# GrainHeads

> GrainHeads is a granular synthesizer for iPhone and iPad. It takes any audio sample, splits it into tiny overlapping fragments called "grains," and plays them back in configurable streams to create evolving textures, rhythmic patterns, ambient pads, and glitchy soundscapes. Built for sound designers, musicians, and experimental producers who want deep control over their textures.

## About

GrainHeads is an iOS app available on the App Store. It requires iOS 17.0 or later. The app offers a free version with a single one-time purchase to unlock the full experience.

## Key Features

- AUv3 Audio Unit plugin with per-head Latch/MIDI modes, LFOs, parameter automation, and preset recall — use inside any compatible DAW or host app
- Up to 8 independent granular playheads, each with its own parameters, sample slot, volume control, and modulatable Moog-style ladder filter (LP/BP/HP, 12dB/24dB slope, resonance, drive)
- 4 sample slots — load different samples simultaneously, each head picks its own slot (LFO-modulatable for dynamic sample switching)
- Per-head grain controls: Position, Scatter, Grain Size (10ms–5s), Grain Rate, Grain Chance, Pitch (-24 to +24 semitones), Reverse, Envelope, Pan, Pan Spread, Amplitude, FX Send
- Bezier curve grain envelope editor — draw any custom envelope shape per head, in addition to Hann, Gaussian, and Trapezoid presets
- 8 LFOs with 6 waveform shapes (Sine, Triangle, Square, Sawtooth rising/falling, Sample & Hold) and LFO-to-LFO modulation
- Every parameter can be modulated by any LFO, including effect parameters
- 16-step sequencer with per-step pitch, size, position, chance, and lockable overrides (reverse, pan, filter freq, filter res, filter drive)
- Clock dividers from /64 to x64 per head for polyrhythmic sequences with independent per-head step lengths and start points
- Multi-touch 2D XY performance pad with 4 fingers / 8 simultaneous parameters in three modes: Single Head, Multi Heads, Multi Slots
- Re-routable effects chain: Noise (White, Vinyl, Waves), Stereo Delay (BPM-syncable), Reverb with LP/HP filtering
- Ableton Link for tempo sync across apps and devices
- Brickwall output limiter with configurable threshold, attack, and release
- Scale quantization: Free, Chromatic, Major, Minor, Harmonic Minor, Melodic Minor, Pentatonic Maj/Min, Blues, Dorian, Phrygian, Lydian, Mixolydian, Whole-Half, Whole Tone
- Undo / redo up to 3 preset changes
- Adjustable maximum grain length (2 seconds default, up to 5 seconds)
- Full UI customization — toggle background video, pick custom colors for any element
- Audio recording with save, share, and reimport
- Sample import (WAV, AIFF, M4A, MP3, CAF) and microphone recording
- Preset save/load/export/import (.ghpresets files) with full state preservation
- Dice randomizer for heads, sequences, effects, and LFOs

## Pages

- [Home](https://grainheads.app/): Main landing page with features overview and download link
- [How to Use](https://grainheads.app/how-to-use.html): Complete guide to using GrainHeads — heads, sequencer, touch pad, effects, LFOs, AUv3, Ableton Link, and presets
- [Privacy Policy](https://grainheads.app/privacy.html): Privacy policy covering data collection, Firebase Analytics, Firebase Crashlytics, and RevenueCat
- [Contact](https://grainheads.app/contact.html): Contact form to reach the GrainHeads team
- [Detailed LLM reference](https://grainheads.app/llms-full.txt): Full feature documentation for AI assistants

## Download

- [App Store](https://apps.apple.com/app/grainheads/id6760582834)