Sonata

Sonata is a desktop piano-practice app that turns MIDI files into an interactive falling-notes experience. Listen to a piece, isolate either hand, slow difficult passages down, loop a section, or connect a MIDI keyboard and practice until every note is right.

Features

• Load standard .mid and .midi files.
• Visualize each track as falling notes over an 88-key piano.
• Assign tracks to the left hand, right hand, or hide them entirely.
• Set each hand to Listen, Practice, or Off.
• Pause playback until the correct practice notes are played.
• Connect a hardware piano through Web MIDI with live sound and key highlighting.
• Adjust playback speed, note lookahead, lead-in time, volume, and audio output.
• Create A/B loops for focused repetition.
• Choose instruments per track and a separate instrument for live MIDI input.
• Run as an Electron desktop app or in a supported browser.

Screenshots

Load a song	Configure your practice session

Follow the falling notes	Practice one hand at a time

Getting started

Requirements

• Node.js and npm
• An internet connection the first time an instrument is loaded; audio samples are downloaded from hosted soundfont libraries
• Optional: a USB or Bluetooth MIDI keyboard

Run in development

npm install
npm run dev

This starts Vite and opens the app in Electron. To run only the browser version at http://127.0.0.1:5173:

npm run dev:web

Build the desktop app

npm run build

Installers are written to release/. For a faster unpacked development build, run:

npm run build:dir

How to use

1. Load a MIDI file.
2. Review the detected tracks and assign each one to the left hand, right hand, or Off.
3. Choose how each hand behaves:
   • Listen plays and displays the part.
   • Practice displays the part without playing it for you.
   • Off hides and mutes the part.
4. Select a MIDI input if you are using a digital piano.
5. Continue to the play screen and start practicing.

Enable Wait for correct note to make Sonata pause at each practice note until you play the matching key. Use Set A and Set B to repeat a difficult section.

Available scripts

Command	Description
npm run dev	Start Vite and Electron together
npm run dev:web	Start the browser version
npm run build:vite	Type-check and build the renderer
npm run build	Build platform installers with electron-builder
npm run build:dir	Build an unpacked desktop application
npm run start	Open Electron using the latest production build
npm run preview	Preview the Vite production build

Built with

• Electron
• React and TypeScript
• Vite
• Tone.js and soundfont-player
• @tonejs/midi
• HTML Canvas and the Web MIDI API

Audio notes

The acoustic grand uses the Salamander Grand sample set. Other instruments load from the MusyngKite General MIDI soundfont. Samples are cached by the browser after loading, but a newly selected instrument may require a short download before it can play.

For the lowest live-input latency, use the Electron app with a wired audio output. Bluetooth audio can add noticeable delay.