For BiaB, sus2 and 2 are the same (root+2nd+5th). Basically, like a sus4 but replacing the 3rd with the 2nd of the scale instead of the 4th. If you enter Csus2 BiaB will simplify it to C2 instead.

The add2 adds the 2nd to the chord, but leaves the 3rd in place (root+2nd+3rd+5th).

That's the theory, anyway. Who knows what a style actually plays, especially if it's a Realtrack.

For example, there are a number of piano Realtracks that don't play sus4 chords when requested. I'm not sure what they're playing (my ear isn't well trained). I'm sure they're great jazz substitutions, but they aren't the chord I need, so I can't use these otherwise lovely tracks. frown

-- David Cuny
My virtual singer development blog

Vocal control, you say. Never heard of it. Is that some kind of ProTools thing?