A groovebox is a drum machine and a synthesizer in one box, built to make loops. You build a short loop, called a pattern. You change it while it plays. Then you line patterns up into a song. You don't need a computer for any of this, and the music keeps playing while you edit patterns and sounds.

Firmware is the program that runs inside a device. The Drumboy Pro loads new firmware from its SD card, so installing Nemesis needs only a card reader. You can go back to the original firmware at any time, and Installing, page shows how.

Nemesis is an independent project, not made by Randomwaves. It is free, and this manual describes Beta 2, a test version.

You can try it before you install anything. The website has Online Nemesis, which runs the firmware's own code in a browser, and a tutorial of 16 lessons. See The web tools, page .

This is Beta 2, an early test version. It works on the devices it has been tried on, but expect bugs, and things may change in the next version.

The voice, the sequencer, the effects, the seven parts, saving to the card and recording have all run on a real Drumboy Pro. Slices have mostly been tested on a computer so far. The MIDI sockets have carried notes both ways, clock out and the librarian on a real cable. The newest features, such as the tracker, deleting a project and exporting a song, have had the least time on real hardware.

Saving to the card was built with care, and The card, page explains how. A save is meant either to finish or to leave the version before it in place. That is what the design aims at. It is not a promise. Power cuts have only been tried in simulation, never on a real card, and a card can simply fail. So keep a copy of your card on a computer, and make a fresh copy now and then.

The preset librarian on the website has read a Drumboy over a real MIDI cable, but sending and deleting presets have not yet been proven. The web tools, page says what you can use today.

The knobs

The four knobs above the screen are T1 to T4, and the four below are B1 to B4. They turn without end, and the screen shows the value. Each knob's job changes with the screen, and the box beside it always says what that job is.

On a knob with a wide range, hold SHIFT while you turn for bigger steps: six at a time.

The screen

A box that shows a setting has a coloured label. A box marked INFO only tells you something, and turning its knob says so. A box that does nothing is empty and dark.

The top left corner says which screen you are on, and L BACK. The top right shows play or stop, and the tempo on screens that have no tempo knob. The bottom left shows the pattern, and the bottom right the part.

Getting back

LBACK goes back one level. Hold it for a moment and it goes home from anywhere. SHIFT with LBACK goes home at once. So you can't get lost.

Pressing the key of the page you are on also goes back. On the SLICE page the first press opens SLICE EDIT.

Top of the panel

LINE is the audio input and output, HP the headphones, and MIDI and SYNC are small sockets for in and out. Nemesis uses the line input for recording, the MIDI sockets for notes and clock, and the SYNC sockets for clock. The USB-C socket is for power: Nemesis has no USB MIDI.

Lanes

There are ten lanes in every pattern. A lane holds up to 32 steps, a rhythm, a root note, a level, a mute, and an arpeggio. On a sampler part it also holds its own sample and sound pages.

Select a lane with key 1 to key 10 on the home screen. +UP, −DOWN, ◁LEFT and ▷RIGHT step through them too. Selecting changes nothing you can hear. It says what the knobs and keys work on.

Lanes in a pattern keep their own settings, so a lane's rhythm in P2 has nothing to do with the same lane in P1.

Parts

There are seven parts, A to G. A part is one instrument, and each is either a synth or a sampler.

A synth part has one sound, on nine pages, shared by all its lanes. Three lanes on one synth part are three rhythms on one instrument. Parts belong to the project, so a synth's sound is the same in every pattern.

A sampler part is different: each of its lanes has its own sample and its own sound pages, so one sampler part can be a whole drum kit. A drum lane's sample belongs to the pattern.

A synth part has 1 to 5 voices and a sampler part 1 to 8. A voice is one note sounding. Parts each have a colour, and it is the same on every screen.

Moving a lane to another part

On the home screen T3 says PLAYED BY. It is a setup move, so a stray turn does nothing but tell you how: hold SHIFT and turn T3. Parts D to G are spare synths, ready for when you give one a lane. A lane on a synth part plays notes. On a sampler part it plays its own sample, and notes become pitch.

Making a part a sampler or a synth

Press FFILE and find the INSTRUMENT box on T4. Hold SHIFT and turn it. T3 picks the part first. This changes only the part's type, and SHIFT with ○CLEAR undoes it.

LENGTH, HITS and ROTATE

Every lane has three numbers. LENGTH is how many steps it has. HITS is how many of them play. ROTATE slides the rhythm along the lane. Turn any of them and the lane changes at once: LENGTH and HITS on the home screen or in the step editor, ROTATE in the step editor. Three hits in eight steps give x..x..x.

ADD rolls the dice

●ADD gives the selected lane a new Euclid rhythm: a random number of hits and a random rotation. Press it until you like what you hear. SHIFT and ○CLEAR do not take this back, so note it down if you like the one before.

Lengths that differ

Lanes keep their own lengths against a shared clock, inside the pattern. A lane of 12 under a lane of 16 starts again after 12 steps, so its first four steps fall against the end of the other lane. When the longest lane ends, every lane starts again from step 1, so the pattern repeats exactly. A pattern lasts as long as its longest lane.

Tapped steps

A tap on a step flips it: a silent step plays, and a hit goes silent. Tapped steps are kept apart from the rhythm, on top of it. So you can change HITS later and keep your hand-made changes.

Clearing

• ○CLEAR once removes your taps and leaves the rhythm.
• ○CLEAR again, quickly, turns the rhythm off too, so the lane is empty. Turning HITS brings the rhythm back.
• ○CLEAR held for a second, on the home screen or in the step editor, empties every lane in the pattern: rhythm, taps, locks and slice SYNC. The lanes keep their sounds, levels and mutes.
• SHIFT with ○CLEAR brings back whichever of these you did last.

A step's locks stay with the step, not with the rhythm. If you move the hits, a lock may land on a silent step. It is kept, and used again when the step plays.

A press, a tap and a hold

Pressing a step key selects it at once. What happens next depends on you:

• Tap it and let go: the step switches on or off.
• Hold it and turn a knob: that knob edits that step, and the step stays as it was.
• Hold it for about a third of a second and let go without turning: its lock opens (P-locks in full, page ).

What a step holds

A step's NOTE is an offset from the lane's ROOT, up to two octaves either way. With a project scale set, the box beside it shows the note that really sounds. VELOCITY is how hard it plays. GATE is how long it is held, counted in steps, so 1.00 is one step long. PROB is the chance that it plays at all, thrown again each time it comes round.

How the arpeggio plays

On a step with a chord, the arpeggio walks the chord's notes across the octaves you set. On a single note it repeats that note, which makes a ratchet, a fast repeated hit. UP/DN goes up and comes back, and RAND picks any note of the set.

ARP RATE, ARP OCT and ARP GATE are dark while ARP is OFF. INVERSION, VOICING and STRUM are dark on a step with no chord, and STRUM is dark with an arpeggio on.

Chords on a sampler lane

A chord on a sampler lane plays pitched hits of the lane's sample. The sampler's second view has no chord knob, so a step keeps a chord it had before, and the tracker's popover says so.

With a project scale

With a scale set on PROJECT, each note of a chord is moved into the scale one by one, so chords become diatonic: they use only notes of the key. See Key and scale, page .

Limits

A step's note stays within two octaves of the lane's root. An octave move that would leave that does not happen at all, because stopping at +24 would change the note. A semitone stops at the limit. Either way the popover says STOPPED in red. Octaves wider than that belong to the lane's ROOT.

IN SCALE

IN SCALE is offered on T4 once PROJECT has a scale, and it is off by default. When it is on, NOTE and ‖‖OK with ◁LEFT or ▷RIGHT walk only the notes of the scale, so every click is a note you can hear change. It is how you are working, not part of the song, so it is not saved. Sampler lanes have none.

Undo and locks

Undo is one level, as elsewhere. Everything done to a step while its popover stays open counts as one undo. A lock works as in the step editor: hold a key 1 to 10, let go, and pick a page. +UP and −DOWN leave it open, and another lane closes it.

What it does not do

Entering a note makes no sound of its own: you hear a note when the pattern plays it. Arrow keys do not repeat when held. ‖‖OK on a filled step does not copy its chord: the last note is a note.

Setting one

1. Open the step editor or the tracker.
2. Hold a step key for about a third of a second and let go. The lock opens, and the corner of the screen turns yellow.
3. Open any sound page, or the FX screen's SENDS or AMP SIM views.
4. Turn a knob. Its box turns lime and reads LOCK.
5. Tap the same step key to close the lock. On a sound page keys 1 to 8 are always the step editor's steps, so a lock opened in the tracker is closed back in the tracker, or by holding LBACK.

Quick moves

While a lock is open, tap another step and the lock moves there, which makes it quick to lock the same knob across several steps. Holding a step and turning a knob on a sound page with a lock open edits that held step's lock. A lock stays open while you move between sound pages.

Seeing them

Steps with locks have a mark on the home grid, a lime mark in the tracker, and LK with a number in the step editor.

Clearing

With a lock open, ○CLEAR removes that step's locks. In the tracker, ○CLEAR with no lock open removes the whole step. A lock that no longer has a hit is kept, and used again when the step plays.

Eight to a step

A step holds up to eight locks. A ninth says A STEP HOLDS 8 LOCKS. A sample on a step and a slice on a step each count as one.

Choosing one

Turn WAVE, T1 on OSC 1 or OSC 2, past SIN, TRI, SAW and SQR. The banks the card has come next, by name. The knob skips banks the card does not have. A bank's file is loaded when you pick it.

POSITION

With a bank chosen, PD SHAPE becomes POSITION, from 0 to 100% across the table, and PD AMT is dark. POSITION can be locked to a step, so each step can play another place in the table. The LFO's PD AMT destination and ENV>PD move it too, for tones that change while they sound. WAVE itself can't be locked.

What the card holds

The numbering has 200 banks. The install package holds the banks that the presets use, in CATHODE/WT. A bank has 32 frames, a few have 16, and each takes about 1 MB of memory while a part plays it.

When a bank is missing

A bank whose file is not on the card shows its name in red with a question mark, and plays the basic wave it is nearest to. The part still sounds, and the project is not changed.

When memory is full

Up to six banks fit in memory at once, shared with the samples. Past that, or when the samples have taken the room, the screen says WAVETABLE MEMORY FULL and that part plays a basic wave. A bank nobody plays is let go. See Recording, page for how the memory is shared.

About the voice-like banks

The banks called FORMANT, CHOIR, NASAL, THROAT, BREATH, WHISPER and the like give vowel-coloured tones, not voices: their peaks move with the note, as a voice's do not.

What the folder knob changes

Nothing that plays. The lane keeps its sample, and the knob only moves where it is looking. The sample on show is heard once when the knob stops. The first turn of the sample knob, either way, picks the sample on show. To leave without picking, turn the folder knob back, or simply leave it.

A pick is live

The lane plays the new sample at its next hit. SHIFT with ○CLEAR undoes a whole run of turns in one go. At the end of a folder the knob stops and says so.

On a step

A step with no sample of its own shows LANE, the knob's left stop. The first turn right picks the sample last used in that folder, so one sample can go on several steps with one turn each. Turning left past the first sample of a folder takes the lock off.

FILE

FFILE on a sampler part is the same list on a whole screen. It opens in the folder the lane's knob is in. ◁LEFT and ▷RIGHT or CATEGORY change the folder, and CATEGORY also has ALL, the whole list. Nothing changes until ‖‖OK. A folder chosen here is the one the sample knob is in afterwards, and the other way round. Takes are in the folder REC.

Previews

A preview reads the card, which takes a moment. A slow turn is heard at every click, and a fast turn where it stops. A sample over about 12 seconds says TOO LONG TO PREVIEW. It still plays on a lane.

Your own samples

Copy WAV files into a folder under Sample on the card, and they are there at the next start. The list holds 3,072 samples.

STEP

A step plays the slice of its place in the lane: step 3 plays slice 3, so the rhythm picks where the loop is chopped. In the step editor's second view, STEP SLICE locks a slice to a step. A step can lock RANDOM and RND REV too, and every other sampler knob: pitch, filter, level and reverse.

SYNC

The loop runs on the song's clock whatever the lane's rhythm. Each slice falls at its own place in the beats, so the feel stays at any tempo, and swing bends the steps it falls in. The lane's steps still work on top of it: a step's locks reach the slices it holds, STEP SLICE replaces them, and PROB can drop them. STOP and MMUTE end it.

MIDI

On a sliced lane alone on its MIDI channel, keys play the slices from the lane's note up. On a shared channel a lane has one note, so it plays its first slice. Give a sliced lane a channel of its own.

How slices sound together

A lane's slices cut each other, so a chopped loop is one voice. Notes of a chord start together and all sound. With PLAY on LOOP a STEP slice loops inside itself, with the LOOP page's fade, and SYNC slices play once.

SLICE EDIT

Press OSC 2 again on the SLICE page. Now the knobs work on one slice at a time, and once more leaves the page. A run of edits is one undo.

Where slices are kept

Slices belong to the sample, not the lane: every lane on that sample plays the same ones. A project holds the cuts of 16 samples, 32 slices each. If the file changes, the panel cuts it again. A sample missing from the card loses its cut.

AUTO

The search runs when the knobs have stopped. Until it lands the lane plays the knobs' points, and a sound already looping moves to the new points when it next starts. Turning AUTO sets CURVE to MATCH, and you can turn CURVE afterwards. A step that locks START or END plays the knobs' points, with no search.

EQ AMP looks for two rising zero crossings where the wave on both sides of the join is most alike. It often needs no fade at all. Use it on anything with a pitch.

EQ POWER looks for two steady places where the sound is equally loud over the length of the fade, then lines them up as well as the wave allows. Use it where you want a real fade.

So a sound with a pitch wants EQ AMP and no fade, and a sound without one, like noise, wants a fade of 50 ms or more.

Where it is kept

Found points go with the sample, in the project: 32 entries, one for each sample, START, END, AUTO, SEARCH and fade in use. With all 32 in use a further lane stays on its knobs' points. A sample missing from the card loses them.

AUTO capture

AUTO needs the input over the threshold for several samples, so one tick of noise does not start it. The 50 ms before that moment stay in the take, so the attack is not cut off. Keep the threshold above the noise of the source: the meter shows where that is.

What a take is

A take is mono, 16-bit, at 44.1 kHz, and a sample like any other: you can slice it, loop it and lock it. A take that hits full scale says so when it ends: lower GAIN and go again. ●ADD and MMUTE do nothing on this screen, so a slip of the finger does not change the project.

Where it goes

A take is saved as Sample/REC/RECnnnn.wav and read back from the card before it counts as saved. If that fails the message says why, and the take stays in memory only, named UNSAV01 and on. It lasts until the next project load or until the power goes, so a project saved with it cannot bring it back.

After a restart a take over about 12 seconds cannot be previewed, but it plays on a lane.

Memory

Samples and wavetables share one pool. Samples fill it from one end and wavetables from the other, and a recording goes in the free memory between them. So the room for a take is what the project leaves: about 108 seconds on an empty project, less with each wavetable and sample.

The delay, reverb and chorus are shared: there is one of each, and each part decides how much of itself to send to them. The compressor sits on the master, over everything. The amp simulator is per part: each of the seven has its own.

Each view draws what the effect is doing, and redraws with every turn. ○CLEAR puts a view's settings back to their defaults, and for AMP SIM and SENDS that means the part's own. SHIFT with ○CLEAR undoes it.

A shared effect that nothing sends to costs no CPU. On the compressor, ACTIVE switches it. Sends start at 0%, so a new project is dry.

PRIORITY

The third view gives each part a priority: LOW, MID, HIGH or KEEP. It says which parts matter most if the CPU runs short. A new project has A on HIGH, the drums on C on KEEP, and the others on MID.

The budget

The cost of a sound is counted in plain voices. One plain voice is one oscillator through one light filter, and the project's budget is 33 of them. Options add to a voice's cost, and the small numbers in some knob boxes say by how much. A part no lane plays costs nothing. A shared effect that no part sends to costs nothing.

Picking a pattern

T4 on the home screen walks all 16. Hold SHIFT and press key 1 to key 10 for P1 to P10. When stopped, the change comes at once. While playing, it waits for the end of the current pattern, so it always lands in time: T4 shows P1 ▸P5 and the corner ▸P5. Pick the pattern that is playing to stay on it. While a song plays, the song chooses.

FFILL

Hold FFILL and every Euclid lane plays twice its hits, up to its length. Let go and the lane is back.

MMUTE

MMUTE silences the selected lane, and again brings it back. A muted lane keeps its place, so you can take instruments in and out while the music plays. A mute belongs to the lane in that pattern.

CCOPY and PPASTE

CCOPY copies the selected lane, and PPASTE puts it on the lane you are on. The lane keeps its own part. SHIFT with CCOPY and PPASTE does a whole pattern. On the SONG screen they do a whole song. What you copied stays through a project load, so you can carry a pattern into another project.

Making a variation

Copy P1 with SHIFT and CCOPY, pick an empty pattern, and paste with SHIFT and PPASTE. Now change one thing. That is the quick way to a second part of a track.

Undo

SHIFT with ○CLEAR undoes the last big change. There is one level, and each new undoable action takes the place of the one before. The screen says what came back, as UNDONE and its name.

Factory projects

They are in the firmware, so they are there on any card. Nothing can overwrite them. Loading one gives a copy to change and save to a slot, and it keeps its name in its first slot.

F1 DEMO is the sound of the tutorial: four patterns and a song, on bass, lead and drums, at 118 BPM.

F2 TECHNO is F minor at 132 BPM: one acid line, one chord stab, and the rest drums, with all the movement in locks.

F3 MASCHINE is a straight, robotic electro at 124 BPM, where a bass filter steps up on every note, and bleeps are made from the lead by locks alone.

Both new ones use only the built-in samples.

Saving

A slot takes the name PROJECT and its number the first time. Each save reads the newest copy, writes the older one, and checks what it wrote. The card, page tells more. Saving over a slot can be undone until the next undoable action, within this session.

Loading

Loading stops the music. If a load had to fall back on the older copy, the message says LATEST SAVE DAMAGED and THE ONE BEFORE IT. If samples are missing it counts them. A project that uses a preset the card lacks still sounds right, because the sound itself is saved in the project. It only shows no preset name.

Deleting

Delete removes the project from the card and leaves what is in memory alone. There is no copy on the card. The undo is a copy in memory, and it is gone with the power or the next undoable action. A project that cannot be read takes one press more, and says it has no undo.

Loading

A pause on a synth preset plays three notes on a temporary copy, in the project's key. ‖‖OK loads it. A preset from the card brings all nine pages, the voices it was made for, and its sends and amp. A built-in one sets only the knobs named on The synth pages, page , leaves the voices alone, puts the part's sends at 0 and turns its amp off. A shared effect takes the preset's settings only if no other part sends to it. If the voices would not fit the budget with the effects, they are trimmed, and the message says so. FFILE leaves without loading.

A card without the CATHODE folder gives you only the three built-in presets: Iron Squelch, Sub Pressure and Dimension Bloom.

Saving your own

On a sound page or in FILE, hold SHIFT and press ‖‖OK. SAVE PRESET opens for the part you are on. It works on a synth part with no lock open.

Where the files go

To the card, in Export/<project>/, as Song 1.wav, Song 1 lane 08 Kick 808.wav and Song 1.mid. A file already there is never touched: the new one becomes Song 1 (2).wav.

How a render works

A render is silent and can take a while, and the screen shows how far it has come. What was sounding dies away first, so it is not in the file. The song then plays once with its loop off, and goes on until two seconds have been silent, twelve at most, so the effects ring out. Muted lanes stay muted. No MIDI goes out, and what comes in is dropped. Afterwards the pattern and song on screen are as they were.

A render never gives up a voice, so it can hold more than live playing can.

Stems

A stem is the whole song again with one lane let through, so it takes longer. A step's PROB falls the same way in every stem and in the mix. Each stem keeps its effects. The stems do not add up to the mix exactly: the master compressor hears one lane at a time, and a free-running LFO is somewhere else each time.

MIDI file

The notes come from the real sequencer, so Euclid rhythms, tapped steps, chords, strums, arpeggios, swing and the scale are in the file as they play. A step with a PROB plays or not once. Each track is on the lane's MIDI channel, or a channel of its own if the lane's MIDI is off, and a lane's notes are what its MIDI out sends. The notes are on a 480 PPQ grid, 480 ticks to a quarter note. Locks are not in the file. A file holds 24,000 notes at most: a song with more says TOO MANY NOTES FOR A MIDI FILE and makes no file. What plays plays on while the file is made.

On the card

The first write after a start reads the whole card first. Closing a file reads all of it back, which is the CHECKING on the screen. STOP or a full card takes the unfinished file away, and stems finished before that stay. A power cut can leave part of a file: a computer can delete it. Samples that do not fit or will not load are missing from the render, and the message at the end says how many.

On the computer

The web version makes the same files as downloads, and stems arrive as one zip. The librarian page can also ask a Drumboy for a song's MIDI file over the cable, on the same terms as the rest of the librarian (The web tools, page ).

Notes in

A synth lane alone on its channel plays every note at the note's pitch. A sampler lane alone is moved by the note's distance from its BASE NOTE. On a shared channel, a note plays the lane whose trigger note it is: a synth lane at its root, and a sampler lane at its own pitch.

Notes play the part of that lane in the pattern playing, through its voices, with the sequencer running or not.

Notes out

Going out it is the same rule backwards. What a lane plays goes out on its channel: a synth lane its notes, a drum lane alone on a channel its note moved by the step's pitch, and a lane on a shared channel always its trigger note.

Controllers in

• Pitch bend, up to BEND RNG on the part's GLOBAL page.
• The mod wheel (controller 1) opens the filter, by MOD WHL on the MOD page.
• Channel pressure opens the filter, by AFTERT.
• All sound off, all notes off and reset controllers are obeyed.

They go to the part of each lane on that channel, or the part on screen if no lane is.

What is not there

With GLOBAL's CLOCK at INT, Nemesis sends a MIDI clock with start and stop while it plays, and pulses at SYNC out: two to a quarter note, with a gate that is up while it plays. Set CLOCK to MIDI and it follows a MIDI clock: START, CONTINUE and STOP work, each sixth tick is a step, the tempo on screen follows, and it passes the clock on to the MIDI and SYNC outputs. At SYNC it follows two pulses to a quarter note at SYNC in, and passes them on. Swing does not apply to a clock from outside, and PLAY waits for the first tick or pulse. A SYNC pulse has to last at least a millisecond. In a web browser nothing can send a clock, so Nemesis keeps its own there. A sustain pedal holds notes played in from a keyboard. It has no program change and no USB MIDI: the USB-C socket is for power.

What differs from the hardware:

• It starts on the demo project, not an empty one.
• It has the 12 built-in samples and all 200 presets, and no SD card.
• The card is a pretend one, gone when you close the page. EXPORT sends files to your browser as downloads.
• A drum loop stands in for the line input, and a take stays in memory until the page goes.
• There are no MIDI sockets on the page.
• The knobs have stops. Drag one up or down: 160 pixels covers its whole range. The wheel, or the arrow keys on a clicked knob, go one step.
• SHIFT stays down when clicked, until the next key has been pressed.

Tutorial

Sixteen lessons beside the working panel, listed in Where to go next, page . The control to use flashes, and the page waits until the firmware shows you did it. A Show me button can do a step for you. Each lesson starts from a Drumboy as it boots, so nothing you did before can change what it says. Your progress stays in the browser.

The librarian's job is to keep presets on a computer and on the card: list what is on the device, back up one or all as .PRS files, add files from the computer, and delete. It asks before it adds or deletes. Every transfer is checked as a whole, and a transfer that fails is not resumed: the page tells you, and you start it again.

The built-in three are listed and can't be changed. A device can also send a song's MIDI file.

A real connection will need a USB-MIDI interface wired to both sockets, in and out, and a browser with Web MIDI that allows system exclusive messages. Chrome and Edge have it. Firefox needs a permission add-on, and Safari does not have it.

Preset editor

The librarian page also has an editor. Open a preset from the list or from a file, or start a new one. Every value is on a slider or a list, with a line that says what it does, on the same pages as the panel. Hear it plays the preset on the real voice. Save it as a .PRS file to copy to the card by hand, which works today with no cable at all: put it in CATHODE/PRESETS and restart.

How saving works

The aim is simple. On a healthy card, a save either completes, or the previous version stays, and the card stays readable on a computer. That is what the design aims at. It is not a guarantee, and it does not mean a card can never be corrupted.

• Starting up writes nothing, with one exception: a preset replace that a power cut stopped half way is finished at the next start, after the check below. Otherwise a card that is only played from stays as it came.
• The whole card is checked before the first write after a start. It reads every folder and file record and writes nothing. A damaged card would get more damaged by writing to it, so a damaged card is refused.
• A fault stops all writing until the next start. Reading goes on, so the music plays on.
• Every save is read back from the card before it counts.
• Projects are two files, taken in turn. A save overwrites the older one, so the one before it stays.
• Nothing is repaired or formatted by Nemesis. The one thing it clears, before the first write, is old data behind a folder's end, which no reader can see. If there is too much of it the card is refused.

Nemesis is copyright 2026 Ulf Sandfrost, and free software under the GNU General Public License, version 3 or any later version. What it is built on keeps its own licences, listed here as the project's files have them.

The sound

Plaits and stmlib, by Emilie Gillet, are part of the sound engine, under the MIT licence below.

The panel's code

The project keeps Randomwaves's MIT licence, copyright 2026 Randomwaves, for what comes from the Drumboy's stock firmware. The board's drivers come from STMicroelectronics: the STM32H7 HAL under the BSD 3-Clause licence and CMSIS under the Apache 2.0 licence. The file system is FatFs by ChaN, under its own licence.

The type

Jersey 10, the pixel face of this manual and the website, is copyright 2023 The Soft Type Project Authors. The firmware's screens use Chakra Petch, copyright 2018 The Chakra Petch Project Authors, and IBM Plex Mono, copyright 2017 IBM Corp. All three are under the SIL Open Font License 1.1.