Lemus ro-mono-303 v0.1.3 beta STANDALONE VST3 AU WiN MAC + ROM Firmware

ro-mono-303 is a free emulation of the classic Roland TB-303 Bass Line, the monophonic bass synth and step sequencer that shaped acid house and electronic music. This plugin doesn’t just approximate the sound; it runs the original sequencer firmware on an emulated CPU and models the voice circuit part by part based on the service notes. Without the ROM image (d650c-133.ic8, not included), it operates in voice mode, letting you play the iconic bass sounds via MIDI without the internal sequencer. The developer measured it note by note against 400 notes recorded from a real TB-303, so you get authentic character and response. It’s available as a standalone application and in VST3 and AU formats for Windows and macOS. Whether you’re a hobby producer crafting acid basslines in FL Studio, Ableton, or Logic, or a sound designer looking for that unmistakable 303 grit, ro-mono-303 delivers the goods for free. Just bring your own ROM if you want the full sequencer experience.