A New Sound from Harmonic Minor
While noodling around in the practice room today, I discovered a new (to me) application for a Harmonic Minor mode. I'm sure I'm not absolutely the first person to spot this, but I got some good sounds out of it so I thought I'd note it here, especially as I also stumbled across an exotic scale in the process.
If you know your Harmonic Minor modes, you'll know one of them is the same as Lydian with a #2 (#9), which I use a lot to give a nice bluesy sound over IV chords. Usually it's spelled 1 #2 3 #4 5 6 7, emphasising that 1 3 5 7 are the chord tones (a major seventh chord) and #2 #4 6 are the tensions.
But I accidentally stumbled across a respelling when trying this scale over a minor chord. In that case you could spell it 1 b3 b4 #4 5 6 7; the chord tones are 1 b3 5 7, a minor-major seven chord. The tensions are b4, #4 and 6. If you add the 1 back into these you have, in the key of C, the notes C E F# A, which is an F#m7b5 chord.
(I should say here that I'm slightly obsessed with the b4 on a minor chord. It's such an awful sound, but it can sound amazing if you hit it just right. So every once in a while I try to build lines that maximise the amazing and minimize the awful.)
So one thing to try is arpeggiating F#m7b5 as a set of tension notes over Cm7, resolving to the underlying chord tones of course. But you can also just run the scale, whish is C Lydian #9 or, if you must, E Harmonic Minor (but don't think about it that way!).
The great thing about this sound is that it contains the b4, which is a really fun and awkward note over a minor chord. You really have to work on your lines to avoid creating bluesy lines that imply a major tonality with the #9 as the tension note.
While playing around with this I sometimes went to the wrong arpeggio, grabbing Em7 instead. It turned out I liked that sound too. Analysing it out, the chord tones are C Eb G Bb and the arpeggio being superimposed is E G B D. The resulting scale is C D Eb E G Bb B. Numerically, this is most naturally spelled as 1 2 b3 bb4 5 #6 7.
This is Varunapriya b4, a mode of Yagapriya (see p.246-7 of the Encyclopedia). That's a pretty far out scale, and my notes about it in the book make no reference to this curious application.
I'll be experimenting with 3m7 and #4m7b5 on minor chords for a while to see if I can get some lines from these into my playing.
And those two chords? E G B D + F# A C E = G major. So in another sense, I'm sitting her eplaying C Lydian over Cm7. What I described above might seem like a very roundabout way to get there, but Lydian on a minor chord isn't the kind of place you visit just by rolling up to the front door...