GrooveForge

GrooveForge is a small music app for MIDI keyboards and soundfonts.

It isn't a DAW and doesn't try to be one. It started as a practice companion: I wanted a portable way to relearn scales after years away from a piano, and it grew from there.

You build a rack of synths, effects and MIDI processors, stack them in whatever order you like, and save the whole setup. There's a MIDI looper with multi-track overdub, bar-accurate quantization, reverse and speed control. Jam Mode locks the keyboard to a scale, so out-of-scale notes snap to the nearest correct pitch. It's a practice aid, not a teacher.

Beyond the keyboard there's a 32-band vocoder with PSOLA pitch locking and a noise gate, a Stylophone, and a Theremin that can follow your hand through the camera if you want it to. Swipe for glissandos, or move vertically and horizontally for pitch bend and vibrato. USB and Bluetooth MIDI both work.

The microphone is used by the vocoder only, and audio is never stored or sent anywhere. The camera is used only by the Theremin's CAM mode, and no images are saved.

GrooveForge is open source under the MIT license. Built solo, with help from AI pair-programming (mostly Anthropic's Claude Code). No ads, no tracking, no accounts. Expect rough edges.

Recent changes:
Rehearsals: everyone records their part on a shared click, takes land on the beat and sync over Wi-Fi, no account
Play along to an MP3 or a video, slowed down without changing pitch
Chord chart and shared sheet music for the whole band
Autotune snaps your voice to a scale, from a gentle nudge to full robot
Direct USB output: use a USB mic and a USB DAC together
Live Input mutes itself before the phone's mic can feed back
CC mappings can now bend the pitch