Jazz Guitar Lesson: 2-5-1 in C - Chords

Peter, thanks for posting this, it really helps those of us who still struggling with basic jazz; Keep up the good work. CHEERS

gr8

The backing track is too loud.

Haha it would be a great name for him. Burt doesn't even sound like that

LOL

Robin Thicke - Lost Without You!... for the most part anyways. I never understood why the A7 works in substitution of the Am7. Still don't. Does anyone know why?

Because the C# has stronger harmonic movement to the root of the D minor chord than a C would in the Am7. An A7 really wants to resolve to that Dm chord because it's the 5 chord of D, and making that chord dominant creates a smoother resolution.

Ah. I got it. Another question though. Is that what you call secondary dominance? Making the key D in order to play the A7 and to have that C# in there for harmony?

Yes, pretty much. A secondary dominant is an "off key" dominant chord that resolves to a major or a minor (or dominant) chord that is a perfect fourth higher. In this case, the A7 is the "V of II", or the relative fifth degree of the D minor chord. In the key of C major, possible secondary dominants would be C7 (to F), D7 (to G), E7 (to Am), A7 (to Dm), and B7 (to Em). Diminished and half-diminished chords don't have secondary dominants.