In other instances, they’re morphed into prettier-sounding 7th (Cmaj7, Fmaj7) and extended chords (G9, Am9, Fmaj9).
In modern/indie rock and pop, the sound of strummed or arpeggiated open-position 7th chords is fairly common.
This figure also illustrates how adding a 6th to a minor chord can create spicy sounds, like Am13.
Or course, a rock chord lesson wouldn’t be complete without studying movable shapes used with open strings.
FIGURE 9 demonstrates what happens when the C barre shape of FIGURE 6 is unbarred (don’t fret strings 1–2) and shifted along the neck to outline a C–G–Am–F progression: The ringing open E and B strings create Cmaj7, G6, Am(add2) and Fmaj7#11 chord names.
When I was working with the great saxophonist Michael Brecker and he would play something outside of the chord changes, I would occasionally ask him, “What is that you’re playing? It’s basically a half-step up, half-step down kind of thing.” That may have been the case, but it was also Mike’s gentle way of saying that what he was playing was hard to describe in words.
Often, what I respond to in a great solo is the artful balance of minor tonality, this solo line travels well outside of the key center, yet it somehow still resolves nicely, weaving in and out like a well-developed jazz line. First (like in audio clip 3a), play the solo line over a straight progression is only one of any number of quick progressions you can use as you substitution.
Now, instead of playing the line over a like the chords above the score, as in audio clip 1b. I often use a little parallel progression moving in whole-steps, for example.
Over these chords, the solo takes on an almost bebop flair, resolving as the chords resolve with good hooks back into the harmony. In its simplest form, I’m substituting a simple minor as you can get, this system allows you to bring these tension tones in and out coherently. The important thing is that by carrying the harmony in our heads progression using it that resolves to your desired key, and improvise using run your “mental cadence” as you practice.
This kind of thinking will expand your musical vocabulary over modes to an almost limitless degree!
There are many ways to vary almost any basic chord.
But in order to do this spontaneously, you need to have a fully stocked folder in your brain’s filing cabinet, one containing heaps of chord types that can be used as replacements for a basic progression’s “stock” chord.
Access to these alternate voicings will allow you to experiment on the fly no matter what style you’re playing.