For instance, look at Ex. 1. The basic progression—A, D, and E—is easy to play with simple chord grips. But suppose you have several songs in your repertoire with these chords, or perhaps you’re picking these changes alongside another guitarist. In either case, for the sake of variety you’ll want alternatives to the standard-issue voicings. Using a capo, it’s easy to find fresh pathways through familiar changes and, in the process, gain access to chimey open strings and controlled, bell-like dissonances that would be impossible to produce with barre chords.

Clamp your capo at the 5th fret and try this two-bar passage. As you work your way through the arpeggios, keep as many open strings sustaining as possible (that’s the meaning of let ring below the treble clef). Notice the tangy seconds that sometimes emerge as a result of two adjacent strings ringing together. In bar 1, D and E form a jangly major second as you ascend and descend the A and D arpeggios. This controlled dissonance gets even more robust in bar 2, when you create minor seconds by plucking G# and A on adjacent strings. Thanks to the capo, the fingerings are simple, yet the harmony is sophisticated.

A capo always offers several ways to interpret the same set of chords. In Ex. 2, move your capo to the 2nd fret and listen to yet another take on the basic A, D, and E progression. In bar 1, beats three and four, the pull-off yields a shimmering Dmaj7 chord. In bar 2, the open strings offer a subtle add4 and add2 harmony, in which the fourth and second degrees of the E major scale (A and F#, respectively) rub shoulders with notes from an E major triad. Suddenly your guitar sounds a lot like a harp. With practice, you’ll find yourself crafting colorful guitar orchestrations using only a capo and a little imagination.

Next time: Getting a grip on essential rhythms.