Nightly Build Audio · Grainfold for iPhone and iPad

Support

Something not working, or not sure how to do something? The answers to the common questions are below. If yours isn’t, write to us at contact@nightlybuildaudio.com with your device, its iOS version and Grainfold’s version (in Settings › About), and we’ll reply as soon as we can.

Getting started

  • Bring in a sound: tap Import to choose an audio file, or the microphone to record one. Grainfold makes a region over all of it, so Play plays it straight away.
  • Regions: drag across the waveform to choose part of the sound; drag an edge to resize it, or the bar along its top to move it. Tap + to add up to four, A to D, each with its own sound.
  • LOOP and GRAIN: LOOP repeats a region; GRAIN draws many tiny grains from it. In GRAIN, drag the diamond at the foot of the dashed position line to choose where the grains come from; while SCAN moves them, the scan line takes its place.
  • PITCH and SPEED: PITCH changes pitch and keeps the timing; SPEED changes a loop’s tempo and keeps its pitch. With the tempo on, the metronome beside SPEED fits a loop to a quarter note up to 16 bars at the tempo.
  • Presets change the sound only, never your recording or your regions. Turn any knob and the waveform shows what it does; long-press it for What’s This?, its choices and MIDI Learn.

Free and full version

  • Free: Grainfold is free to download and try, with every sound control and effect, PERFORM, the keyboard, MIDI and the spectrogram, one region and ten presets.
  • Full version: a one-time in-app purchase of $19.99 (the App Store shows the matching price in your currency) adds four regions, all 40 presets and saving your own, projects, WAV export, REC and the Audio Unit plug-ins. You pay once and it’s yours for life. There is no subscription, and nothing renews.
  • Buying: open More (•••) › Unlock Grainfold, or Settings › Full Version, or tap anything locked.
  • Restore Purchase: on a new iPhone or iPad, or after reinstalling, open More › Unlock Grainfold and tap Restore Purchase. It finds a purchase made with the same Apple Account.
  • Bought Grainfold before it was free? The full version is already yours. If it doesn’t show as unlocked, tap Restore Purchase.
  • Family Sharing isn’t available for the full version.

Playing

  • PERFORM: touch the waveform to play it: across a region sets X, up sets Y. MOTION records your gestures and loops them.
  • KEYBOARD: the piano keys symbol shows a keyboard that plays the selected region, chords included. ROOT, then a key, chooses which note plays the region as it is.
  • MIDI: connect a keyboard or controller by USB or Bluetooth; notes play the selected region, with velocity, sustain and pitch bend. To control a knob from your controller, long-press it and choose MIDI Learn. MIDI Input can be switched off in Settings.

Tempo, scanning and modulation

  • Tempo: tap BPM to enter a tempo or tap it in, and to switch on the metronome, its time signature and sound. With the tempo on, a metronome symbol appears beside SPEED, LENGTH, SPAWN RATE, the scan’s SPEED, each LFO’s RATE and the delay’s TIME: tap it and that knob snaps to the nearest note value and turns in divisions of the beat; tap it again to run free. With the tempo off, everything runs free, in seconds, per second or hertz. While a sound plays with the tempo on, lines on the waveform show where each beat falls. Setting BPM does not automatically detect or align the beats in an imported recording.
  • Cloud: choose loop, ping-pong or one-shot scanning to move the grain position through a region. Add TIME SCATTER or reverse some grains. Long-press LENGTH or SPAWN RATE to link them, keeping the overlap steady as you change either; the one that follows still turns, setting the overlap, and shows the length or rate it comes to.
  • Pitch: in GRAIN, BEHAVIOR picks each new grain’s note. FIXED keeps the sound’s own pitch; RANDOM, FLOW, MELODIC and MOTIF play notes of the SCALE and ROOT you choose, within RANGE. Long-press BEHAVIOR for a new sequence of notes.
  • LFO: each region has two LFOs. Choose a destination, waveform, rate and depth; enable sync or retrigger when useful.
  • Envelopes and effects: note and filter ADSR controls shape each voice. The FX page has LAYERS (copies of the sound an octave up or down, or a fifth up, each switched, tuned, levelled and placed from centred to wide), drive, chorus with up to six voices, DIFFUSE, delay and reverb, each switched on and off independently. In GRAIN mode it also has SPREAD, how wide the region’s grains sit, from centred to wide.
  • The waveform: the original sound is always shown, fainter inside the regions, and processed regions are coloured by what each effect adds. A GRAIN region lights up where its grains are playing; at rest, the next grain is outlined at its position, as long as LENGTH and as tall as LEVEL, with JITTER as a soft wash around it. A line follows the scan, and each LFO draws its wave, labelled with what it moves. The source file remains unchanged.
  • Spectrogram: the mountains button in the waveform’s top-right corner shows a live 3D spectrogram of what’s playing: frequency across, the last two and a half seconds receding, level rising from blue to red. The waveform button in the same corner brings the waveform back. In EDIT, drag to turn it, pinch to zoom and double-tap to put it back; in PERFORM mode your fingers still play beneath it. The picture-in-picture button docks a small spectrogram on the waveform instead: drag it to any corner, tap it for full size, and its × puts it away.

GarageBand and other Audio Unit hosts

Open Grainfold once, then add it as an Audio Unit instrument in your host. Load a project or import audio in the instrument, and play it from the host’s keyboard or MIDI. Each host project keeps its instrument state; tempo sync can follow the host.

To sample another track, insert Grainfold Capture as an Audio Unit effect. Capture a free take or 1, 2 or 4 bars, then choose Save to Grainfold. The take appears in the instrument’s Captures library. Capture passes the track’s audio through unchanged.

Recording and sharing

The microphone records a new source sound. The transport’s REC button records your performance, including keys, gestures and effects, as a 32-bit float WAV. After stopping, choose Export to DAW to send it to a folder in Files or iCloud Drive. Share a complete project as a .grainfold file to include its sample and settings.

If something isn’t right

  • A knob is greyed out: it does nothing as the sound is set now, for example an effect that’s switched off, or the filter set to OFF, so it doesn’t turn. Tap it to see what turns it on.
  • No sound: check the volume and which speaker or headphones the sound goes to, and that the region isn’t muted (M) or silenced by another’s solo (S).
  • Recording doesn’t start: Grainfold needs microphone access, which you can allow in Settings › Privacy & Security › Microphone.
  • A MIDI device doesn’t play: the KEYBOARD panel shows what is connected. Check MIDI Input is on in Grainfold’s Settings, and reconnect the device.
  • Crackles on an older device: turn on Light Mode in Settings, which plays fewer grains at once at the densest settings.
  • Where are my files? Recordings and exports are in the Files app, under On My iPhone (or On My iPad) › Grainfold.

Privacy

Grainfold collects nothing, and everything you make stays on your device. See the privacy policy.