If you like granular effects that are easy to use and easy on the wallet, check out FRCTL’s GRN. With just a handful of knobs, it’s simpler than some deeper granular plug‑ins (eg. Output Portal, Arturia Efx Fragments and Brainworx Silo), but can conjure up a surprisingly wide and very useful range of effects, from smooth washes and pulsing octaves to glitchy delays. Even if you already have a granular delay plug‑in or two, you may well find that GRN can deliver sounds they can’t. It comes with a range of presets, as well as a random dice button that can sometimes create something interesting.
Supporting AU, VST3 and CLAP formats and Windows, Linux and macOS, GRN extracts grains from a 2.7‑second audio buffer and processes them with up to ±2 octave pitch‑shifting and Jitter, which adds random pitch modulation. There’s also the option to have a percentage of grains reversed randomly.
The Size control sets the grain lengths, while Density sets how many grains are generated per second — a nice touch is that Density can be tempo‑sync’ed to a choice of note divisions. Spread sets the stereo width, while Scatter progressively randomises the grain generation timing by reaching back to earlier parts of the buffer. Pitch is freely variable over its range, and there’s the usual wet/dry Mix control below. There’s also a control section for feedback around the delay buffer, to add further repeats and coloration, and a Freeze function. Jitter’s Q button quantises the pitch variations according to a Scale Quantise setting, while Output adjusts the overall output level and offers automatic level compensation. Clicking Feedback opens a panel where the feedback (up to 95 percent), HF damping and drive can be adjusted.
The ability to force pitch‑shifted grains into a musical key opens up the possibility of more musical‑sounding granular effects.
So far that might not sound radical, but the ability to force pitch‑shifted grains into a musical key (Scale Quantise can be set to any major or minor key, normal or pentatonic) opens up the possibility of very musical‑sounding effects. And if the Q button is active in the Jitter section, its random pitch variations are also forced into the scale key. (The other settings are Free or Chromatic.) Variable high‑ and low‑pass filters can be used to shape the affected sound, and a Harmony menu lets you to add octave up, octave down, fifths or random octave shifts. Dynamic displays show the effect waveform, the frequency spectrum and the creation of grains. With the feedback turned up, the delays can hang around for a long time and there’s provision to EQ the feedback path.
If you push the grains up by an octave, add some Jitter and set both the Size and Density controls to around half way, the effect is not unlike hearing a tape played at high speed, with music in the same key as your Scale setting. Shorten the grain size and the result suggests musical water drips. Use it on piano and you can get some beautifully fluttery delays, with or without scale quantise, and if you don’t want to take risks, you can always stick to octaves or fifths. The octave‑up settings produce a fluttery shimmer at larger grain sizes.
Considering the modest cost and the range of genuinely useful effects it can produce, GRN should appeal to any user of granular delays. The review started with v1.9.1, but by the time I’d finished the developer had updated GRN to 2.1.2, adding two LFOs that can be dragged onto any knob for control, and a comprehensive effects section, in which any effect parameter can also be brought under LFO control. A free but vastly simplified Lite version is available too... but this full version offers so much more!