Choral Lab vs MusicBall

Choral Lab brings the art of four-part Bach chorale writing to your iPhone. Whether you're a composer, music student, or theory enthusiast, explore one of the most refined harmonic styles in Western music. Harmonize your melodies. Draw a soprano line on the interactive piano roll and watch Choral Lab instantly generate alto, tenor, and bass voices following authentic Bach voice-leading rules — avoiding parallel fifths and octaves, resolving leading tones, and building natural cadences. Browse 410 Bach chorales. Explore the complete corpus of J.S. Bach's four-part chorales with full score display, real-time chord analysis, and playback with rich choir sounds. Two ways to read the music. Switch between a traditional four-part score view with proper notation and clefs, or a piano roll view to see the voice leading clearly laid out across time. Mute individual voices to focus on any single part or study how voices interact. Generate original chorales. Let the app create complete chorales from scratch in any key — major or minor — with realistic harmonic progressions, passing tones, and Picardy thirds. Study chord analysis. Follow along with real-time Roman numeral chord labels as the music plays. Features: • Interactive soprano piano roll with tie support • Automatic SATB harmonization in Bach style • Library of 410 J.S. Bach chorales • Score view with Bravura music engraving font • Piano roll view with per-voice muting • Real-time chord analysis • Choir, piano, and organ sounds • MIDI export • AUv3 plugin — works in GarageBand, AUM and other hosts • One-tap host tempo sync in plugin mode • MIDI output per voice (soprano, alto, tenor, bass on channels 1–4)

Drop in a song. Watch a machine get built to play it. MusicBall takes a piece of music and constructs a whole contraption around it — plates, curving rails, spiralling drops. Then a ball falls through the lot, and every note you hear is the ball hitting something. It's oddly hard to stop watching. EVERY SONG GETS ITS OWN MACHINE Change the song and everything changes. A gentle piece grows tall spirals the ball winds slowly down through. A fast one packs tight columns it ping-pongs between. Switch back and forth and you'll never see the same machine twice. YOU'LL START TO SEE THE MUSIC Every note has its own colour, and it keeps that colour wherever it turns up. A few minutes in and you're spotting a melody's repeats on the wall before you hear them come round again. PICK WHO PLAYS THE MELODY Hand the tune to a different part and the whole machine rebuilds around it. Or let the spotlight travel between parts as the piece goes on — the ball slides across to a new rig each time the lead changes. Or run two balls at once, side by side. EVERY HIT LANDS ON THE BEAT The ball never fakes it. It arrives exactly when the note does, every single time — so what you're watching and what you're hearing are the same thing happening. BRING YOUR OWN FAVOURITE Seven classics are built in to get you started: Canon in D, The Entertainer, Turkish March, In the Hall of the Mountain King, Für Elise, Prelude in C and Gymnopédie No. 1. After that, bring in anything you like — your file stays on your phone. FLY THE CAMERA Ride along with the ball, or take over: spin around it, pan across the machine, pinch to take in the whole thing at once. NOTHING TO SIGN UP FOR No account. No ads. No tracking, nothing collected. It works exactly the same in Airplane Mode.