Tap a square to put a sound on that step. Drag along a row to paint. Tap a Bass or Bells square again to climb the scale. Tap a row's name to hear it.
Tap or drag notes and rests into the bar. Tap one in the bar to take it out. A full bar plays by itself.
Tap the string to pluck it. Drag the bridge (the bright post) to make the string shorter. The waves at the bottom compare your string with the whole string.
Every sound here is made live by the computer. Tap squares to build a drum beat, then speed it up or slow it down.
Then fill a bar with notes and watch the fractions add up to one, and halve a string to hear a note jump up.