The Essentials to Know About the Sequential Fourm Synthesizer
- True 4-voice analog inspired by the legendary "Prophet-5" with a 4-pole low-pass filter and bass compensation.
- Expressive playability thanks to the slim 37-key keyboard featuring polyphonic aftertouch.
- Immediate sound creation via the front panel modulation matrix, inherited from the "Pro-One" spirit.
- Ready for stage and studio: arpeggiator with sequencer mode, 128 presets, and steel chassis.
A Compact Heir to the Prophet Lineage
Fourm adopts the sound architecture and envelope curves that made the Prophet series famous, in a portable format designed for modern musicians. Its fully analog signal path and resonant filter deliver that punchy and warm character that has defined generations, while adding bass compensation to preserve the low-end foundation at high resonance.
Who Is It For and What Are Its Uses?
Ideal for keyboardists and producers seeking a
versatile and expressive analog synth. Perfect for live performance and studio work in electro, techno, synthwave, pop, ambient, or sound design for visuals. Motivated beginners will appreciate the "one function per control" layout, while advanced users will exploit the polyphonic aftertouch and advanced modulation options for nuanced performances.
Features and Innovations
Fourm employs subtractive synthesis with two oscillators per voice, capable of
simultaneously selecting waveforms to enrich harmony and attack. Oscillator B can transform into an LFO for deep modulations, and the
front panel matrix allows routing sources and destinations in one gesture, with color-coded indicators to visualize your patches. The
4-pole low-pass filter and feedback/drive circuit add character, while two ADSR envelopes precisely sculpt the timbre. On the playability side, the arpeggiator with sequencer mode, step glide, and polyphonic aftertouch open the door to expressive articulations (bends, swells, dynamic nuances). MIDI DIN/USB connectivity ensures smooth integration into any setup, and the
128 presets provide an immediately usable sound palette.
Technical Specifications
FEATURES
- Slim 37-key keyboard with polyphonic aftertouch
- Fully analog signal path with warm, organic sound
- Intuitive layout with one function per control
- Front panel modulation matrix inspired by the Pro-One
- Resonant filter in the Prophet tradition, with bass compensation
- Arpeggiator with Sequencer Mode
- 128 sophisticated presets
- High-quality all-steel chassis
SYNTHESIS
- All oscillators and LFOs allow simultaneous waveform selection
- Oscillator B also serves as an LFO
- Classic synchronization, as on the Prophet
- 4-pole resonant low-pass filter
- Feedback with aggressive drive circuit
- 2 ADSR envelopes
- Step glide for the sequencer
CONNECTIVITY
- Main mono input (6.35 mm jack)
- Mono headphone output (6.35 mm TRS jack)
- MIDI input, output, and Thru
- Bidirectional USB MIDI port
- Input for expression pedal/footswitch
POWER SUPPLY
- Separate power on/off switch
- 12 V DC, 1.2 A center-positive power supply included
- Can be connected to an AC outlet providing 100 V to 240 V at 50 Hz/60 Hz
- Maximum power consumption of 14 watts
DIMENSIONS AND WEIGHT
- 562 mm W x 251 mm D x 70 mm H (22.13" x 9.88" x 2.75")
- Weight: 3.97 kg (8.76 lbs)
- Kensington lock compatible
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