Good Fourm from Sequential

Sequential has announced the release of its most affordable, synthesizer to date. Fourm is a compact, 100% analogue instrument that redefines expressive electronic performance. With its warm, organic tone, hands-on modulation routing, and a uniquely responsive polyphonic aftertouch keyboard, Fourm is ready to bring your musical ideas to life.

At its core, Fourm delivers four analogue voices of genuine Sequential sound, derived from the legendary Prophet-5 — complete with dual oscillators, a classic 4-pole lowpass filter, and envelope curves modeled after the 1978 original. The result is unmistakable Sequential warmth and punch, now with overdriven feedback for a performance-ready edge.

For the first time in 40 years, Sequential has returned to polyphonic aftertouch. The team developed the new Tactive slim-keys poly AT keybed to work in concert with Fourm’s analogue synthesis engine. Every element was co-designed and precisely calibrated to unlock new levels of expression, enabling a deeper connection to our signature sound that no off-the-shelf keybed could deliver. The result is a more expressive bond between player and instrument, energizing new modes of creativity.

“Wowww holy smokes, this thing sounds and feels amazing,” said Bryn Bliska, (keyboards for Chappell Roan, Maggie Rogers, Jacob Collier). “The polyphonic aftertouch is seriously so fun… Sequential nailed it.”

“We’re so excited to bring this innovative all-analogue keyboard into the world,” said David Gibbons, Sequential CEO. “At a price-point that most people expect to pay for a monophonic synth, we think this product will invite legions of musicians who have longed for the magic of polyphonic analogue sounds to start their journey of discovery with Sequential.”

Notably inspired by the Pro-One, Fourm’s top-panel modulation matrix puts deep sound design at your fingertips—no menu diving required. Modulation sources and destinations are clearly labeled, connections are made with a button press, and colour-coded indicators make even complex routings easy to manage.

With its compact footprint, professional-grade build, and a sound engine rooted in Sequential’s most iconic instruments, Fourm is a powerful new voice in analogue synthesis.