From Sequential
Legendary Analog Sound, Reimagined
Fourm delivers four genuine voices of Sequential analog sound, built on the legendary Prophet-5 voice architecture—right down to its envelope response curves. With dual oscillators offering simultaneous wave selection and a classic 4-pole low-pass filter, now enhanced with bass compensation, Fourm captures the warmth and punch that shaped a generation—and takes it to the next level.
A New Fourm of Expression
Fourm’s 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 analog polysynth.
Modulation You Can Touch
Inspired by the Pro~One, Fourm’s top-panel modulation matrix puts deep sound design at your fingertips—no menu diving required. Route sources and destinations with a button press, visualize connections with color-coded indicators, and build complex modulation paths in seconds. It’s fast, intuitive, and designed to keep you in the creative flow.
FEATURING
•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
•22.13" 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
Free 3-Year Warranty
Sound Pure stands behind our products. Free three-year warranty on this item. Coverage exclusions live in Terms & Conditions, Section 27.
Level of support and expertise that simply isn't available at big-box megastores. Read the warranty →
Returns
This item is not eligible for the Try-Before-You-Buy 48-hour audition. Standard return policy applies — see Terms & Conditions, Section 18 for details.
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