The tool every musician needs, and almost nobody explains properly
Rotate the circle. Tap a key. Hear exactly what the theory sounds like. Scales, chords, staff notation, and a playable piano keyboard. All in one place.
What's inside
Rotate through all twelve keys. Each position shows the key signature, the relative minor, and all the notes laid out with no clutter.
See the full scale on a piano keyboard with every note labelled. The scale plays automatically so you hear the character of the key straight away.
Every diatonic chord shown in staff notation with its name and Roman numeral. Tap any chord to hear it played.
Clean staff notation throughout, with the correct key signature including all sharps or flats. Reinforce what you're reading with what you're hearing.
An interactive keyboard lets you play individual notes, the full scale, or any chord. Notes highlight as they play so you can follow along visually.
All seven modes, Ionian through Locrian, across all twelve keys. Each mode has its own colour so switching between them is instant.
In use
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"Twelve keys in a circle, each a perfect fifth from its neighbour. From Bach to the Beatles, composers have used this instinctively for centuries."
Works equally well on both. The layout adapts cleanly to either screen, designed to be picked up for thirty seconds or thirty minutes, whether you're checking a chord at the piano or working through a key from scratch.