Back in 1970, this duo hit the scene as one of the earliest portable sequencer-synth combos, predating many iconic setups and packing innovative tricks like a built-in voltage quantizer that snaps steps to perfect musical notes without endless tweaking.
The 400 sequencer pairs with the 401 sound module for a semi-modular desktop system, featuring two VCOs with saw, square, and noise waveforms, plus a flexible 2-pole filter handling low-pass, high-pass, and band-pass modes with resonance. It boasts dual 16-step fader rows—run them parallel for two sequences, series for 32 steps, or mix lengths—with top rows for tempo/envelope control, middle for quantized pitch CV, and bottom for gated pulses to trigger external gear. The 401 adds voltage-controlled attack/release on its AR envelope, six LFOs for wild modulation, CV/gate ports for modular integration, and a stereo audio out, all in a compact, silver-faced unit that's monophonic but endlessly experimental.
Over decades, players cherish its raw, gritty tones for basslines, leads, and FX, calling it a 70s workstation that stands alone or drives Moogs and ARPs—though those vintage sliders can get crackly with age, adding character if you're into that lived-in vibe.[web:1][web:2][web:3][web:4][web:5]
