Sequential Fourm is a compact analog synthesizer that invites you to play, shape and perform with unprecedented expression. With its legendary Sequential tone, hands-on modulation and uniquely responsive keybed, Fourm is a creative partner helping to bring your musical ideas to life.
- 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
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 SCI 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.
| Specification | Value |
|---|---|
| SKU | SEQ-FOURMCBK |
| Model Name | Fourm |
| Vendor | Sequential |
| Aftertouch | Yes |
| Analog Digital | Analog |
| Built In Speakers | No |
| Included From Manufacturer | Power supply |
| Keys Weighted | No |
| Number of Keys | 37 |
| Key Size | Slim Keys |
| Midi | In, Out, Thru, and USB |
| Mono Poly | Polyphonic |
| MPN | SEQ-3900 |
| Product Unique Features |
|
| Key Action | Tactive synth action keybed with polyphonic aftertouch |
| Number of Patches/Programs |
512 program locations 120 factory presets |
| Voices of Polyphony | 4 |
| Oscillators per Voice | 2 |
| Sequencer | Arpeggiator includes sequencer mode |
| Arpeggiator | Yes |
| USB Port (to Host) | MIDI |
| Audio Outputs |
1/4" main output 1/4" headphone output |
| Control Connections | 1/4" footswitch or expression pedal input |
| Onboard Controllers |
Pitch bend wheel Mod wheel |
| Width | 22.13" |
| Depth | 9.88" |
| Height | 2.75" |
| Product Weight | 8.76 lb |
Sequential warrants that its products will be free from defects in materials and/or workmanship for one (1) year from the date of purchase. Please register your product online at at the Sequential website to establish the date of purchase. This is not a requirement for warranty service, but it will help expedite the warranty service process. See Sequential's website for more details.
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