303 Note - Acid Sequencer
tb-303 sheets
About
Quickly create, manage, and play back acid bassline synth sequences. Features a step sequencer, built-in synth knobs for tone shaping, and CSV export for backups. Ideal for musicians needing to save and recall patterns.
What's New in 303 Note
2.1.1
July 19, 2026
Bug fixes: ・Fixed an issue where the first playback after launching the app could produce no sound. ・Fixed an issue where adjusting the sound knobs could unintentionally move the screen.
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FAQ
What is 303 Note used for?
303 Note is an application designed for quickly jotting down, managing, and playing back acid bassline synth sequences, inspired by the TB-303 synthesizer. It allows users to save patterns and adjust the sound using built-in synth knobs.
Does 303 Note have ads?
No, 303 Note does not contain advertisements. It is a completely free application with no ads to interrupt your creative process.
How does 303 Note's sequencer work?
The app features a dedicated step sequencer screen that mimics the feel of the original hardware. Users can edit Note, Down/Up, Accent, and Slide parameters directly on this screen.
Can I export my patterns from 303 Note?
Yes, 303 Note supports CSV export for your saved patterns. This feature allows for easy backup and management of your sequences on a computer.
What kind of tone controls does 303 Note offer?
303 Note includes TB-303-style tone knobs for shaping your basslines. You can adjust CUTOFF, RESO, ENV, DECAY, and ACCENT to dial in the desired squelchy sound before committing patterns.
Is 303 Note available on multiple devices?
Currently, 303 Note is supported on iPhone devices. Information regarding availability on other platforms like Android or tablets is not provided.
How often is 303 Note updated?
The latest version of 303 Note is 2.0.0, which was last updated on July 5, 2026. This indicates a recent update, suggesting ongoing development and support.
What is the age rating for 303 Note?
303 Note has an age rating of 4+. This means it is suitable for users aged four and older, indicating no mature content.