# 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 and AUFX sound effect extension with per-head Latch/MIDI modes, LFOs, parameter automation, and preset recall — use inside any compatible DAW or host app. MIDI mode routes one channel per head (or all heads from channel 1 via the long-press MIDI toggle), with each head's pitch setting applied as an offset on the played note
- AUFX extension — use GrainHeads on an FX bus as a sound effect processor: feed any input into a buffer, use Feed/Freeze switch to lock the buffer, then play multiple heads from it with full effects and modulation
- Up to 8 independent granular playheads in standalone (up to 5 in AUv3 instrument and AUFX extension), each with its own parameters, sample slot, volume control, and dual filter system
- Dual filter per head — two independent filters with six types each (LP, BP, HP, Notch, Low Shelf, High Shelf) at 12 or 24 dB/oct, drive saturation that becomes ±12 dB shelf gain in shelf modes, parallel or serial routing, and Free/Link/Mirror cutoff relationships
- 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
- 8 LFOs with 6 waveform shapes (Sine, Triangle, Square, Sawtooth rising/falling, Sample & Hold), LFO-to-LFO modulation, and Lock LFO (sync to sequencer grid / host tempo)
- 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 modes: Single Head, Multi Heads, Multi Slots
- Sampl performance mode — a per-head play mode that turns the waveform into a multi-touch instrument: slice the sample into zones with draggable separators, each finger plays its own zone simultaneously (looping inside its bounds), and any subset of parameters can be macro-mapped to vertical finger position (A/B mix, scrub speed, pan, both filters' freq/res/drive, FX send, amp, delay send/feedback, reverb send/decay, lo-fi bits) for tactile transport-free performance
- 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
- [GrainHeads vs Quanta Comparison](https://grainheads.app/comparison.html): Buyer's guide comparing GrainHeads with Quanta Granular Synth on iOS — covers AUv3 instrument and effect support, multi-playhead motion, summing modulation matrix, parameter-lane sequencing, live audio capture, and performance controls
- [Best iPad Apps for Sound Design (2026 Guide)](https://grainheads.app/ipad-sound-design.html): Editorial guide to the best iPad apps for sound design — host apps (AUM vs Audiobus), granular synths (GrainHeads, Borderlands, Samplr), modular environments (Drambo), samplers (Koala), AUv3 plugin notes, budget setups, and a starter workflow
- [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)