# What is the name of a circular clock-like diagram in which you can place a triad shape and rotate it to get the notes in a chord of a particular type?

Not sure where I got this idea, but if you take your chromatic scale and wrap it in a circle, then draw a triangle, for example from A to C to E back to A, and rotate that triangle, it will show you the notes of another chord of the same type. It also works with extended chords and entire scales, like if you draw a star from each point ofthe major scale or one of the modes, you can visually see what notes belong to a scale or mode with a different root simply by rotating the shape.

Is there a name for this?

• Could that be just a circle of fifths? Like this one: en.wikipedia.org/wiki/File:Circle_of_fifths_deluxe_4.svg ? (It's not the same thing exactly but you can do all the things with inscribed shapes that you describe and it will work too. And it's useful in other ways too.) – Ramillies Nov 10 '17 at 12:32
• Well.. almost, but a Circle of Fifths unwound. If you trace the whole circle of fifths around it you get a dodecagon (12-pointed star). If you just label the natural notes, and/or add white and black circles (or whatever mark you chose) to mark the white keys on a piano, it also makes it real easy to relate or map the chord and scale shapes to a keyboard. I've only met one person who used this, and he didn't seem to know where he got the idea either. I've never heard or seen it mentioned by anyone with formal music training. – jdmayfield Nov 10 '17 at 17:22

Sounds like you are referring to the Tone Clock:

Peter Schat's 'Zodiac of the Hours', which graphically represents the tone-clock steerings of the twelve hours. Note that X can only be steered as a diminished seventh tetrachord (hence, the only non-triangular shape). Each point of a shape represents a pitch-class on the chromatic circle, and each shape represents one transposition or inversion of an hour.

• Awesome! @Stinkfoot, I've been trying to find this forever!! So cool. Besides mapping triads, you can also map extended chords like 7ths etc. I found a lot of things out this way long before being told or reading about it somewhere. Like the various 7th chords are basically two triads overlaid, that share 2 of their 3 notes, and that many chords with complicated names are just inversions of simpler, more common chords. You can even map out scales or whole songs geometrically within a key, or continuing outside. Made sense of a lot of things where the theory was verbally confusing. – jdmayfield Nov 11 '17 at 20:46
• @jdmayfield - I just found it a few days ago, so I guess it was fate. I was doing some research about jazz harmonica and came across that site where it's mentioned. I haven't spent much time with it yet, but the last tube I put up there is a lecture about its use. – Stinkfoot Nov 11 '17 at 22:17
• That's pretty awesome. I've found it helps a lot trying to understand how different instruments relate tk each other as well. Really, it's kind of an awesome map of the entire Chromatic Scale, where you can plot intrval paths between the notes for chords, polychords, scales, even entire songs that don't always fit into a little scale box or single key. So cool how you can transpose by taking a particular shape and rotate it and immediately see what notes in the transposition without doing any mental gymnastics. It's like a musical calculator, only it's just a diagram on a piece of paper! – jdmayfield Nov 12 '17 at 6:53

Oh hey, I made one of those not too long ago. I even prettied it up. I call it the Major Heptagon. I suppose I should go back and make a 12 tone version of it too.

Red is the tonic (is Major) and moving clockwise goes up the scale while counter-clockwise goes down. The green lines are 2nds/7ths, the gold lines are 3rds/6ths, the blue lines are 4ths and the red lines are 5ths. The spiked blue line is an augmented 4th while the spiked red line is a diminished 5th.

• Nice, @Tama. I have an easier time relating everything to Natural Minor, probably because I'm dyslexic and it's easier for me to think starting at A. I also use colors associated with the notes, so for me A is red. So the spectrum ROYGBIV is ABCDEFG, making the black keys in-between something like reddish-orange, lime-green, greenish-blue, purple, and reddish purple. If you make your 12-note clock with D at the top, and trace the diatonic scale skipping every other note (ie min and maj 3rds), you get a nice symetrical, rotatable view of all the Church Modes. – jdmayfield Nov 11 '17 at 20:59
• I don't really associate the colors with a particular key, ie red could be any note. I tend to think of natural minor as the major scale starting on 6. On my chromatic diagram I did make C red just because most theory is based on C. I also prefer the use of RGB/CYM since they're the purest forms of color; orange being the odd color out. It also doesn't matter much to me for it to be symmetrical since the scale itself is not built symmetrically. In short, this diagram is mostly for me to remember the intervals between all the notes. – Tama Nov 12 '17 at 1:21
• Ah, yes. I like to use the modes a lot, so more specifically, red for me is the Minor/Aeolian root, orange Locrian root, yellow Major/Ionian root and so forth. The in-between colors for blue notes or adjusted scale roots, like the 7th mode of Harmonic Minor (I forget the name). Actually Natural Minor is symetrical from beginning on the left to the right, the Dorian mode is symetrical from the root going left or right outward. If you play the modes using the same root note, changing to the next mode by order of fifths, you get a symetrical order of feeling from darkest to lightest... – jdmayfield Nov 12 '17 at 6:28
• e.g. keeping, let's say A as root, play Lydian, then Ionian, Mixolydian, Dorian, Aeolian, Phrygian, and Locrian, or the exact reverse. You will see that in that order you go from lightest feeling (Lydian) to the darkest (Locrian). Coincidentally, in conventional tonal music theory you are just going through the keys according to the Circle of Fifths/Fourths. But if you have a drone note in the background to keep your attention on the A (or whatever note you choose as long as it's the same) as root for all 7 modes, it's quite noticable. Also only one note changes at each modulation. – jdmayfield Nov 12 '17 at 6:40