Sound basics

Tono turns instructions into sound. Choose notes, decide when they play, and give them an instrument. Start by listening to this phrase, then follow the Rust and Python lessons below.

Hear what changes

One phrase. Four things to change.Change a setting, then press play.

Pitch C3 · lowC4 · middleC5 · highFirst note: 261.6 HzInstrument PianoPluckSine toneThe character of each noteTempo

120 BPM

One beat: 0.50sNote length Half a beatOne beatHow long each note lasts

1. Beat 1C4
2. Beat 2E4
3. Beat 3G4
4. Beat 4C5

One bar = 4 beats = 2.00 seconds. Shorter notes leave space before the next beat.

Plays one bar.

Try one change at a time: raise Pitch to hear the whole phrase higher, increase Tempo to hear it faster, then switch Instrument to change its character. Shorter Note length ends each note earlier, leaving a rest before the next note. Note starts stay on the same beats.

The building blocks

Concept	What you create in tono	What it changes
Pitch	A note such as C4 in a song, or 440 Hz on a raw oscillator	How high or low a tone sounds
Tempo	A song’s BPM, such as 120	How quickly beats pass; 120 BPM means two beats per second
Instrument	A piano, bass, drum kit, or synthesized voice	The character of the sound, called its timbre
Note	A pitch, start time, and duration	One event: what plays and when
Pattern / sequence	A group of timed notes	A reusable melody, rhythm, or chord progression
Track	An instrument and the patterns assigned to it	One part of a song, with its own mix settings
Arrangement	Patterns placed at particular bars	When each part enters, repeats, or stops
Envelope / effects	Volume shape, filtering, delay, and other processing	How a note starts, fades, and sounds

A beat is a regular pulse. A bar groups beats; the examples use four beats per bar, called 4/4 time. At 120 BPM, one beat lasts 0.5 seconds and one four-beat bar lasts 2 seconds.

How a song becomes audio

Timed notes → Pattern
Instrument → Track
Pattern placements on tracks → Song

Song → compile → Program → render → Audio samples → WAV

Create a Song with a tempo, give a track an instrument, make a Pattern of notes, and arrange that pattern on the track. Compiling checks the score and produces a Program, a reusable bundle containing the resolved sound graph. Rendering produces numbers representing the audio waveform.

You can also create a sound effect directly as a SoundDoc: a JSON graph of sound sources and processing nodes. A seq node is the lower-level sequencer used for timed notes; the Song and Pattern APIs handle this graph for you. A one-shot laser or impact can use oscillators, noise, and envelopes without needing a song.

Learn in order

1. Install tono and render your first sound.
2. Pitch and notes: name a note, move it up an octave, and create a phrase.
3. Tempo and patterns: place notes on beats, create rests, and repeat a pattern.
4. Instruments and tone: play the same phrase with different voices and shape its sound.

Then use the task guides to compose songs, design effects, or run scheduled audio.

Samples, seconds, and sound files

An audio sample is one amplitude value. A frame contains one sample per channel. Sample rate tells you how many frames are produced per second. At 48 kHz, a one-second mono render has 48,000 samples. Stereo has a left and right sample for every frame. Sample rate controls how densely audio is sampled; tempo controls musical timing.

For a mono SoundDoc, Rust’s renderer returns Vec<f32> and Python’s returns a NumPy float32 array. For a song, Rust’s render_stereo() returns separate left and right vectors; Python’s Program.render() returns an array shaped (frames, 2). A WAV stores those samples with metadata such as sample rate and channel count. Rendering creates audio; opening a WAV in a player or starting a playback runtime lets you hear it.

Keep the editable Song or SoundDoc recipe with the WAV so you can change it and render again. A saved Program can be reloaded for playback or rendering without compiling the score again.