iPad Music Software: Musix (App Store link) is a $4.99 app that turns an iPad into an isomorphic music controller.

An isomorphic keyboard is a musical input device consisting of a two-dimensional array of note-controlling elements (such as buttons or keys) on which any given sequence and/or combination of musical intervals has the “same shape” on the keyboard wherever it occurs – within a key, across keys, across octaves, and across tunings.

Description:

Each hexagon on the screen is a note, and surrounding hexagons are harmonically related.

Hexagonal isomorphic keyboards are defined by the harmonic relationship between the keys. You can define the relationship in two directions, say a major third and a minor third, and the third direction is the difference of these two intervals (in this case, a semitone).

Musix comes with a set of built-in layouts which use different harmonic relationships between the notes. Each layout has its own advantages and disadvantages. For example, the harmonic table layout allows you to play a major or minor chord with one finger, by touching at the intersection of any three hexagons. The Wicki-Hayden layout puts all the white keys together. Try them all and find one that works for you.

Musix has six real-time FM-synthized instrument sounds. No wavetables here. Each note sound is synthesized on-the-fly, meaning that you get the full richness of bass and brightness of treble that the ipad speaker or your headphones can generate.

You can change the size of the keys to fit your fingers and your dexterity – start practicing with epic-sized keys and as you get better you can make the keys smaller to give you more notes on the screen. Keyboard layouts are fully customizable – create your own isomorphic keyboard centred on any note.