Free acid toolkit for REAPER // No samples. No excuses.

The 303 invented acid.
This one is free.

A free toolkit for REAPER: the TT-303 Acid Machine synth, the TT-PHALYX drum sampler, the Theme Font Editor, the BPM2MS2HZ tempo calculator and Acid Under Control, a 24-page guide on mixing a 303 in modern techno.

Get the free guide Free // MIT-licensed tools // via ReaPack
TT-303 Acid Machine 1.07 in REAPER: synthesizer knobs, drive, delay, reverb and compressor, oscilloscope and MIDI keyboard
TT-303 ACID MACHINE v1.07 // JSFX for REAPER, 100 % modelled

Free guide

Get the guide: Acid Under Control

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What's inside the toolkit

01 // SYNTH

TT-303 Acid Machine

Monophonic acid bass synth modelled on the TB-303 circuit: 4-pole filter cascade at the original pole positions, accent network with sweep capacitor, real slide, 16-step sequencer with four banks, drive, delay, reverb and compressor. No samples, all model.

Try it in your browser → User guide (browser version) →
02 // DRUMS

TT-PHALYX Drum Sampler

16-pad drum and loop sampler: two sample slots per pad with crossfade, 64 voices, amp, filter and pitch envelopes, loop editor, 8-row modulation matrix with two LFOs, per-pad arpeggiator, scratcher and a master 4-band EQ with 12 insert effects. Pure MIDI triggering.

Reference manual →
03 // SCRIPT

TT Theme Font Editor

Point at any text in REAPER and see which theme font draws it. Make it bigger, smaller, bold or italic with a live preview, give single elements a font of their own, then bake a new theme. Your original theme stays untouched.

User manual →
04 // TOOL

BPM2MS2HZ

Note values to milliseconds and Hertz in a real tool window. Follows your project tempo, dotted and triplet values, click to copy. Your delays in sync in two seconds.

Open the browser version →
05 // GUIDE

Acid Under Control

24 pages, 11 chapters: low-end slotting, kick sidechain and groove, dynamics without killing the accents, parallel distortion, mono-safe space, automation, a signal-chain blueprint and a 10-point pre-bounce checklist.

Get it free by email →

Install in 60 seconds

  1. Install ReaPack in REAPER (one file into the UserPlugins folder, restart REAPER).
  2. Extensions → ReaPack → Import repositories, paste this URL:
    https://raw.githubusercontent.com/timtechlor/reapack-TimTechlor/main/index.xml
  3. Extensions → ReaPack → Browse packages, search for “TimTechlor”, install TT-303 Acid Machine, TT-PHALYX, TT Theme Font Editor and BPM2MS2HZ, click Apply.
  4. The Theme Font Editor also needs ReaImGui and js_ReaScriptAPI; both are in the ReaTeam Extensions repository that ReaPack ships with.