Web Tracks

An unofficial, fan-made browser groovebox inspired by the Novation Circuit Tracks — 8 tracks, a 4×8 pad grid and a Web Audio synth engine, no install.

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Visit site → Source code →

A tribute to the Novation Circuit Tracks, rebuilt as something you can open in a browser tab. Web Tracks recreates the hardware groovebox — 8 tracks, a 4×8 pad grid, the step sequencer and its whole view system — as a single static page with an original Web Audio synth engine. No install, no account, no backend: open the URL and press play.

The first version came together in a single day with Claude’s Fable model — that story is in Cloning My Circuit Tracks in a Fable Day.

What it does

  • 8 tracks — 2 synth, 2 MIDI and 4 drum — sequenced on a 4×8 pad grid
  • The hardware’s view system — Note, Velocity, Gate, Probability, Micro Step, Pattern Settings, Patterns, Mixer, FX, Side Chain and Scales
  • An original Web Audio synth engine — 6 voices per synth to match the device, plus filters, envelopes, 8 macro knobs, reverb and delay
  • 64 project slots — while playing, switching is queued to the end of the current pattern, exactly like the hardware
  • The real file formats — imports and exports .ncs projects, .syx patches and .circuittrackspack packs, so projects can move between the browser, Novation Components and an actual device
  • Session persistence — the workspace autosaves to IndexedDB, so an accidental reload doesn’t cost you the jam
  • A starter pack generated from code — 64 drum samples, 128 synth patches and 16 demo projects, all synthesized by a script rather than sampled

Playing it

Hit Space to start and press Projects to load one of the demos. The pads play notes or program steps depending on which track and view you’re in, and the eight macro knobs shape the active sound. Everything runs locally — drop a .ncs project or a pack anywhere on the page and it loads in the browser; nothing is ever uploaded.

Not affiliated with Novation

Web Tracks is a non-commercial fan project. It is not affiliated with, endorsed or sponsored by Novation or Focusrite plc, and “Circuit Tracks” is a trademark of its owner. The project and pack formats were independently reverse-engineered by observing the files the hardware and Components produce — no Novation source code, firmware or proprietary documentation was involved — and the synth engine is an original implementation that shares no code with the device. Every bundled sound, patch and project is generated from code, so nothing here is copied from factory content.

  • circuit-tracks-tools — the Python library and MCP server that drives the real hardware over MIDI, and where the format reverse-engineering started