this is just a checkup:

say we are playing in A major:
if i play B Dorian, then will i still get the ionian (major) sound, or the jazzy dorian?

over the same A major progression:
If i play the Ionian on B, instead of A, will I get the happy ionian sound, or the more jazzier dorian? (Although playing the Ionian fingering)

Just osme quick help would be greatly appreciated!!!

Thanks
Slasha

It depends on the progression.

If you were playing a progression that had an A major(ish) chord as the root chord it wouldn't matter if you played B dorian because A would still be the root note. If would sound wrong if you tried to resolve to the B because the whole progression would tend to resolve back to the starting chord of A. If you want to get a jazzy sound in B Dorian, start your progression on a B minor (7th) chord.

As for playing B Ionian over A major, a car crash is coming up. You might manage to pull it off if you play B mixolydian, but the 7th in B Ionian is A#, which would mean you would have A as the root note of the chord, A# as the 7th, and B as the scale resolution note. Ouch. To get the jazz sound, play the min7 (like Christoph ssaid), but then move to, say, the domV chord, so it sounds jazzy, rather than moving to another minor.

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