Janus — Dual-Engine Synthesiser Voice for Eurorack

Launch price — £219. Janus is hand-built here in the UK in small batches, and the first 25 go out at £219 as a thank-you to anyone coming along early. After that the price settles at £239.

Janus is not an oscillator. It's a complete synthesiser — two independent engines, twelve kinds of synthesis, a chord engine, a polyphonic arpeggiator, a modulation matrix, preset memory and a full stereo effects chain — all played from one CV and gate.

One pitch CV and one gate go in. What comes out is a part: voiced, played, effected and finished.

Full user manual: Download Janus Dual-Engine Synthesizer Voice for Eurorack

Two engines, twelve kinds of synthesis

Two engines run at once, independently, each with eight voices and its own filter, envelopes, level and tuning. Set each to whichever synthesis suits the sound:

V-Analogue — two oscillators with sync, sub and unison 
FM — six-operator, DX-style, with the full bank 
Modal — struck, plucked and bowed resonant bodies 
String — Karplus–Strong plucks, bows and blows 
Drums — nine tuned drum voices 
Tonewheel — a nine-drawbar organ with percussion 
Wavetable — morphing wavetables with a position LFO 
Phase Dist — CZ-style phase distortion 
Additive — partials, tilt, odd/even and comb 
Formant — vowel and voice synthesis 
Waves — the four classic shapes, done properly 
Noise — white and pink through the engine filter

Engine 1 can cross-modulate engine 2 by FM or AM, tapped before its level — so an engine set silent is still a full-scale modulator.

And every engine is loudness-matched to every other by measurement. Switching type is a musical decision again, not a trip to the output knob.

One gate, a whole part

Janus takes a single pitch CV and gate. It holds eight voices inside, but they are not eight keys — they are what lets a note ring on past the gate, what the chord engine stacks a single trigger into, and what the arpeggiator spreads across time.

The chord engine turns one gate into a voicing — including just-intonation and harmonic stacks — and can advance the chord type on every note, so a plain sequencer track walks a progression. The arpeggiator then takes whatever is held and spreads it, with harmony, strum, pedal-point, ratchets and generative variation. And on the struck engines, notes decay naturally long after the gate has closed.

One sequencer track in. A moving polyphonic part out.

Two knobs that are always the right two

Janus boots into its PLAY screen, and that is where it is meant to live.

Two knobs sit on the sound in front of you, already mapped to the controls that define whichever engine you are on — a wavetable's scan, a modal body's material and strike, an organ's drawbars, an FM voice and its brightness. Nothing to bind, nothing to set up, nothing to remember. A click swaps them to the page's other two parameters.

Eight pages carry the rest under the same two knobs: levels, both envelopes, the filter, the effects, the granular section and the engine's pitch placement. The depth is all still there — the matrix, the operator envelopes, the mode tunings — but it sits behind the instrument rather than in front of it.

A studio on board

A full stereo effects chain, all of it on the module: Age for the drift and wear of a well-used instrument, then bitcrusher, filter and drive, phaser, granular, delay, reverb, chorus and glitch. Every effect has its own wet and dry, and every parameter is a modulation destination.

The granular engine

The granular section is the one to go and find first.

It sits in the middle of the chain, after the filter and phaser and before the delay and reverb — so it granulates the whole instrument, both engines together, and the grains then land inside the delay and the reverb rather than being sprinkled over the top of them. Audio runs continuously into a capture buffer, and grains are read back out of it with Hermite interpolation, up to eight overlapping at once.

• Position — where in the buffer the grains are read from: hard right is the audio you just played, hard left is the oldest still held.
• Size and Density — from single isolated grains drifting past with silence between them, to a solid cloud.
• Pitch — ±2 octaves, and Jitter scatters it per grain, so one setting gives a chorus of pitches rather than a transposition.
• Spray — scatters where each grain starts reading, smearing a tight loop into a wash.
• Texture — opens the grain window from a soft Hann curve towards a near-boxcar, which is the difference between a breath and a stutter.
• Random — moves the spawn clock from strictly periodic to Poisson, so the cloud stops sounding machine-timed.
• Grain arpeggio — steps each successive grain up or down by up to an octave over a settable number of steps, turning a held buffer into a figure.
• Freeze — stops the capture. What is in the buffer stays there, and everything above keeps working on it, indefinitely. Play on top of it with the instrument it came out of.
• Fine and Long modes — a short buffer with full bandwidth for stutters and glitches, or a four-times-longer one for pads and drones.

Four of these sit on the knobs on PLAY's own Granular page, and every single parameter is a modulation destination — so Position can be swept by an envelope, Freeze triggered from a gate, Density tracked from a CV input.

Modulation and memory

Four mod sources — LFOs, sample-and-hold, random, envelopes, probabilistic gates and Euclidean patterns — plus two mod envelopes, feeding a sixteen-slot matrix that reaches every parameter in the instrument. Each routing can be aimed at engine 1, engine 2, or both. The two assignable CV inputs can take any parameter over outright as a hands-on control.

Presets store the whole instrument: both engines, the filters, the envelopes, the modulation, the arpeggiator, the chords and every effect. The module keeps its state through power-off exactly as you left it, edited or not.

Specifications

• Two independent digital engines, eight voices each
• Twelve synthesis types, all resident and switchable from the panel
• Chord engine with sequencing, just-intonation and harmonic chord types
• Polyphonic arpeggiator with harmony, strum, pedal-point and generative variation
• Four mod sources, two mod envelopes, sixteen-slot modulation matrix with per-routing engine scope
• On-board stereo effects: age, bitcrusher, filter/drive, phaser, granular, delay, reverb, chorus, glitch
• Preset memory with factory and user banks
• Inputs: 1V/oct, gate, two assignable CV
• Controls: two knobs (A and B), master tune, DATA encoder, OLED display
• 44.1 kHz
• Format: Eurorack, 10 HP
• Power: +12 V @ 120 mA, −12 V @ 30 mA

Taxes and shipping

UK orders: All applicable UK taxes are included in the price shown and there are no additional UK taxes or import charges to pay on delivery.

International orders: Customers outside the UK are responsible for any import duties, VAT, sales tax, customs charges, brokerage fees or other charges imposed by their country of import.