menu → USB SERIAL), so macOS 13–15 show the USB audio input. Turn it on only if you need the console, and restart the FM-1 after a change.
  • The editor's Import SysEx reads damaged files (cut short, several banks in one file, a wrong checksum). When a file has no DX7 voice, it says why (4-operator voices, another maker's SysEx…).

Install

Connect the FM-1 by USB, open the web installer in Chrome or Edge and press INSTALL. You can also run python tools/fm1_install.py sloop-2.4.fwsc. Your projects, user presets, samples and settings are kept, and projects, autosaves and backups from 2.3 load as they are.

Going back to 2.3: 2.3 cannot read projects saved by 2.4 (they look empty there, and its autosave can write over the music in progress), and a 2.4 backup restores into 2.4 only. Save a backup with the editor before you go back, then restore it when you return to 2.4.

Beta: install at your own risk. Bluetooth MIDI is still not supported. To go back to the official firmware, use the installer page or M-VAVE's M-UPGRADE.

Thanks to Leo Kuroshita (@kurogedelic) for Felucca and its FM6 engine, and to everyone who commented, reported a bug or asked for a feature.

Files

• sloop-2.4.fwsc: the firmware package