The amount of confusion I see among guitarists concerning the Key Circle is massive. Here’s one reason why:
If you google “Key Circle” and click on “Images” this is what you’ll see:
As can be inferred from all these images, the Key Circle is very deep and has multiple functions (see, The Key Circle, Giant Steps and Physics), however, I want to focus on one aspect:
Every single google image in the screenshot above calls it a “Circle of 5ths.”
If you start at the top (C) and move clockwise it is indeed a Circle of 5ths.
However, if you move counterclockwise it is a Circle of 4ths:
So why is it called “the Circle of 5ths” in every single instance in the Google results above instead of “the Circle of 4ths?”
Well, there are many reasons. Some have to do with ascertaining key signatures, &/or perhaps because the interval of a 5th is the most consonant (after the octave) because of, well, physics; it’s the first interval after the octave in the harmonic overtone series…blah, blah, blah.
When it comes to your typical, self-taught guitar player, understanding key signatures, reading music, the harmonic overtone series and any number of other functions for the Key Circle are abstract, irrelevant and shrouded in mystery because of the nature of the guitar. It’s a non-linear instrument and therefore it’s confusing to apply the mathematics and logic of music to it.
Gross overgeneralization here: Guitar players are notoriously musically illiterate; they don’t understand music theory, chord construction, diatonic harmony and modes. They can’t read music and so have developed their own written tablature that no one else understands or uses. They play by pattern and rote without understanding what they’re doing. I’ve ranted about this before in Inbred Guitar Culture.
All this and more is why guitarists find the Key Circle confusing and irrelevant.
I’d like to rectify that situation. It’s not complicated. Applying the Key Circle to the guitar begins with assigning its primary function as being a cycle of 4ths rather than a cycle of 5ths. That is the key to unlocking your understanding of the guitar neck.
Why? Because the guitar is tuned in 4ths.
The first thing I have students do is use the Circle of 4ths (follow the arrows) as a mechanism to memorize the names and locations of 12 notes (13 counting "C" twice) on the 6th and 5th strings:
Then, through a pattern of octaves, these 12 notes are extrapolated out to the entirety of the guitar neck. I also use the Circle of 4ths to ensure that everything is practiced in every key.
If what I've said piques your interest, you can download my 5-Lesson Foundational Series for free with no obligation or commitment and see for yourself:
Now, it's just as easy and valid to use the Circle of 5ths for the same purpose. Here's an example of a guitar teacher doing just that; using the Circle of 5ths and a pattern of octaves to locate every note everywhere on the guitar neck, as well as using the Circle of 5ths to practice in every key. As far as that goes, we are similar. Six of one and a half-dozen of the other.
So why then do I insist that using a Circle of 4ths is better?
The guitar is tuned in 4ths, not 5ths.
If you move in 5ths the keys are: C G D A E B F# C# G# D# A# E#(F).
The Circle of 5ths causes sharps (F#, C# etc) thus perpetuating a guitar-centric default (see Inbred Guitar Culture). The guitar naturally sounds better in sharp keys - G, D, A, E etc. - because of the tuning of the open strings (which are the most resonant) but I guarantee you that flat keys are more common, especially when it comes to R&B, Pop and Standards. Most other instrumentalists (keyboards, saxes, trumpets etc.) think in terms of flat keys, i.e. Bb as opposed to A#.
The tune most often used to demonstrate a Cycle of 5ths is "Hey Joe." The chord progression of "Hey Joe" is, C G D A E; a Cycle of 5ths. Are there any others? Probably, but I can't think of any off the top of my head.
3. If you move in 4ths the keys are:
C F Bb Eb Ab Db Gb B E A D G.
Are there any songs that use cycles of 4ths? How ‘bout any tune that uses II-V-I, which is a cycle of 4ths. How about gazillions of standards like Autumn Leaves, All the Things You Are, How High the Moon, Solar, Tune Up, In Your Own Sweet Way, I Got Rhythm, Bluesette, etc, etc, etc....
In Pop you’ve got After the Love is Gone by Earth, Wind and Fire, Europa by Santana, I Will Survive by Gloria Gaynor; I could go on for days - in almost every genre.
Cycles of 4ths are waaaay more common in music than Cycles of 5ths. So why not drill that way?
To drill in 5ths is training your muscle-memory, training your ear and programming your brain to execute a movement that doesn't occur in music near as much as 4ths. It's inefficient. It’s a lot of work for not much return.
In the link I gave above of a guitar teacher using the Circle of 5ths much like I use the Circle of 4ths, he talked about "going backwards" to get the Circle of 4ths.
I would argue the opposite. I am not alone in this. My teacher, who was not a guitarist (he was a Jazz pianist and arranger), called moving in 5ths, "backcycling."
When he said to drill something "around the Circle" or when he said, "cyclical movement" he meant the Circle of 4ths; that was the default.
So in my opinion it just doesn't make sense to drill in 5ths rather than 4ths per the reasons given above.
“...the way you lay out the circle of 4ths on the guitar neck is a new revelation to me and I've been searching for this sort of stuff for four years online! I've spent the last 2 weeks practicing the stuff in the free lessons and have enjoyed it on a daily basis. Already familiar with some of the scale fingerings and found the key cycle a brilliant way to run them all! Very smartly laid out and easy to put one thing on top of the other. Feels like very little wasted time practicing and I can't tell you how much I appreciate that!” -Frank DiNuzzo
“I have been puzzled about the fretboard for decades! Thank you for the most intelligent approach to teaching guitar I have ever encountered! I was astounded to follow your lessons and reasoning, and find that all of a sudden I could see the fretboard as something intelligible and not as a jumbled mess! I know the circle of fifths because of piano but had never looked at the other way as a circle of fourths and how to apply that to the fretboard! Who teaches that??? Only you!” -Vickie Bliss
I’ve taken 3 of your 5 free online lessons and plan on taking the other two...I’ve learned more in those 3 lessons than many hours on YouTube. They’re really good." -Bill Foster
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