The Fourm is Sequential’s compact 4‑voice analog synthesizer built on the iconic Prophet‑5 voice architecture. It delivers rich dual‑oscillator tone, a classic 4‑pole low‑pass filter with bass compensation, and a highly expressive polyphonic aftertouch keybed. Designed for hands‑on sound shaping and performance, it offers deep modulation, an arpeggiator, a sequencer, and a responsive Tactive™ keybed that encourages dynamic, nuanced playing. With its modern analog circuitry and performance‑ready layout, it serves as a powerful creative instrument for studio musicians and live performers alike.

Key features

Included Accessories

• External power supply

Included Software

• Factory pre-set library (128 sounds)

Overview

The Fourm combines classic Sequential analog tone with modern expressive control. Its dual‑oscillator engine, Prophet‑style filter, and responsive aftertouch keybed provide a wide sonic palette—from warm pads and punchy basses to evolving textures and expressive leads. With hands‑on modulation, a built‑in sequencer, and robust connectivity, it is designed as a versatile centerpiece for both hardware‑focused and hybrid studio setups.