After a first outing at Superbooth as a hand-built prototype, Twisted Electrons’ FLEXFM is getting serious: the spec sheet is final, pre-orders are open and the French maker is aiming to ship before the end of the year. The name hides an eight-voice hybrid groovebox that refuses to choose between FM synthesis, sampling and analog filtering. In short, a machine that wants to cram a sound-design studio into a stage-ready box.
Eight voices, one per track, and generous FM
The FLEXFM lines up eight voices, each driven by its own sequencer track. The sound engine is built on four-operator FM, but Twisted Electrons didn’t stop at the usual sine waves: each operator can pull from a wide set of engines — classic waveforms, wavetables, macro oscillators, 8-bit-flavoured textures, hand-drawn waveshapes and, crucially, sample playback. Operators combine through a matrix that allows FM, ring modulation, AM and oscillator sync, all morphable in real time with the joystick.
That blend of FM and sampling is the machine’s real signature. You can sample straight through the line input, import WAV files, then treat those samples like any other operator: slicing, resampling, repitching. In practice, that lets you start from a metallic FM pad and drop in a resampled drum loop without ever leaving the instrument.
An analog filter per voice, digital filters on top
Every voice gets a multimode analog filter offering fifteen responses from pole mixing — low-pass, high-pass, band-pass and notch — with cutoff and resonance under your fingers. That’s what gives the FLEXFM its warmth, where many FM grooveboxes stay stuck in the digital domain. On top, Twisted Electrons adds three digital filters with strong characters: a crisp one, a Z-plane-inspired morph and a third that roams a space of peaks and notches. Each carries its own ADSR envelope, velocity response and key tracking.
Add four LFOs per voice — each with its own waveforms, an ADSR mode or a joystick-drawn curve, destination, sync and loop options — and this is clearly no toy. The modulation depth is that of a full-blown synth, multiplied by eight.
A sequencer built to play, not just to program
The sequencer offers one lane per voice, up to 128 steps and sixteen patterns. Each step takes its own length, parameter locks, conditions, timing shifts and trigger probability. Twisted Electrons grafts on per-step operator masking — a rare idea that evolves the timbre across the sequence — along with an arpeggiator, swing, sub-steps and drills. The “tempoFlex” curve lets you speed up, slow down or pull against the master clock, and the X/Y pad morphs patterns live through several algorithms.
For playing, a velocity-sensitive piezo pad and a polyphonic mode allowing four notes per voice round out mono, chord and sync modes. Three in-house effects close the chain: a plate reverb with pitch-shifted shimmer, a vintage feedback echo and a sidechain-pumping compressor.
Connectivity and price
The rear confirms the machine’s stage ambitions: an individual 6.3 mm output for each voice, a main stereo output, a headphone socket, a mono input for sampling, MIDI in and out, and a USB port handling both data and multitrack audio streaming. A full software editor ships alongside to manage and sculpt sounds from the computer.
| Spec | FLEXFM |
|---|---|
| Voices | 8 (one per track) |
| Engine | 4-operator FM + sample playback, many operator engines |
| Filters | 1 multimode analog (15 responses) + 3 digital filters per voice |
| Sequencer | 128 steps, 16 patterns, parameter locks, probability, operator masking |
| Outputs | 8 individual outs, stereo, headphones, multitrack USB audio |
| Price | 999 euros pre-order (offer until 13 November 2026) |
The FLEXFM succeeds the TwistFM, keeping its analog filter type while adding sampling and resampling. Pre-orders are open at an introductory 999 euros including VAT, with shipping estimated before Christmas 2026 — an estimate, the maker warns, not a fixed date. To understand what frequency-modulation synthesis actually involves, our FM synthesis guide breaks down operators and algorithms. Twisted Electrons had already explored FM in plugin form with the vMEGAfm, and anyone familiar with its sequencers will recognise the logic covered in our step sequencing explainer. The full spec sheet is on the maker’s product page.
My take
The FLEXFM ticks the box FM grooveboxes kept missing: a real analog filter per voice, not an emulator bolted on at the end of the chain. That’s the difference between a machine that sounds cold and one you actually want to push. Twisted Electrons’ bet — eight voices, FM plus sampling, a deep sequencer and joystick performance — clearly targets people who want to build a whole track without a computer. The sticking point is the price: at 999 euros this is no impulse buy, and the “before Christmas” promise asks for a little faith. If the thing delivers sonically, it has what it takes to anchor a setup.
