What does "isomorphic" mean?

Iso - same, morphic - shape.

Basically it uses a regular pattern of keys, instead of staggering keys into pentatonic and diatonic scales, like a piano does.

This makes it harder to "find" the diatonic scales, but easier to transpose between different keys.

You can see an example here: https://www.youtube.com/shorts/kMD1qXtDAdg

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mrob 2 hours ago | parent [-]

It's also easier to learn because there's one consistent mapping between notes on the page and the sound, instead of many different irregular mappings specified by "key signatures".

But traditional notation is more compact, and for music based around diatonic scales, implies information about the harmonic function of notes that could be useful for interpretation.

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TheOtherHobbes an hour ago | parent [-]

It's harder to learn because fingerings are based on key notes and transpositions around that.

If the key is G you don't start with your hand on C and move it up to G, you start on G and move it relative to that root.

This matters because over/under moves usually happen at certain scale points. So if you learn the scale you have good chance of defaulting to the most efficient movements with muscle memory.

If you're referencing everything to C you'll never understand the scales and their different fingering patterns.

Anyway, here's Martha Argerich playing Prokofiev's Toccata. (What happens around 3:14 may be illegal. But here we are.)

https://www.youtube.com/watch?v=v0fv5HKYn7k

	▲	mrob an hour ago \| parent [-]
		But on an isomorphic keyboard you can just move your hand up or down and use the exact same fingering. You only have to learn how to play the scale once, not a different way for each key. You don't reference it to "C", you reference it to the first degree of the scale, and the key doesn't matter. IMO, the traditional keyboard has been obsolete ever since the Jankó keyboard was invented: https://en.wikipedia.org/wiki/Jank%C3%B3_keyboard