Connect your E-piano or keyboard to your computer or tablet with a USB cable — Klavissimo then hears every key, every touch and every pedal, live.
Plug in the USB cable
Plug your instrument in via USB — most E-pianos and keyboards support it. Another program that's already holding MIDI open (a DAW, say) can sometimes block access.
Allow the browser permission
The first time round, the browser asks for permission to access MIDI devices — confirm it. Web MIDI works most reliably in Chrome and Edge; Safari can't connect an instrument.
Check the connection
A chip at the top of the app shows the status: "Connected: your device name" turns green the moment Klavissimo detects your instrument. With nothing plugged in it reads "No instrument" — and the on-screen keyboard steps in instead.
Without a cable “No instrument”, plugged in it turns green “Connected” — and pull the cable and it honestly says “Disconnected”.
Good to know:
Got an acoustic piano? Then you can skip this whole chapter — "Real piano" in your profile needs no cable at all. And with no instrument handy, "No piano yet" turns the on-screen keyboard into your instrument, scored just like a real key press.