Sequential Fourm 4-voice analog synthesizer

Sequential proudly unveils Fourm — a compact, expressive analog synthesizer designed to inspire. With its iconic Sequential tone, hands-on modulation, and a uniquely responsive Tactive™ keybed, Fourm is a creative partner that brings musical ideas to life.

Legendary Analog Sound, Reimagined

Built on the legendary Prophet-5 voice architecture, Fourm delivers four true analog voices with the unmistakable warmth and punch that defined a generation. Dual oscillators with simultaneous wave selection and a classic 4-pole low-pass filter (now with bass compensation) ensure that every note hits harder than the last.

A New Fourm of Expression

Fourm’s Tactive 37-note slim-key keyboard features polyphonic aftertouch, unlocking expressive techniques like guitar-style note bends, solo voice swells, and other nuanced articulations—completely transforming the experience of playing a modern Sequential polysynth.

Modulation You Can Touch

Inspired by the Pro~One, Fourm’s top-panel modulation matrix puts deep sound design at your fingertips. Route sources and destinations instantly, visualize connections with color-coded LEDs, and build complex mod paths in seconds — no menu diving, just pure creative flow.

FEATURING

• The Tactive 37-note slim-key keyboard with polyphonic aftertouch
• Warm and organic, 100% analog signal path
• Intuitive, welcoming knob-per-function layout
• Pro~One style top-panel modulation matrix
• Prophet-lineage resonant filter with bass compensation
• Arpeggiator with sequencer mode
• 128 world-class presets
• Pro-quality, all-steel chassis

SYNTHESIS

• All oscillators have simultaneously selectable waveforms – LFO too
• Oscillator B supports low frequency modes
• Classic Prophet-style Sync
• 4-Pole resonant lowpass filter
• Feedback with aggressive drive circuit
• 2 ADSR envelopes
• Sequencer supports glide per step

IN / OUT

• Main output mono (1/4” jack)
• Headphone output mono (1/4” TRS phone jack)
• MIDI in, out, and thru ports
• USB for bidirectional MIDI communication
• Footswitch/expression pedal input

POWER

• Separate power switch
• 12V DC 1.2A power supply, center-positive (included)
• Can be plugged into an AC outlet capable of supplying from 100 V to 240 V at 50 Hz/60 Hz.
• 14 Watts maximum power consumption.

PHYSICAL SPECS

• 13" L x 9.88" W x 2.75" H (56.2 cm x 25.1 cm x 7.0 cm)
• Weight: 8.76 lbs. (3.97 kg)
• Anti-theft slot