Granular synthesis and expressive per-note control have always seemed like a natural pairing — few synthesis methods reward continuous, gestural modulation as directly as granular does — yet dedicated MPE-ready granular instruments remain rare. FRCTL Audio is looking to close that gap with GRNi, a new sample-based synthesizer plugin built around the same GRN granular engine the developer previously shipped as an effects processor.
From Processor to Playable Instrument
Where FRCTL Audio's original GRN treated granular synthesis as something you applied to a signal passing through, GRNi turns it into something you play. The plugin accepts two independent sample layers, A and B, each holding up to 60 seconds of audio at 48kHz, and makes them playable as a MIDI instrument across monophonic, legato, or fully polyphonic modes supporting up to 16 voices. Any sample — a field recording, a vocal take, a synth patch bounced to audio — becomes raw material for a granular instrument rather than a one-shot sample player.
The granular controls sit front and center: grain size, tempo-syncable density, drift, stereo width, and grain shaping give hands-on access to the texture of the sound, while per-grain filtering (cutoff, resonance, and drive) shapes tone at the most granular level possible, in the literal sense. Pitch handling goes beyond simple chromatic playback, too, with a harmony function offering scatter and direction controls for building evolving, semi-randomized pitch clusters from a single held note.
Full MPE Compatibility
The feature that separates GRNi from most granular plugins on the market is straightforward: it is fully MPE compatible. Played from an Osmose, a LinnStrument, a Haken Continuum, or any other MPE controller, per-note pitch bend, pressure, and slide map directly onto the granular engine's parameters — grain density swelling under finger pressure, pitch drifting under a slide, texture shifting independently on every note of a chord. For an engine already built around continuous modulation, MPE input is less a bolted-on feature than the interface the instrument seems designed for.
Underneath the granular layer, GRNi carries a conventional but well-specified modulation section: three multi-wave LFOs, three ADSR envelopes, and four macro controls that can be assigned across most parameters in the signal path. Each voice runs through its own resonant low-pass/high-pass filter with selectable feedback types and velocity-responsive envelopes, and the signal chain ends in a ten-slot effects section — bit-crusher, chorus, delay, phaser, reverb, flanger, distortion, tremolo, widener, and a further filter stage — positioned after the grain engine itself.
Pricing and Availability
GRNi is available now for macOS (Apple Silicon and Intel), Windows, and Linux, in VST3, AU, and CLAP formats. FRCTL Audio has set an introductory price of $34.99, rising to a regular price of $44.99 once the launch window closes. At that price point, GRNi undercuts most granular-specific instruments on the market by a wide margin, while still offering a genuinely MPE-native playing experience rather than the retrofitted expression support that's common in older granular tools.
Why It's Worth Watching
The MPE plugin landscape has, for the most part, been built around subtractive and FM synthesis, with granular treated as a specialty niche served by a handful of expensive tools. GRNi's combination of a low entry price, native Linux support (still uncommon among commercial instruments), and ground-up MPE compatibility makes it an easy recommendation for MPE controller owners looking to explore granular textures without committing to a four-figure instrument. Whether it holds up against established granular tools on sound quality alone remains to be seen, but on feature set and accessibility, it's one of the more interesting small plugin releases of the month.
More information and purchase options are available at FRCTL Audio's product page.