Strange Loops Audio's FREE gRainbow Synth.
- Vasanth David

- Jul 16, 2024
- 2 min read

Price : FREE
grainbow is an open-source, cross platform synthesizer that uses pitch detection to choose candidates for granular synthesis or sampling.
gRainbow was created to overcome a few shortcomings of traditional granular synths.
Pitch variations in the input clip can produce inharmonic tones, which isn't always wanted. This leads users to often use short single-pitch clips, restricting the synth to a single timbre.
Manual pitch matching to the input clip is often required to produce the correct notes with MIDI input, which can be difficult and repetitive.
Pitch shifting is commonly done with timestretching, which can create unwanted artifacts when shifting multiple octaves in either direction.
Instead, gRainbow prefers longer, pitch-diverse audio clips (1), automatically produces harmonics matched for MIDI input (2) and avoids too much timestretching by generating harmonics that are already near their target pitch (3). Voila!
Features
Full MIDI range, polyphonic voicing
Quick and reliable pitch detection using Spotify's BasicPitch machine learning model
Up to 150 grains playing at once
Ultra-customizable parameters that can be overriden at the per-note and per-generator level
Grain envelope shape, tilt, rate and duration parameters
Pitch, pan and grain position spray and adjustment parameters
Play grains in forward or reverse
Option to sync rate parameters to the host BPM
Option to play a reference tone for each note to help dial in pitches
and more!
Full internal modulation and mapping system
Amplitude envelope and 2 additional envelope modulators
3 LFO modulators
4 macros
Preset loading and saving system that bundles the audio sample into the preset for you - Cute clouds that sing!
System Support
▷ Mac,Windows and Linux
▷ VST | AU | LV2
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gRainbow's approach to granular synthesis, especially its AI-driven harmonic matching, is genuinely groundbreaking. This free synth looks like a powerful solution for creative sound design. Find more tools at Tunerninja.