Has anyone heard of the harmonic wheel? I wanted to paint a circle of fifths as a “cheat sheet” of sorts, to put on my piano, but then I stumbled upon a fascinating image. This one:

I’m a sucker for charts and symbols especially when it comes to music so I investigated further. Turns out it is a variation on the concept of the circle of fifths, only it contains a massive amount of information and it is intended to be used as a tool for composition. Apparently, this is the invention of a Spanish tutor and he has sold copies of the wheel on Amazon for a while, but they are out of print. Or so I believe. I wrote the guy asking if he had any for sale but didn’t get an answer. So I just went ahead and made my own //
I’m still figuring out how to use it, but it’s such a useful tool. Over the past years I have been scribbling notes and charts and overviews of music theory in little notebooks, scraps of paper, digital notebooks, folders on my pc and so forth, but it looks like all I will ever want to know about music is hidden in patterns on the harmonic wheel

It’s pretty cool.
Structurally, it is nothing more than five nesting circles of fifths, with an offset of 90° clockwise from the outside to the inside. The resulting positions gives information about scales, chords, chord functions and all the usual, essential stuff I keep forgetting. You need to remember the patterns but as a visual artist myself, my brain is wired to respond to shapes and colors.
This is the shape of a major scale. Just one position to the left and two positions to the right, and one circle outward contains all the notes you need.
But it also gives you the notes of all the triads and fourth chords in that scale.
These are the shapes for C-7, CMaj7 and C7:
And of course, you can apply these shapes to any note by just rotating the wheel. What I find most gratifying is the way you can easlily see the relation between chords that have overlapping notes. Jumping from a G-7 to a EbMaj for example is just changing one note, but that’s not something I come up with on an ordinary day. On this wheel it very easy to make these jumps and see interesting movements and progressions.
Colors / Synesthesia
Warning: esoterica ahead
It was also a lot of fun drawing this thing but there was one challenge that I spent quite a bit of time on: deciding what colors to use for the notes. This is not at all part of the harmonic wheel, but it was part of my original idea to make the cheat sheet. In order to facilitate learning (both for myself and my four year old son) I’m interested in the concept of synesthesia. My synesthetic experience is not well developed, but I believe it is something we can train, especially starting on an early age. Colors and musical notes are just vibrations and frequencies after all, so it’s easy to see how they can correlate. But since I’m not particular opinionated about the topic, I just had to do some research. Turns out people have been assigning colors to notes (and vice versa) for a long time.

Scriabin is very well known for this, but he was also a little bit of an odd one out, assigning colors based on the positions of the notes in the circle of fifths, rather than ascending or descending pitch. After pondering about the subject for a bit I decided to take my cues from a completely other field of study, namely that of the chakra system. The rationale being that these have been assigned colors for a very long time, on top of their correlation with musical notes. In the basic chakra system there are seven energy centers so it all maps out perfectly to a diatonic scale. I even read one particular book that mapped these notes very specifically to the energy centers of the body in both the diatonic scale and the chromatic 12 twelve note scale. Anyway, that’s just a side note.
I did my best to map these colors to the twelve notes and also went ahead and color coded my keystep. It looks like a toy now but hey, real men let go when it fits to the music.
What do you all think? Are you using a tool like this one, do you have synesthetic experiences? Do the color match your own set? Are there any other diagrams that I want to know about?
By the way
the website of the guy who invented the wheel is down (it went offline just as I started my investigations). There is a spanish version but it doesn’t have all the explanations like it did on the English site. And on YouTube there is a series dedicated to the wheel (also in Spanish). I watched it and it is very instructive, but also very dry indeed.