Watch the Maj. Triad: Alt. Dom. Sound online guitar lesson by Kenny Wessel from Shades of Jazz
This section will focus on playing major triads over altered dominant seventh chords. Using triads, which are small, movable, recognizable cells, can be a great way to enhance our playing and improvising. We can start this process by seeing what triads are available to us. Lets start with a G7 shell (root, 3 and b7) and see what tensions we get by generating all 12 major triads over this key. (You can do this systemically, building a triad from the root, up a half step, a whole step, and so on, chromatically up the whole chromatic scale.) There are a number of triads that will work nicely over dominant sounds. For instance, an Ab major triad over a G gives us b9, 11, b13; a Db major triad over a G7 gives us b5, b7, b9; I particularly like the E major (up a major 6th) over the G7 which gives us these tensions: b9, 13, 3. Explore this process for yourself to see what chord tones and upper intervals are present in the triad and you can find your own sounds and preferences (doesn't have to be over just dominant chords, by the way). For this next section, we're going to delve a bit deeper into the sound of the E major triad over the G7 chord, that's a triad built a major sixth up from the root of the dominant chord.