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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.
| Product Name | Sequential Fourm 37-Key 4 Voice Analog Synthesizer w/ Polyphonic Aftertouch |
|---|---|
| Brand | Sequential |
| Condition | New |
| MPN | SEQ-3900 |
| UPC | 855346000487 |
| Shipping Option | Free Shipping to the Continental U.S. |
What's in the Box?
- Sequential Fourm 37-Key 4 Voice Analog Synthesizer w/ Polyphonic Aftertouch
- 2V DC 1.2A Power Supply
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 | Bidirectional MIDI communication |
| Footswitch/Expression Pedal Input | Yes |
Power |
|
| Power Switch | Separate power switch |
| Power Supply | 12V DC 1.2A, center-positive (included) |
| AC Compatibility | 100 V to 240 V at 50 Hz/60 Hz |
| Maximum Power Consumption | 14 Watts |
Physical Specs |
|
| Dimensions | 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 | Yes |
Sequential Fourm 37-Key 4 Voice Analog Synthesizer w/ Polyphonic Aftertouch
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.
| Product Name | Sequential Fourm 37-Key 4 Voice Analog Synthesizer w/ Polyphonic Aftertouch |
|---|---|
| Brand | Sequential |
| Condition | New |
| MPN | SEQ-3900 |
| UPC | 855346000487 |
| Shipping Option | Free Shipping to the Continental U.S. |
What's in the Box?
- Sequential Fourm 37-Key 4 Voice Analog Synthesizer w/ Polyphonic Aftertouch
- 2V DC 1.2A Power Supply
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 | Bidirectional MIDI communication |
| Footswitch/Expression Pedal Input | Yes |
Power |
|
| Power Switch | Separate power switch |
| Power Supply | 12V DC 1.2A, center-positive (included) |
| AC Compatibility | 100 V to 240 V at 50 Hz/60 Hz |
| Maximum Power Consumption | 14 Watts |
Physical Specs |
|
| Dimensions | 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 | Yes |
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