Piano Roll

The Piano Roll tool is a sketchpad for your playing. Hit record, play, and watch your notes appear on a scrolling piano roll — then play them back, view them as staff notation, loop them, slow them down, or export them as a MIDI file.

You can record with the mouse, your computer keyboard, or a MIDI keyboard — see Playing the keyboard and Playing with a MIDI keyboard.

Recording a take

1. Set your tempo, key, and time signature in the transport bar, and switch the metronome on if you want a click (its volume is adjustable, even mid-recording).
2. Click Record and play. The roll scrolls with you as you go.
3. Click Stop. Give your take a name and save it — it appears in your library, ready to reload any time.

Takes are stored in your browser on the device you recorded them on. To keep one permanently or move it elsewhere, use Export to download it as a standard .mid file.

Playing back

• Play / Pause / Stop control playback; drag the seek bar to jump around.
• Loop repeats the take.
• The tempo box scales playback speed — slow a passage down to study it.
• Play mode switches between Raw (exactly as you played it) and Quantized (notes snapped to the grid you choose with Grid resolution).
• The view toggle flips between the piano roll and Score view — your take as staff notation, barred by the key and time signature you've set. The score is a best-effort interpretation of your timing; see From MIDI to score for what to expect.

Playing along with a MIDI guide

Load any MIDI file as a guide and it appears as a ghost layer behind your own notes — in the roll and in the score.

• Show guide and Hear guide toggle the ghost layer's visibility and sound; Hear take mutes or unmutes your own recording against it, and the guide can use its own instrument.
• Record against the guide: after a one-bar count-in the guide plays from the top while your playing is captured in sync — ideal for practising a part until it matches.
• Eject removes the guide and restores your previous settings.

Library

Your saved takes appear as chips below the transport — click one to load it, or delete the ones you no longer need. Each take remembers the instrument, key, grid, and time signature it was recorded with.