Ascending/Descending Minor 3rds

[LiquidMidnight]

I've encountered this melodic technique before. My band is learning a new song and one part has a harmonized guitar part. My guitarists can program harmonized parts with his TC Electronics processor, but he needs to punch in the scale. The root of harmonized part is a succession of minor 3rds. It's similar to a whole-tone scale, but only using minor 3rds. Is this an actual scale? Another time I've encountered this was in the section of In Memory of Elizabeth Reed by the Allman's right before the second half of the song, if you know what I mean.

[mutedeity]

A succession of m3 intervals gives you a dim7 chord. Most people don't consider this to be a scale in it's own right, however it is part of Messiaen's modes of limited transposition and is a 3 transposition mode in this sense.

[LiquidMidnight]

Ahh, yes...I was just thinking that it probably creates a dim chord. Thanks for the info!

[MarkTAW]

Just because the roots move by minor thirds doesn't mean the chords built on top of them stick within those notes. I'm not familiar with this song at all, but I'd be surprised if there was a "pick from these scales and get the harmony" scale out there, at least, pre-programmed into the TC Electronics thing. It may take some work on your (or your guitarist's part) and it would probably be a decent exercise to figure out what might work there.

[cowsgomoo]

if you've got a harmonizer that adds a minor 3rd, diminished 5th and a double flat 7th, then yeah, you've got a diminished 7 chord (as the others have said)

it probably has limited music use, since you're limited to one ugly sounding chord moving up and down, but I can imagine being able to make some music out of sliding the root up and down a half or whole tone... this would use the notes of either the H-W diminished scale, or the W-H diminished scale

the best thing about a diminished 7 chord is the fact that it can be used to modulate in and out of some very diverse tonalities... if you lower any note of a diminished 7 chord by a half step, you get a dominant 7 chord on that note... so in the right context they can be gateway chords to all kinds of wonderful harmonic goodness

[DavidMP]

If I remember correctly there are only 3 independent dim7 chords (or tetrades) , the rest are inversions of one of the three, i.e. Cdim7=[C Eb Gb A], Ebdim7=[Eb Gb A C], Gbdim7=[Gb A C Eb] and Adim7=[A C Eb Gb] are one group, the others being B and Bb. This can make changes to different keys easier by virtue of the resolution mentioned above