As expected, your course has lead me down the road to a greater understanding of music theory and the inter-relationship between roots and fifths. Can you take a moment to explain the chart showing this relationship? I have be able to understand most of it on my own, but I wanted to hear you explain it so that I am not misinterpreting what I am trying to work out on my own.
I know this chart relates to diatonic chord progressions. It is suppose to show the complete inter-relationship of musical notes and intervals. If I am reading this correctly, if you move clockwise, the circle rotates in 5ths (V) ie: the 5th (V) of the C is G. If you move counterclockwise, we are moving in the direction of 4ths (IVth) ie: the I4th (Vth) of a C is an F. The same is true for the minor scale shown below. The inner minor circle seems to link the Major key to the 6th (vi) ie in the key of C the 6th (vi) is a Am and so on. Now this is where things get a little funky. If I move from the C, down diagonally to the left, I get a ii or Dm. Likewise, if I move down from the C to the right, I get the Em or iii. If any of this is true, (and it seems to be) there is a lot more here than just a “circle of fifths”. Also, I don’t know what role the diminished seventh plays in all of this.
I love your course, and have reviewed some of the lessons several times. However, because I had a musical background, I seem to want to take your course material and run with it. I stumbled on the Circle of Fifths sometime ago after finishing your module on fifths., thirds and sevenths. I am just now trying to wrap my head around this. Any help or suggestions you have would be greatly appreciated. Maybe this would make a great course topic?
I suppose you could try to glean data about diatonic chord progression here, but this is more about keys than chords. That’s why there’s no diminished seventh chord anywhere - the major/minor designations aren’t talking about chords (primarily at least).
The only big thing that’s missing from our discussion so far is the helpful role this chart can play in remembering key signatures -which are missing from this version of the chart. Here’s one with more data (and more colors )
relative minor/major keys share a key signature (i.e. C major and A minor, same notes, same key signature)
You can also see how different interval movements will affect key signature. For example, if you skip one key and go from C to D, which is a whole step, you add two sharps (or if you jump back to Bb, you get two flats). So you can file that away and know that any time a song modulates up a whole step, for example, there will be two notes that change from the previous key.
@Gio, anything to add? Curious if you ever use the circle to talk about chord progressions like Brian was talking about, I’d actually never heard of it being used like that.
I haven’t used the circle to talk about chord progressions the way you were with the ii and iii chord, @bsickels. The chord progression magic happens when you watch root movement around the circle of fourths (or, as the classical cats call it, falling fifths) - but it isn’t key signature or chord quality relevant - it’s only root relationships.
(as in iii-vi-ii-V-I … in whatever key, it’s moving in fourths the entire time, the chord quality changing to fit the key you’re in)
The closeness of the ii and iii seems like happy coincidence. If it’s helpful, awesome. But I don’t think it fits in to much application or practice that I’ve run across.
I did this sketch to try and illustrate a little better how the circle of fifths works.
Unfortunately it hasn’t scanned too well, but hopefully it will still help anbody who is struggling to get their head around it.
As an example, if you take the C scale in the illustration, and then look at the F scale and G scale on the inner ring, you can see that the first 4 notes of the C major scale are the last 4 notes of the F major scale, and the last 4 notes of the C major scale are the first 4 notes of the G major scale.
Also notice that if you pick any of the major scales (on the inner or outer ring) both of it’s linked scales only have 1 note that is different.
Using C again as an example, F major scale has B flat and G major scale has F sharp.
This applies to each and every major scale - the scale next to it in either direction only has 1 note that is different. That is why they are the next scale. They are most harmonious, because they are almost identical, because all except for 1 of the notes are the same.
The lightbulb moment for me, was in understanding that the keys overlap starting, from the fifth note, in this way.
Very cool to dig into this like you do! And there is something awesome in exploring the “symmetries” here and the mathematical connection between geometry and harmony.
I guess this is another way of saying “as you move away from C, either clockwise or counterclockwise, the key signatures incrementally acquire one more sharp of flat, respectively”
I think I know what you mean, but saying “most harmonious” is also a bit fuzzy here… It is probably partly because you shouldn’t compare the scales, but the chords derived from one scale! So, if you center everything around C for starters, and then look at the chords derived from the C major scale, then you find that, indeed, the F major chord is there and the G major chord is there, but NOT the D major chord, Bb major chord etc. That is because the latter are not diatonically related to the C major scale, whereas the former are.
There is so much to explore and understand - your epiphany about the “overlapping” scales is pretty cool though
No it isn’t. Not at all. If one is playing a simple 3 chord song and the the key chord is ‘C’, then the most likely next chord will either be an ‘F’ or a ‘G’ - because they are the most harmonious, because they are built from a scale that has the most similar group of notes, and they are linked by 5th’s in either direction.
You could go on to argue all you want about relative minor keys, and 2/5/1 progressions etc, but if you could bet on it at the gambling shop (which would be the next most likely chord played after ‘C’) then the clear winners more often times than not, would be F and G - and most likely in that order.
Ditto for any other chord/scale around the circle.
Incidentally, if you were in fact playing in the relative minor key of A minor, then the safest bets at the gambling shop for most likely next chord, would be D minor and E minor. In that order, and for the exact same reasons.
Epiphany lol - nice word for it, but that’s the main point. They do overlap - from the 5th note. Hence why it is called The Circle of Fifths.
Other pictures of the circle of fifths don’t illustrate in the same way - that’s why I drew the picture as soon as I understood what was going on.
It’s just a shame the blue I used on the inner ring doesn’t show up very well.
I’m also all for simplicity, and that is the simplest pictorial representation I can think of.
I cannot count the number of times I have used this chart over the years.
Everything from scales to chords to chord progressions and inversions etc. etc. etc.
Initially I made the chart over 30 years ago because once you get into the reaIm of 5 6 and 7 sharps, and flats, most charts do not show all of the key signature names. As a matter of fact the chart Josh posted is the only one I have seen recently that also shows them all. Even the OP chart does not show all of them.