SlicBeat Documentation

Getting Started

SlicBeat is a tracker-style music production app for iOS. If you've used trackers like LSDJ, Renoise, M8, or the Polyend Tracker, you'll feel right at home. If you're new to trackers, here's the key concept: music is composed on a vertical grid where notes scroll downward, step by step.

Creating Your First Project

When you launch SlicBeat, it automatically loads your last project. To create a new one, tap the folder icon in the transport bar to open the Project browser, then tap + to create a new project.

Adding an Instrument

Tap the waveform icon in the transport bar to open the Instruments panel. Tap + to add an instrument. You can choose from:

• Default Samples — Browse the bundled sample library
• Browse Files — Import your own audio files (WAV, AIF, MP3, M4A, CAF)
• Synth Instrument — Create a synthesizer using one of 24 Plaits engines
• MIDI Instrument — Route to an external MIDI device
• Load Preset — Load a previously saved instrument preset

Writing Your First Pattern

The main tracker grid shows one phrase at a time. Each phrase has 16 steps. Tap a cell to open the step editor, where you can set the note, instrument, volume, and up to 3 effect commands. Place notes on different steps to create a rhythmic pattern, then press play to hear it loop.

Interface Overview

Transport Bar

The transport bar sits at the top of the screen and contains:

• Play/Pause — Start or pause playback. Double-tap to restart the song from the beginning.
• Stop — Stop playback and reset the playhead.
• BPM — Shows the current tempo. Tap +/- to adjust by 1 BPM, or drag vertically on the number to scrub the tempo smoothly.
• Waveform icon — Open the Instruments panel.
• Slider icon — Open the Mixer.
• Folder icon — Open the Project browser.

Breadcrumb Navigation

Below the transport controls, breadcrumbs show your current location in the song hierarchy: Song → Chain → Phrase. Tap any breadcrumb to navigate back to that level.

Tracker Grid

The main grid displays the current phrase for each track. Each column represents a track, and each row is a step. The columns within each track show:

• Note — The musical note (e.g., C-4, F#5) or OFF for note-off
• Instrument — Which instrument to trigger (hex value: 00-7F)
• Volume — Step volume (hex value: 00-FF)
• FX — Up to 3 effect commands per step

Tap a cell to edit it. Long-press for copy/paste/clear options.

Phrases & Steps

Phrases are the building blocks of your music. Each phrase contains 16 steps, and the sequencer plays them from top to bottom. There are 256 phrases available (indexed 00 to FF in hexadecimal), shared across all tracks.

Step Editor

Tapping a cell in the tracker grid opens the step editor. Here you can set:

• Note — Choose from a full 10-octave range (C0 to C9, 120 MIDI notes). Select OFF to send a note-off command that releases the current note.
• Instrument — Select which instrument this step triggers. If left empty, the step uses the track's last-set instrument.
• Volume — Override the note velocity for this step (00 = silent, FF = maximum).
• Effects 1-3 — Up to three effect commands. Each has a type letter and a hex value. See the Step Effects Reference for details.

Copy, Paste, and Clear

Long-press on any step to bring up the context menu. You can copy a step's contents, paste from the clipboard, or clear the step entirely.

Chains

Chains link multiple phrases together into a longer sequence. Each chain can hold up to 16 entries, where each entry references a phrase and optionally applies a transpose value (in semitones). This lets you reuse the same phrase at different pitches.

Navigate to the Chain view by tapping the chain breadcrumb in the transport bar. Select which phrase plays at each position, and set transpose values to create melodic variations without duplicating phrases.

Song Mode

The Song view is the top-level arrangement. It's a grid of up to 256 rows × 8 tracks. Each cell references a chain. The sequencer plays each row from left to right (all 8 tracks simultaneously), then moves to the next row.

Navigate to Song mode by tapping the "Song" breadcrumb. Assign chains to each track at each row to build your full song structure. Empty cells are silent for that track.

During playback, the song progresses row by row. When it reaches the end of the populated rows, it loops back to the beginning.

Instruments

SlicBeat supports three instrument types, all accessible from the Instruments panel.

Sample Instruments

Load audio samples and play them back at different pitches. Supported formats: WAV, AIF, AIFF, MP3, M4A, CAF.

Sample instrument parameters:

• Volume — Base playback volume
• Panning — Stereo position (left to right)
• Pitch / Base Note — The note at which the sample plays at its original pitch. Notes above or below are resampled.
• Loop Start / End — Define a loop region within the sample for sustained playback.

Every new sample instrument comes with a default AHD envelope on volume (Modulation Slot 1), so notes naturally decay rather than playing the full sample.

Synth Instruments

Create a synthesizer powered by the Mutable Instruments Plaits engine. Choose from 24 synthesis algorithms across four categories:

Classic Synthesis: Virtual Analog + VCF, Phase Distortion, 6-Op FM (3 patch structures), Waveshaping

Digital Synthesis: Granular, Additive, Wavetable, Wave Terrain, Harmonic Chord, Speech Synthesis, Chiptune, String Machine

Physical Modeling: Physical String, Modal Resonance, Particle Swarm, Noise Generator, Particle Synthesis

Drum Synthesis: Bass Drum, Snare Drum, Hi-Hat

Each synth engine exposes five core parameters:

• Harmonics — Controls harmonic content and overtone structure
• Timbre — Shapes the tonal character of the sound
• Morph — Smoothly morphs between synthesis modes within the engine
• Decay — Controls the amplitude decay envelope
• LPG Colour — Blends between VCA (clean) and VCF (filtered) behavior, emulating a low-pass gate

MIDI Instruments

Route note data to external MIDI hardware or virtual MIDI apps. Configure the MIDI channel (1-16) and select the destination from available MIDI outputs. MIDI instruments send note-on, note-off, and velocity information in real-time.

Modulation System

Each instrument has 4 modulation slots. Every slot connects a source to a destination with an adjustable amount (-100% to +100%).

Modulation Sources

AHD Envelope (Attack-Hold-Decay)
A three-stage envelope that rises, holds, then falls. Parameters: attack time, hold duration, decay time. When all volume-targeting AHD envelopes finish, the voice automatically stops.

ADSR Envelope (Attack-Decay-Sustain-Release)
A classic four-stage envelope. Parameters: attack time, decay time, sustain level, release time. The sustain stage holds as long as the note is on; release triggers on note-off.

LFO (Low-Frequency Oscillator)
A cyclical modulator with six waveform shapes: Triangle, Sine, Ramp Down, Ramp Up, Square, Random. Control the rate, or set a tempo-synced period in 16th-note steps. Three trigger modes:

• Free — Runs continuously regardless of note events
• Retrig — Resets phase on each new note
• Once — Plays one cycle then stops

Tracking
Maps an input value (note pitch or velocity) to the modulation output with configurable input and output ranges. Useful for velocity-sensitive volume or pitch-dependent filter sweeps.

Modulation Destinations

• Volume — Multiplies the instrument volume (available for all types)
• Pitch — Offsets the pitch in semitones (available for all types)
• Filter Cutoff — Modulates the filter cutoff frequency (sample & synth)
• Filter Resonance — Modulates filter resonance (sample & synth)
• Harmonics — Modulates the synth harmonics parameter (synth only)
• Timbre — Modulates the synth timbre parameter (synth only)
• Morph — Modulates the synth morph parameter (synth only)
• Decay — Modulates the synth decay parameter (synth only)
• LPG Colour — Modulates the synth LPG colour parameter (synth only)

Filters

Each sample and synth instrument has an optional filter section with 7 filter types:

Standard Filters

• Low Pass — Removes frequencies above the cutoff, creating darker tones
• High Pass — Removes frequencies below the cutoff, thinning out the low end
• Band Pass — Passes only a narrow band around the cutoff frequency
• Notch — Removes a narrow band around the cutoff, passing everything else

Vintage Emulations

• MS-20 Low Pass — Inspired by the Korg MS-20. A 12dB/octave filter with aggressive resonance and tanh saturation in the feedback path, creating the characteristic screaming self-oscillation.
• Oberheim SEM — Inspired by the Oberheim SEM. A 12dB/octave state-variable filter with gentle, musical resonance. Known for its smooth, warm character.
• Moog Ladder — Inspired by the Moog transistor ladder. A 24dB/octave (4-pole) cascade filter with rich, creamy resonance. The classic subtractive synthesis filter.

Each filter has two main controls:

• Cutoff — The filter frequency (0-100%)
• Resonance — How much the filter emphasizes frequencies near the cutoff (0-100%)

Filters also have a dedicated filter envelope (ADSR) that modulates the cutoff over time. This is separate from the 4 modulation slots and provides independent envelope control for the filter.

Step Effects Reference

Each step can have up to 3 effect commands. Each command consists of a type letter and a hexadecimal value (00-FF).

Global Effects

SlicBeat has three global send effects. Each track has independent send levels, so you can blend the effect amount per track.

Delay

A tempo-synced delay with filtered feedback. Available delay times:

• 1/32, 1/16, 1/8, 1/4, 1/2, 1/1 (whole note)
• Dotted variants: 1/16d, 1/8d, 1/4d, 1/2d

Parameters:

• Time — Delay length, synced to the project BPM
• Feedback — How much of the delayed signal feeds back into the input (0-100%)
• HP Filter — High-pass filter on the feedback path to thin out repeats
• LP Filter — Low-pass filter on the feedback path to darken repeats
• Volume — Wet signal level

Reverb

A Freeverb-style algorithmic reverb with 8 parallel comb filters and 4 series allpass filters.

• Room Size — Controls the size of the virtual space (0-100%)
• Damping — High-frequency absorption (0-100%, higher = darker reverb)
• Mod Depth — Subtle pitch modulation for richer reverb tails
• Mod Freq — Speed of the modulation
• Volume — Wet signal level

Mod FX

Three modulation effect algorithms, selectable per project:

• Chorus — Thick, lush doubling effect using modulated delays (5-25ms range)
• Phaser — 6-stage allpass chain sweeping from 200-4000 Hz for classic phase shifting
• Flanger — Comb-filter effect with short modulated delay (0.5-5ms) and feedback

Parameters (shared across all three):

• Rate — LFO speed of the modulation
• Depth — Intensity of the modulation
• Mix — Wet/dry blend

Mixer

The Mixer gives you per-track control over the final mix. Open it by tapping the slider icon in the transport bar.

Per-Track Controls

• Volume — Track output level (0-100%)
• Pan — Stereo position (full left to full right)
• Mute — Silence the track without removing it from the arrangement
• Solo — Listen to only this track (mutes all others). Multiple tracks can be soloed simultaneously.

Send Levels

Each track has independent send amounts for the three global effects:

• Delay Send — How much of the track goes to the delay effect
• Reverb Send — How much of the track goes to the reverb
• Mod FX Send — How much of the track goes to the modulation effect

Instrument Presets

Instrument presets let you save and reuse instrument configurations across different projects.

Saving a Preset

Open any instrument in the Instrument Editor, scroll down to the Presets section, and tap Save as Preset. Give it a name, and the complete instrument configuration (type, parameters, modulation slots, filter settings) is saved.

Loading a Preset

There are two ways to load a preset:

• From the + menu — Tap + in the Instruments panel and choose "Load Preset" to create a new instrument from a saved preset.
• From the Instrument Editor — Open an existing instrument, scroll to the Presets section, and tap "Load Preset" to replace the current instrument's settings with a saved preset.

Presets include all instrument settings: synth engine and parameters, sample filename, filter configuration, and all four modulation slots. Sample files must still be available in the project for sample-based presets to load correctly.

Project Management

Creating a Project

Tap the folder icon in the transport bar to open the Project browser. Tap + to create a new project. Each project gets its own directory for samples and settings.

Saving

Projects save automatically when you make changes. The project file is stored as JSON alongside any imported samples.

Auto-Load

SlicBeat remembers your last project and automatically loads it on launch. Sample buffers load asynchronously in the background for faster startup times.

Managing Projects

The Project browser shows all saved projects sorted by modification date. Swipe to delete projects you no longer need.