ScottYee, I’ve been reading your many threads on this subject, and one thing has been puzzling me: why does it matter with an arranger keyboard? I know why it would matter with a regular piano or synth, where the notes you hear are exactly the notes you play, no more and no less.

But why does it matter when you’re playing styles? I mean, even if you don’t play the root using the left-hand chord, won’t the style itself play the root once it has detected the chord as the type you desire? Of course it will in the Bass track, but you can turn that off in most keyboards. But what about the Chord, Pad, Phrase, etc. tracks? Won’t the Root be included in them, too, whether you play it or not? And if you turn all of them off, then all you have is the Drums, which rather defeats the whole point of chord recognition and Styles at all!

This interests me greatly, since I’m working with some people on restoring true Just Intonation to music, which has been almost lost from Western music (except for a capella vocals and certain chamber string quartets) for over three centuries now. Modern microprocessor technology makes it feasible for the first time in history. But it would require very accurate chord type detection. For instance, while the 9th would indeed be the same as the Major 2nd, the 11th would not be the same note as a Perfect (Suspended) 4th (nor is it even in the heavily-compromised Even/Equal Tempered Scale we’ve been stuck with all these centuries -- a proper ET 11th would be the IV# note, not the IV note, but in JI it would be very flat of that, almost halfway to the IV). Likewise, the 13th and the Major 7th are not equals (in fact, the 13th is closer to the minor 6th!). Indeed, the Dominant 7th and Minor 7th are two different notes (and neither matches the Melodic Minor 7th), as are the Major 6th and Diminished 7th, or the Augmented 5th and Minor 6th (and 13th, for that matter), or the Diminished 5th and the 11th and the Tritone. Getting a computer to recognize all of these off of a standard 12-note-per-octave keyboard, in real time, is going to be tricky.