Comping: So What?
(scroll down for video)
Okay, so you’re at a jam and they want to play “So What”. Everybody knows that one, right? A-A-B-A form, yeah, yada yada, 8-bar sections, A sections in D dorian, B section in Eb dorian, bass player’s got the melody... and you’re going to play the Famous “So What” chords as a response to the melody. “Ba-dum-ba-dum-ba-dum-de DUMMMM...(chord, chord)”.
All well and good... until the soloing starts. Then you realize that 16 bars is a long time to spend on D minor. What to do? If all you have in your bag o’ tricks is the Famous “So What” Chord and the Dm7 voicing the Doobie Brothers used and a six-string barre chord at the 10th fret, you just might be in for a long night. Lucky you; I’ve got some suggestions to get your personal voicing collection jump-started.
Let’s begin with the Famous “So What” Chord. It’s a nifty mixture of perfect fourths with a third on top. All the notes are in the D Dorian scale. What if we took that voicing and just walked it through the Dorian scale? We could keep it on the same group of strings, start on the lowest possible note and walk it up the scale for an octave or so. Each note on each string would just move up to the next available note in the scale. While we’re at it, let’s also do it with the lowest voice removed – sometimes four-note voicings are more useful than five-note voicings.
That would look like this:
Some of those sounds you’ll like; some you may not like. But they’re all possible in the D Dorian scale and could be used for comping once you get ‘em under your fingers and in your ears. [Don't forget: Eb Dorian is only a half-step away. Everything we're doing here for D Dorian can be used one fret up for the Ebm 'B' section of "So What".]
Now how about looking at voicings made up entirely of fourths? If we start walking fourths around in the Dorian scale, we soon discover that not all fourths are perfect fourths – some of the fourths in that scale are augmented fourths (tritones). That’s okay; I never met an interval I didn’t like. Let’s do three-note quartal (fourth-based) voicings in D Dorian. Then, just as we can do with “normal” triads, we’ll invert them, putting each note in the chord on the bottom. Then we will wind up with three-note voicings that contain a fourth (perfect or augmented) and a second (major or minor). And again, it’ll all be stuff we could use for comping in D Dorian:
We could also do four-note voicings the same way. I did them on two different string groups to show you how that can be done. Then I did a set of inversions to get you started:
Next, we could take another very common guitar voicing that’s often used to suggest Dm6/9 or G13, among other chords. Then we could subject it to the same treatment, moving it through the Dorian scale. These voicings might be very tough to invert; some would be unfingerable (unless your name is Peter Mazza – if you haven’t heard him play, go listen and come back after you pick your jaw up off the floor!). But the point of all this tomfoolery is to expose ourselves to new sounds. While playing around with inversions, I came up with a couple of nice ones employing open strings, so my fingers remained unbroken. Here are the results of the experiment:
Last but certainly not least, there’s pentatonic harmony. If you’ve been keeping up with my web and video lessons, you should know that there are three minor pentatonic scales that are consonant with D minor/ D Dorian: D minor, E minor and A minor. So let’s harmonize all three of those pentatonic scales starting with their tonic triads in root position. We’ll get a nice combination of “normal” triads and quartal triads. If you start with the tonic triads in root position, you get inverted quartal triads. Starting with a first-inversion tonic triad gives you stacks of fourths for your quartal triads... but you’re going to do the other ones on your own now that I’ve shown you how, aren’t you? I would feel SOOOOO guilty if I robbed you of the thrill of discovery.

In this video, I actually use some of all this stuff while comping a couple of choruses of "So What". I also use some things we haven't discussed, such as inverted pedal point: keeping the highest note in a voicing static while I move the bottom voices around chromatically. (This happens around 12:57 in the video.) There are a few places in which I use rootless triadic "normal" voicings that imply moving from Dm7 to G7, which are both chords from the D Dorian scale. Sometimes, there are chromatic "approach" chords – I'm sneaking up on the chord I really want to play from a fret above or below. And I decided to end with a quartal voicing from the D melodic minor scale, just for a bit of ear-tweakage at the end.
It should also be mentioned that you can perform this process on any chord from any scale! My students learn to do this with major, minor (especially melodic minor) and pentatonic scales, among others. It’s a lot of work, but it’s musically rewarding!