So imagine you have selected a chord progression and a key in scaler, and want to play along with it and have no theory knowledge. Imagine a scale-key lock that does the following.
As each chord in the progression is played, the mapping of the midi changes such that the root note of the chord is put on a particular white key ( let’s say C3, for example), the next highest note in the chord is placed on the next white key (D3), the third note on the next white key, until the chord notes are exhausted. The remaining white keys in the octave are then allocated the remaining notes in the selected key.
On the black keys, you map the chords in the following way. The most recent or ‘current’ chord is mapped to the first black key (C3 sharp). But each time a chord is played, it shuffles down the black keys. So the prior chord in the progression is on D3 sharp, the one before that on F3 sharp, and so on. Hence the 5 black notes in the octave play the current chord and the four prior to it.
Now imagine that mapping above is repeated up and down the octaves of the keyboard, with all the mappings simply shifted by an octave as they change, so the mapping is not restricted to any specific subset of the keyboard.
As your chord progression plays, you can now jam along knowing that you will always be in key, have quick access to the recent chords on the black keys, and knowledge of how the white keys will relate to the chord.
If you want, you can now program arpeggios, melodies, or whatever as midi input in your DAW and then change the basic chord progression and your “solo” will follow.
I have been able to set up something very similar to this using Scaler a plugin called Melodic Flow and some midi utilities in Cubase. But it takes a lot of work and sending of transformed midi between tracks. Would be great if Scaler could do the work.
Finally: you might want one instance of Scaler to deal with and play the chord progression, and another to deal with the midi remapping I have described here so you can jam along with it. It would be great to be able to link instances of Scaler for this purpose with changes in the chord progression reflected in both instances in real time. I made a request for that linking of multiple instances a while ago.