Three legends in the circuit

The BS-203 is a faithfully analog-modeled acid synthesizer, built at component level on two early-'80s Japanese bassline computers - the silver companion sequencer of 1983 and the little acid box of 1982 whose model numbers ours politely tips its hat to - plus the modern Juteon Bassboy, which is an homage to the original Acid machine with some extra nastiness added.

MODE 303Classic

The acid squelch you desire

MODE 202Silver

Steeper envelope, brighter top end.

MODE BBバスビッチ

A freaky take on the classic

Finishes aren't just paint - each mode re-plumbs the mixer and filter sections. Switch instantly, keep your pattern.

The Acid Brain · pattern-generating sequencer

A one-of-a-kind generator that composes acid lines locked to harmonic major or minor scales - then hands you granular control over every dimension of the line:

• MODE · NOTES · LENGTH - personality, density, phrase size
• GATE · DIV · ACCENT · SLIDE - articulation and 303-ness per square inch
• KEY + Maj/Min - everything generated fits your track
• RANDOMIZE - a new idea on every press · GRAB MIDI drags the keepers into your DAW

Effects with studio provenance

The onboard FX rack - SATCH saturation, tempo-synced delay, and reverb - is modeled after the classic units racked in the Born Second studio: the boxes we reach for when need to finish a bassline. Characterful, musical, and engineered to stay out of the sub's way.