Ammonite-Seed

A three-voice arpeggiator synthesizer on the Daisy Seed
12 knobs · a round screen that draws the music · chords, polyrhythms and echoes in one small box

▶ Listen: two minutes of Ammonite-Seed
Watch the screen play (video with sound) · Owner's manual (PDF) · VST3 / CLAP plugin

Part of the Ammonite family: Ammonite-Seed (this one) · Ammonite Desktop (Windows VST3 / CLAP / standalone) · Ammonite Mini (Android tablet)

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Ammonite-Seed is three monophonic synth voices, each with its own arpeggiator, envelopes, filter, five LFOs and stereo echo, all locked to one master clock and one key. You never pick notes: you pick a key, a chord progression and, for each voice, which notes of the chord it may play and in what rhythm. Everything it plays is in key, and the three patterns can run at different lengths and speeds without ever drifting apart.

The round screen shows the three arps as rings: each ring is that voice's real waveform, cut into its steps, with every note in its own color (the colors follow the circle of fifths, so a chord has a look as well as a sound).

• Three voices, each two detuned oscillators morphing sine / square / saw
• Three arpeggiators: 6 modes, 5 note pools, 1-3 octaves, 9 divisions incl. triplets, 1-16 step patterns, Euclidean density, random note variation, ratchets
• Harmony: 10 scales and 10 chord keys, 8 chord progressions, manual chords
• Per voice: amp, filter and pitch envelopes, glide, a morphing LP/BP/HP filter, 15 LFOs in all (pitch, cutoff, amp, pan, shape), a tempo-synced stereo delay
• Shared: drive, reverb, swing, four screen views
• No menus: nine pages of knobs, one column per voice

Listen

▶ Two minutes of Ammonite-Seed

That and every clip below play in your browser on the listening page. The recipes are rendered straight from the synth engine, 40 seconds each; every one is in the owner's manual, so you can dial it in yourself.

Power-on	what Ammonite-Seed plays the moment it has power: three arps in A minor
Slow tide	three drones sliding through a progression under a breathing filter
Clockwork	sixteenth-note patterns of 8, 7 and 5 steps turning against each other
Dub echoes	a sparse chord stab into a dark, wobbly ping-pong echo over a sine bass
Late set	a swung ii-V-I in C with a gliding bass
Bells in D	Pachelbel's chords played by pitch-swept sine bells

The screen

Turn a knob and the screen shows what it is and its value; turn the page knob and it shows what every knob on the new page does:

Hardware

The front panel, assembled and playing.

The printed enclosure, version 1.

Version 1 of the hardware is simple, and meant to be built with a soldering iron and a breadboard:

• an Electrosmith Daisy Seed3
• a GC9A01 1.28" round 240x240 display, 7-pin SPI module
• 12 x WH148 B10K linear potentiometers (15 mm shaft) with knobs
• a 3.5 mm stereo jack for the output, a breadboard and jumper wire
• a 3D-printed enclosure: six parts in hardware/stl
• USB-C for power and flashing

The wiring is in hardware/wiring. A full hardware manual (parts, printing, assembly, wiring, flashing) is on the to-do list; the enclosure will keep changing (side panels, a proper home for the jack), so treat this as version 1.

Getting started

Flash the firmware

1. Download ammonite.bin from the Ammonite-Seed 0.2.0 release.
2. Put the Seed in bootloader mode: hold BOOT, tap RESET, release BOOT.
3. Open the Daisy Web Programmer in Chrome or Edge, connect, choose the file and flash.

Build from source (Windows)

You need the Daisy toolchain and Git for Windows. In PowerShell:

git clone --recursive https://github.com/GSNautilus/ammonite
cd ammonite
.\ammonite.ps1 libs     # once: builds libDaisy and DaisySP
.\ammonite.ps1 build    # firmware\build\ammonite.bin
.\ammonite.ps1 flash    # build and flash over USB (bootloader mode first)

Try it without hardware

The PC simulator runs the exact same engine and draws the exact same screen, with the panel's twelve knobs under your mouse. It needs Python 3.11 with the packages in requirements.txt:

pip install -r requirements.txt
.\simulator.bat

(If the right python is not on your PATH, set AMMONITE_PYTHON to its python.exe.) .\ammonite.ps1 test runs the engine's 193 headless checks.

Play it in a DAW (VST3 / CLAP, Windows)

Ammonite-Seed is also a plugin for Windows DAWs, with the same engine, panel and screen as the hardware (its copy of the engine is checked bit for bit against the firmware's). It is the Seed in a DAW, not Ammonite Desktop, which is a separate, bigger instrument.

1. Download Ammonite-0.2.0-win64.zip from the Ammonite-Seed 0.2.0 release and unzip it.
2. Copy the Ammonite.vst3 folder into C:\Program Files\Common Files\VST3, and/or Ammonite.clap into C:\Program Files\Common Files\CLAP.
3. Rescan plugins in your DAW and load Ammonite on an instrument track.

It plays by itself as soon as it is loaded. SYNC DAW (the default) follows the DAW's tempo and bars: patterns and chord progressions line up with the song and follow the playhead; SYNC FREE runs on its own TEMPO knob like the hardware. Every knob of every page is an automatable parameter, saved with the project; turning a knob on the panel records automation. Any sample rate from 44.1 to 192 kHz.

Tested in FL Studio 2025. Good to know: Ammonite's bars are always 4/4, and it ignores MIDI notes, so a DAW's channel mute (which mutes by holding back notes) does not silence it: mute or turn down its mixer track instead.

To build it yourself you need the Visual Studio 2022 Build Tools (the C++ workload, with CMake). In PowerShell, from the repository:

.\plugin\plugin.ps1 build     # plugin\build\cmake\bin\Ammonite.vst3 and Ammonite.clap
.\plugin\plugin.ps1 install   # copies both into the system plugin folders (run as administrator)
.\plugin\plugin.ps1 test      # the engine and plugin tests

To do

• Hardware manual: parts list, printing, assembly, wiring and flashing, with photos of the build
• Enclosure v2: back and side panels with room for the jack and USB
• Measure CPU load on the Seed with every effect running
• VST3 / CLAP plugin for Windows, synced to the DAW's tempo (0.2.0)

Repository

Folder
core/	the synth engine: portable C++14, no hardware code. Everything musical lives here
firmware/	the thin Daisy shell: knobs in, audio and screen out
sim/	the PC simulator (Python + the engine as a DLL)
tests/	headless tests that play the engine and measure what comes out
plugin/	the VST3 / CLAP plugin (DPF): its copy of the engine, the panel UI, its tests
manual/	the owner's manual: its screen captures are made by driving the engine
hardware/	enclosure STLs and wiring diagrams
media/	everything on this page, rendered by media/make_media.py
lib/	libDaisy and DaisySP (git submodules; plugin/lib/DPF for the plugin)

License

Ammonite is released under the MIT license.

It builds on Electrosmith's libDaisy and DaisySP (MIT). The reverb, ReverbSc, comes from DaisySP-LGPL and is licensed under the LGPL-2.1; it is linked into the firmware and the simulator, and its full source is included here as a submodule. The plugin links its own copy of it (plugin/engine, with a larger buffer for high sample rates, source included) and is built with the DISTRHO Plugin Framework (ISC).