vxn-2b (“vixen 2b”) is a six-operator FM synthesizer and the successor to VXN2. Six sine oscillators, thirty-two ways of wiring them to each other, and a stacking engine that turns one note into eight — now on a new faceplate of rubber knobs and green LCD panels, with cleaner FM at every setting. It is coming as a CLAP plugin for macOS and Windows, with VST3 to follow, and you can play it now in your browser: the web build is the same engine and the same faceplate, compiled to WebAssembly.
FM is where the bells, electric pianos, glassy basses and metallic stabs come from — sounds that no amount of filtering will get you out of a sawtooth.
The voice
Six operators. Which ones you hear, and which ones bend the others, is set by the algorithm: thirty-two arrangements, drawn on their own LCD and changed with a single control, and changing it never disturbs the values you have dialled into the operators themselves. One operator in each arrangement feeds back into itself, running from a pure tone at zero to chaos at full.
The operators are pure sines, and modulation wraps rather than clips, so a modulator at full level bites at its full depth. QUALITY sets how far the voices are oversampled: Standard runs them at the host’s rate, or twice it while the filter is on, and High at four times, for high notes, deep modulation and heavy feedback without folded-back aliasing.
Voice stacking
Play one note and hear up to eight.
Detune fans the lanes out in pitch, up to fifty cents, while the centre lane stays put, so a patch thickens without the pitch wandering off. Space the lanes evenly for a smooth chorus, cluster them to keep most of the stack close to the centre, or scatter them so no two notes come out quite alike.
Phase spread sets how the stack starts. Line the lanes up and the attack is hard and immediate. Push them apart and the note softens and shimmers into being.
Spread is a modulation source in its own right, so what varies across the stack is yours to choose. Route it to pan and one note fills the stereo field. Route it to a modulator’s level and the stack grades from clean at its centre to biting at its edges — several timbres inside a single note.
Per-operator control
Every operator has its own four-stage envelope and key scaling, drawn on the operator’s LCD and edited by dragging their points. Tuning is by ratio, with just intervals and a continuous fine offset, or fixed frequencies for bells, mallets and struck metal. All six operators’ levels, pans and phases sit on one plate, so a patch’s balance is visible at a glance.
Modulation
Two LFOs — one shared across the patch and tempo-syncable, one per voice with delay and fade-in. A pitch envelope that can swing up or down into a note. A spare delay-attack-hold-decay-sustain-release envelope with no fixed job. All of it lands in a sixteen-slot matrix that reaches per-operator pitch, level and pan, the filter, the stack and the effects, through linear, exponential, logarithmic or bipolar curves. A route that can’t work as set is flagged in red.
Filter and effects
A ladder filter sits after the stack, off by default and out of the signal path when it is: low-pass, high-pass, band-pass or notch, 12 or 24 dB/octave, with drive for colour and self-oscillation at full resonance. Turned on at its defaults it is open, so it changes nothing but cleans up. A high-pass on the sum sets the low-end weight. Then dynamics, phaser, delay and reverb, and a limiter.
Voicing and presets
Up to sixteen voices, or Solo with legato and portamento. The factory bank is VXN2’s fifty-one presets, carried over and re-voiced for the new engine, plus new ones. The manual describes every control, with graphs measured from the synth’s own code.