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Sequential Fourm Compact Polyphonic Analog Synthesizer
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Sequential Fourm Compact Polyphonic Analog Synthesizer
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Gold Coverage goes above and beyond the manufacturer's warranty to protect your gear from unexpected breakdowns, accidental damage from handling and failures. This plan covers your product for one, two, three or up to five years from your date of purchase, costs just pennies per day and gives you a complete "no-worry" solution for protecting your investment.
Gold Coverage Includes:
- Unexpected and unintentional spills, drops and cracks
- Normal wear and tear
- Power surges
- Dust, internal heat and humidity
Other plan features include:
- For products over $200, No Lemon Policy applies. If it fails for the same defect 3 times, it is replaced on the 4th breakdown. (Does not apply to failures due to drops, spills, and cracks)
- For products under $200 experiencing the above failures, a Musician's Friend gift card will be issued for the full price of the product + tax.
- Shipping fees covered if required for repair or replacement
- Plans are transferable in the event merchandise is sold
- Plans are renewable on new gear
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Term for New Gear begins on date of purchase but does not replace the store return policy or manufacturer coverage.
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.
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: 37-note slim-key with polyphonic aftertouch
- Modulation: Pro-One style top-panel modulation matrix (no menus)
- Arpeggiator: Built-in arpeggiator with sequencer mode, glide per step
- Presets: 128 world-class factory presets
- 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 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
- Chassis: Pro-quality, all-steel chassis
- Security: Anti-theft slot
- 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)
- 12V DC Power Supply
Questions & Answers
Do you have questions about this product?
- Free Standard Ground shipping (48 contiguous states, some overweight and Used/Vintage items excluded).
- Orders placed before 3 p.m. ET usually ship the same business day.
Every guitar or bass you purchase from Musician's Friend (electric or acoustic, New or Open Box) includes two years of protection from manufacturer defects.
Our Gear Advisers are available to guide you through your entire shopping experience. Call or Chat for expert advice and to hear the latest deals.
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