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Sequential Sequential

Sequential Fourm Compact Polyphonic Analog Synthesizer

Q&A SKU #M22794000000000
999.99 $999.99
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Overview

A 4-voice analog synth with expressive polyphonic aftertouch.

The Sequential Fourm compact polyphonic analog synthesizer delivers the soul of classic analog synthesis in a compact, hands-on unit. Built around the Prophet-5 voice structure, this synth features dual oscillators with simultaneous waveform selection and a 4-pole low-pass filter. The addition of bass compensation boosts low-end response, giving every patch more punch. Polyphonic aftertouch on the 37-note slim-key keyboard lets you bend notes or swell chords, unlocking expressive techniques not possible on most polysynths. With intuitive top-panel modulation, the unit is designed for musicians who want immediate access to sound-shaping tools—without menu-diving. Studio producers and synth enthusiasts will find this synthesizer ready for live play, sound design and hands-on experimentation straight out of the box.

Prophet-5 Voice Structure Delivers Iconic Analog Tone

The core of this synthesizer uses true analog oscillators modeled after the Prophet-5, producing a warm, organic sound. Dual oscillators offer simultaneous wave selection, while oscillator B also supports low-frequency operation for added modulation options. The 4-pole resonant filter, now enhanced with bass compensation, shapes each tone with clarity and depth. This architecture provides a punchy, dynamic response that stands out in any mix.

Polyphonic Aftertouch and Slim Keys Enable Expressive Performance

Polyphonic aftertouch across the 37 slim keys creates new opportunities for real-time musical expression. Players can bend notes, add swells or articulate each voice independently—actions usually reserved for high-end or vintage gear. This unlocks creative phrasing, making each performance more personal and detailed.

Hands-on Modulation Matrix Simplifies Sound Design

The Pro-One inspired modulation matrix sits on the top panel, using buttons and color-coded indicators for fast routing. Players select sources and destinations without scrolling through screens, visualizing complex paths instantly. This layout keeps the creative flow going, letting users experiment and build sounds quickly—crucial in both stage and studio settings.

All-Steel Chassis Provides Lasting Durability

This unit features a solid, all-steel chassis for maximum strength and longevity. High-quality knobs and switches feel precise under the fingers, while the anti-theft slot adds security for gigging musicians. Reliable construction ensures the synthesizer stands up to regular transport and long sessions, year after year.

Fourm Synthesizer Experience Rewards Creative Players

Performers and producers who value hands-on control and a classic analog signal path will connect with this synthesizer's direct interface and flexible expressiveness. The combination of polyphonic aftertouch, fast modulation routing and robust build supports musicians who want to push sound design and live performance further. Immediate access to deep features inspires new techniques and helps transform creative ideas into finished tracks.

Features

  • Warm, 100% analog signal path delivers rich and organic tones
  • Dual oscillators with simultaneous waveforms create layered and complex sounds
  • Prophet-style 4-pole resonant filter adds punch with bass compensation
  • Polyphonic aftertouch unlocks expressive techniques like bends and swells
  • Pro-One-inspired modulation matrix allows intuitive routing and sound design
  • Sequencer with glide per step creates fluid, evolving patterns
  • Feedback drive circuit adds aggressive edge for bold, dynamic tones
  • USB and MIDI ports ensure seamless integration with modern setups

Redefine your sonic palette with the Fourm polyphonic 4-voice synthesizer.

Specs

Fourm Compact Polyphonic Analog Synthesizer Specifications:

Synthesis
  • Voices: 4 genuine analog voices (based on Prophet-5 architecture)
  • Oscillators: Dual oscillators per voice with simultaneous waveform selection (Oscillator B supports low-frequency modes)
  • Filter: Classic Prophet-lineage 4-pole resonant low-pass filter with bass compensation
  • Envelopes: 2 x ADSR envelopes (authentic Prophet-5 response curves)
  • Feedback: Aggressive drive circuit
  • Oscillator Sync: Classic Prophet-style sync
  • LFO: Multi-waveform (simultaneously selectable)
Keyboard
  • Keyboard: 37-note slim-key with polyphonic aftertouch
Modulation & Controls
  • Modulation: Pro-One style top-panel modulation matrix (no menus)
  • Arpeggiator: Built-in arpeggiator with sequencer mode, glide per step
Presets
  • Presets: 128 world-class factory presets
Connectivity
  • Audio Output: 1 x 1/4" Mono (Main)
  • Headphone Output: 1 x 1/4" TRS (Mono)
  • MIDI: In, Out, Thru (5-pin DIN)
  • USB: Bidirectional MIDI communication
  • Pedal Input: Footswitch/Expression pedal input
Power
  • Power Supply: 12V DC, 1.2A (included), center-positive
  • Power Consumption: 14W maximum
  • AC Input: 100–240V, 50/60Hz (universal)
  • Power Switch: Separate on/off switch
Construction
  • Chassis: Pro-quality, all-steel chassis
  • Security: Anti-theft slot
Dimensions & Weight
  • Dimensions: 22.13" x 9.88" x 2.75" (56.2 cm x 25.1 cm x 7.0 cm)
  • Weight: 8.76 lb. (3.97 kg)
Included Accessories
  • 12V DC Power Supply
Q&A

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