Influenced by the chord voicings employed by McCoy Tyner and the harmonic patterns used by John Coltrane, Justin Perdue began tuning his guitar in fourths (E-A-D-G-C-F, low to high) in 1990. Initially, this was intended as an experiment to explore that possibilities it opened up for more symmetrical scalar patterns and chord voicings than the conventional guitar tuning.

One of the immediate (and lasting) effects of this change is that standard bar chord voicings and open position chords are no longer workable options. As it turns out, many guitar cliches one takes for granted become significantly altered - making one realize that these phrases have become cliches due to how readily they fall under the fingers in conventional tuning — a convenience which is often not the case when tuning in fourths.

Read more of this post at Justin Perdue's myspace blog...