Instruments

Instruments turn patterns into sound.

Synthesizers

Built-in waveform synthesizers:

[C4 E4 G4] |> saw        // Sawtooth wave
[C4 E4 G4] |> sine       // Sine wave
[C4 E4 G4] |> square     // Square wave
[C4 E4 G4] |> triangle   // Triangle wave
[C4 E4 G4] |> noise      // White noise
[C4 E4 G4] |> supersaw   // Detuned saw stack

FM Synthesis

FM (Frequency Modulation) synthesis creates complex timbres by having one oscillator modulate another's frequency. Great for bells, electric pianos, and metallic sounds.

[C4 E4 G4] |> fm                              // Default FM sound
[C4 E4 G4] |> fm(ratio: 2.0, index: 5.0)      // Custom ratio and depth
[C4 E4 G4] |> fm(ratio: 1.0, index: 3.0, feedback: 0.2)  // With feedback

Parameters:

Parameter	Description	Default
`ratio`	Modulator/carrier frequency ratio. Integer ratios (1, 2, 3) sound harmonic; non-integer ratios sound metallic/bell-like	2.0
`index`	Modulation depth. Higher = more harmonics/brightness. 0 = pure sine	5.0
`feedback`	Self-modulation amount (0.0-1.0). Adds grit and complexity	0.0

Classic FM sounds:

// Electric piano (Rhodes-like)
play [C4 E4 G4] |> fm(ratio: 1.0, index: 3.0) |> adsr(0.01, 0.3, 0.4, 0.5)

// Bell/chime
play [C5 E5 G5] |> fm(ratio: 3.5, index: 6.0) |> adsr(0.01, 0.5, 0.2, 1.0)

// Aggressive bass
play [C2 _ C2 _] |> fm(ratio: 0.5, index: 8.0, feedback: 0.3)

Samples

Load and play audio samples. Supported formats: WAV, FLAC, and MP3.

// Basic sample playback
let kick = sample("lib:drums/kick.wav")

// Melodic samples with root note
let glass = sample("lib:wine-glasses/glass1", root: C4)

// Use melodic sample with pattern — pitch-shifted from root
[C4 E4 G4] |> glass

The root: parameter tells Sanic Boom which note the original sample was recorded at. When you play different notes, the sample is pitch-shifted to match. This turns any single sample into a playable instrument.

Sample Libraries

Import sample packs from the sample library catalog:

import "github:SanicBoom/wine-glasses"

// Reference samples as lib:library-name/sample-name
let glass = sample("lib:wine-glasses/glass1", root: Eb4)
[Eb4 G4 Bb4] |> glass |> reverb(0.7)

Browse all 150+ available libraries in the Sample Libraries page.

Reverse Playback

sample("lib:drums/snare.wav") |> reverse

Start/End Positions

Play a portion of a sample using begin and end (0–1 normalized range):

// Play the second quarter of a break
sample("break.wav", begin: 0.25, end: 0.5)

// Pipe syntax
sample("break.wav") |> begin(0.25) |> end(0.5)

// Combine with other effects
sample("break.wav") |> begin(0.5) |> end(0.75) |> reverb(0.6)

begin — Start position (0–1, default 0)
end — End position (0–1, default 1)

Sample Slicing

Slice samples for breakbeat-style manipulation:

let break = sample("break.wav") |> slice(8)

// Access individual slices
[break[0] break[2] break[1] break[3]]

Per-Note Instruments

Place instrument values directly inside patterns to trigger different samples per step — no need for separate lanes:

import "github:SanicBoom/808"
from "github:SanicBoom/808" import { kick, snare, hat }

play [kick _ snare hat]

Each name resolves to a sample instrument, so the pattern plays kick on beat 1, snare on beat 3, and hat on beat 4. You can mix instruments freely:

from "github:SanicBoom/808" import { kick, snare, hat, clap }

play [kick hat snare hat | kick hat clap hat]

Per-note instruments work with all note modifiers — probability, velocity, and duration weights:

play [kick snare?0.5 hat@0.6 hat:2]

This is equivalent to writing separate stack()ed lanes but much more concise for drum patterns.

Pitch Modulation

Glide (Portamento)

Smooth pitch sliding between consecutive notes:

|> glide(0.1)          // 100ms glide time
|> glide(50ms)         // Using milliseconds
|> glide(time: 100ms)  // Named parameter

Essential for 303-style acid basslines:

let acid = [C2 C2 Eb2 C3]
    |> saw
    |> glide(80ms)
    |> lowpass(800)

Pitch Envelope

Modulate pitch over the note's duration:

|> pitchEnv(start: 2, end: 1, time: 0.05)   // Kick drop
|> pitchEnv(start: 0.5, end: 4, time: 0.2)  // Laser rise
|> pitchEnv(start: 1, end: 1.05, time: 0.1) // Subtle rise

Parameters:

Parameter	Description
`start`	Starting pitch multiplier (2 = octave up)
`end`	Ending pitch multiplier (1 = normal)
`time`	Time to reach end pitch in seconds

Classic psytrance kick with pitch drop:

let kick = [C1]
    |> sine
    |> pitchEnv(start: 3, end: 1, time: 0.03)
    |> adsr(0.001, 0.1, 0, 0.1)

Combining with Effects

Chain instruments with effects:

[C4 E4 G4]
    |> supersaw
    |> lowpass(2000)
    |> reverb(0.6)
    |> delay(0.25)

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