Gentlemen, I really want to thank you for describing this mediant/tri-tone harmonic movement thing. That's very cool. I've looked at moving major and minor triads around before, but always struggled to make it sound good. Restricting the movement to thirds and tritones seems to be the ticket. I don't know why I never realized it before.
In case anybody still isn't getting it, here's a simple experiment I just did that blew my mind. First write a simple little melody of, say 4 bars. Pick a triad that fits the first couple notes. Then change to a new triad that fits the next couple notes, making sure to move the triad root only by a major or minor third or tri-tone, up or down. Keep going until the end of the phrase. Then revoice the chords for optimal voice leading.
Say the melody is Auld Lang Syne: C F E F A G F G. We can put the first three notes over Dmin. Then the next two will go under Bbmin (pretend it's a harmonic minor scale for the A). Then we have a problem for the next two notes: G-F. We don't want to go back to Dmin. Dmaj won't work, F#maj and F#min don't work (implies a scale including F-F#-G, and no such diatonic scale exists). Or we could jump by a tritone from Bbmin to Emin, but all of the options from there are rather dull. Bbmin to Emaj works, but it's a little too dissonant for the melody, and I don't like the options it leaves for the last note, G.
I think the best option is to go to Gmaj and then end on Ebmaj. It's not great, but it does have a nice atmospheric feel to it. And it sounds even better if you start with a melody that isn't strictly diatonic. There are other solutions to Auld Lang Syne, of course, but this demonstrates the concept. Play the chords as a pad in cellos and horns and give the melody to an oboe, and you've got a film cue.
Now I'm playing with fitting odd bass lines under the whole thing. Thanks again, this is really useful stuff.
In case anybody still isn't getting it, here's a simple experiment I just did that blew my mind. First write a simple little melody of, say 4 bars. Pick a triad that fits the first couple notes. Then change to a new triad that fits the next couple notes, making sure to move the triad root only by a major or minor third or tri-tone, up or down. Keep going until the end of the phrase. Then revoice the chords for optimal voice leading.
Say the melody is Auld Lang Syne: C F E F A G F G. We can put the first three notes over Dmin. Then the next two will go under Bbmin (pretend it's a harmonic minor scale for the A). Then we have a problem for the next two notes: G-F. We don't want to go back to Dmin. Dmaj won't work, F#maj and F#min don't work (implies a scale including F-F#-G, and no such diatonic scale exists). Or we could jump by a tritone from Bbmin to Emin, but all of the options from there are rather dull. Bbmin to Emaj works, but it's a little too dissonant for the melody, and I don't like the options it leaves for the last note, G.
I think the best option is to go to Gmaj and then end on Ebmaj. It's not great, but it does have a nice atmospheric feel to it. And it sounds even better if you start with a melody that isn't strictly diatonic. There are other solutions to Auld Lang Syne, of course, but this demonstrates the concept. Play the chords as a pad in cellos and horns and give the melody to an oboe, and you've got a film cue.
Now I'm playing with fitting odd bass lines under the whole thing. Thanks again, this is really useful stuff.