Circle of Fifths Guitar
The circle of fifths is a geometrical representation of key signatures used in writing traditional musical notation. For modern guitar players interested in developing a working knowledge of music theory that can be applied specifically to the fretboard the circle of fifths is less useful. But if you insist on exploring the idea you can easily map out the fifth cycle on the guitar neck with patterns.
Guitar players can play the circle of fifths by using two types of fretboard movement. Starting at any fret on string 6 a fifth interval can be played by moving over one string and up two frets. Starting at any fret on string 5 a fifth interval can be played by moving to string 6 and remaining in the same fret. Let’s use these two types of guitar intervals to complete the fifth cycle on the neck. You can start in any key but I’ll begin with the key of F beginning at the 1st fret of string 6.
The 5th from F is C.
The 5th from C is G.
The 5th from G is D.
The 5th from D is A.
The 5th from A is E.
Continue this process until you’ve cycled through all keys. Reverse it to produce the circle of fourths.
You can hear a chord progression based on this type of movement in the song “Hey Joe” by Jimi Hendrix. The verse progression is all fifths starting on C.
C G D A E
I should point out here that rather than try to follow each key change with a new parent major scale, Hendrix simply played the E minor pentatonic scale over the whole progression for the lead guitar solo. This works because the E minor pentatonic notes are all found in the same keys that also have the chords. The exception is the E major chord. In its case the minor pentatonic gives the major chord a blues flavor.
So the circle of fifths and the circle of fourths don’t have a whole lot of practical use in music theory for guitar. And if you map out fifth intervals properly on the fret board then you already have the concept down.