Modern software programmers for vintage synthesizers with modern upgrades — standalone app and VST3 plugin for Windows.
Open the link, then click the .zip file under Assets. The installation is described in
INSTALL.txt inside the zip: copy the plugin into your VST3 folder, or start the app directly.
Nothing else to install. Windows only for now - macOS and Linux versions are planned (see
Roadmap).
| App | Synth | Upgrade | Made and tested with |
|---|---|---|---|
| SSO Kiwi-3P | Roland JX-3P | KiwiTechnics Kiwi-3P | Kiwi-3P v4.00 |
| SSO KiwiSix | Korg PolySix | KiwiTechnics KiwiSix | KiwiSix v5.00 Build 3 |
| SSO Hawk-800 | Korg Poly-800 (MK1) | HAWK-800 | HAWK-800 v2.68b |
The apps talk to the upgrade's MIDI implementation (CC and SysEx); the synth needs the upgrade. SSO Kiwi-3P is inspired by the Retroaktiv PG-2K.
- Every sound parameter on one screen, in the look of the synth, editable and automatable in the DAW - including the upgrades' extra parameters (Kiwi-3P: all 87 tone parameters with the modulation matrix; KiwiSix: 12-bit knobs; HAWK-800: all 64 original and 64 extended parameters)
- Get and send: fetch the synth's current sound, send sounds to its edit buffer; edits go out in real time; FREEZE holds them back
- Preset library with banks, categories, tags, favorites and search;
.syximport; undocumented values survive editing - Synth memory view: read all memories, store sounds by drag and drop with read-back
- Sound generator with 8 categories, KEEP masks for the sections you like, variations and history
- TEST phrase to hear the sound, All Sound Off before switching sounds
- TUNE: the synth plays an A with a plain waveform while the app plays the same tone at 440 Hz (adjustable level) - tuning an old synth by ear has never been easier; the sound comes back afterwards
- Plugin: the sound is saved with the project and sent when it opens; the track's notes are played on the synth; one instance per synth (others grey out, TAKE OVER by click)
- MIDI loop protection
- AI control (optional): AI assistants such as Claude can read and set every parameter, play notes, and use library and generator - see docs/ai-control.md
| SSO Kiwi-3P | SSO Hawk-800 |
|---|---|
 |
 |
- macOS version (VST3, AU and standalone app)
- Linux version (VST3 and standalone app)
Each app shows its version under the logo, with the synth firmware it was made and tested
with (e.g. "v1.0.0 · for HAWK-800 v2.68b"). The first two numbers are set by hand in the app's
VERSION file: the first for a complete rework, a new framework or new synth firmware, the
second for larger changes. The third counts itself: the commits that changed the app's code
(its folder, its device modules, framework/sso_core) since VERSION last changed - same
code, same number.
Problems such as a detected MIDI loop are written to %TEMP%\SSO-ownership\ownership.log.
For step-by-step details (which instance owns the synth and why), create an empty file
%TEMP%\SSO-ownership\verbose and restart the app or host.
Requires Visual Studio 2022 (C++ workload) and CMake ≥ 3.22.
git clone --recurse-submodules https://github.com/Helge666/smooth-synth-operator.git
cd smooth-synth-operator
cmake -S . -B build -G "Visual Studio 17 2022" -A x64
cmake --build build --config Release
The standalone apps end up in build\apps\<app>\<target>_artefacts\Release\Standalone. To
install the VST3 plugins, run install-vst3.ps1 from an administrator PowerShell
(powershell -ExecutionPolicy Bypass -File .\install-vst3.ps1). make-release.ps1 -Version vX.Y
packs the Release builds into the zip for a GitHub release.
| Path | Content |
|---|---|
framework/sso_core |
Device-independent JUCE module: parameter model, MIDI, controller, generic GUI, library, generator, AI control |
devices/sso_kiwitechnics |
SysEx handling shared by KiwiTechnics upgrades |
devices/sso_kiwi3p, devices/sso_kiwisix, devices/sso_hawk800 |
Device definitions and sound generators |
apps/SSO-Kiwi3P, apps/SSO-KiwiSix, apps/SSO-Hawk800 |
Standalone + VST3 plugins (device panel only; processor/editor live in sso_core/plugin) |
tests |
Unit tests and a hardware test (SSO_Tests --hardware "<port name part>") |
docs |
Measured MIDI behaviour of the Kiwi-3P, the KiwiSix and the HAWK-800, AI control guide |
AGPLv3 (JUCE is used under its AGPLv3 option) - see LICENSE.
Roland, JX-3P, Korg, PolySix and Poly-800 are trademarks of their respective owners. Kiwi-3P and KiwiSix are upgrades by KiwiTechnics, HAWK-800 is an upgrade for the Poly-800 by its own developers. This project is independent and not affiliated with any of them.