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 Analog voices 4‑voice architecture based on Prophet‑5 Oscillators 2 analog VCOs with simultaneous waveforms Filter 4‑pole low‑pass filter with bass compensation Keyboard 37 slim keys with polyphonic aftertouch Modulation Pro‑One‑style modulation matrix Arpeggiator / Sequencer Arpeggiator with sequencer mode and glide per step Presets 128 factory presets Connectivity MIDI In/Out, USB, pedal input, line/headphone outs Construction Steel housing Dimensions 562 × 251 × 70 mm Weight 3.97 kg 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.
