Pattern303: Your TD‑3‑MO Patterns, On Screen.
An unofficial pattern editor and librarian for the Behringer TD-3-MO. Write and tweak acid lines on a clear, visual grid, keep every pattern organised and backed up, and hear your ideas instantly with the built-in synth and kick — even when the hardware isn't connected.
Free 7-day trial · fully functional · no credit card · macOS | Explore features ↓
Everything Your Patterns Need
Visual Pattern Editor
See the whole pattern at once. Set notes, octaves, accents, slides and rests step by step on a clear grid — no more programming blind from the front panel.
Pattern Librarian
Pull patterns from your TD-3-MO, name and organise them, and send them back whenever you need them. Build a library of your best lines and never lose a pattern again.
Real-Time Preview
A built-in synth and kick let you hear every edit as you make it. Audition patterns on the train, in the hotel or anywhere the hardware isn't — then send them to the TD-3-MO when you're back.
From Hardware To Screen And Back.
Pattern303 sits between you and your TD-3-MO. Bring your patterns in, shape them on screen where you can actually see what you're doing, and audition them instantly with the built-in sounds.
When a line is right, send it back to the hardware — or file it away in your library for the next session.
- Connect your TD-3-MO and load its patterns
- Edit and preview with the built-in synth and kick
- Send patterns back, or save them to your library
Made For The TD-3-MO.
Native support for Apple Silicon and Intel Macs.
Works with any DAW that supports AU or VST3. Pattern303 is an independent, unofficial tool and is not affiliated with Behringer or Music Tribe.
Built By a Musician, For Musicians
Programming a 303-style sequencer from the front panel is part of the charm — until you want to see the whole line, fix one slide, or find that pattern you wrote last month. Pattern303 handles the bookkeeping so you can stay focused on the groove.
I'm Ajja — musician since age nine, self-taught coder since the early 90s, and recording and worldwide touring artist for over 20 years. Pattern303 joins Interlock in the growing family of tools from Ajja Sonic.
Read the full storyTD-3-MO Editor: Questions & Answers
What is Pattern303?
Pattern303 is an unofficial pattern editor and librarian for the Behringer TD-3-MO. It runs as an AU or VST3 plugin in your DAW and lets you see, edit, organise and back up your TD-3-MO patterns on your computer.
Can I edit my TD-3-MO patterns on the computer?
Yes. Load the patterns from your TD-3-MO, then set notes, octaves, accents, slides and rests step by step on a clear grid, and send the result back to the hardware.
Can I back up and organise my TD-3-MO patterns?
Yes. The librarian pulls patterns from the TD-3-MO so you can name them, organise them and keep a library of your best lines, then send any of them back whenever you need it.
Do I need the TD-3-MO connected?
Only to load patterns from it and send them back. Editing and listening work anywhere: the built-in synth and kick play your patterns in real time without the hardware.
Which computers and DAWs does it work with?
Pattern303 runs on macOS, on Apple Silicon and Intel Macs. A Windows version isn't available yet. It works in any DAW that supports AU or VST3 plugins, such as Ableton Live, Logic Pro, Bitwig Studio, Cubase, Reaper or Studio One.
Is there a free trial?
Yes. The 7-day trial is fully functional and needs no credit card.
Is Pattern303 made by Behringer?
No. Pattern303 is an independent tool made by Ajja Sonic and is not affiliated with Behringer or Music Tribe. TD-3-MO is a trademark of its owner.
Ready to write some acid?
Trial is fully functional for 7 days. No credit card required.