Why Blues Guitar Actually Has 3 Key Centers (Most Players Miss This)

[00:00:00]Now, does a major blues come from one key or three keys? Well, if you want to understand this, just hang out to find out.

[00:00:10]Now, a major blues, let's take G, right?

[00:00:13]Would be G7, C7, and D7. These are the one, the four, and the five chords. But, the key of G contains these chords: G major 7th, A minor 7th, B minor 7th, C major 7th, D7, E minor 7th, F sharp minor 7 flat 5. Now, you'll notice that the one chord is G major 7.

[00:00:34]The four chord is C major 7, and the five chord is D7. It's not G7, C7, D7. Those chords don't all come from the key of G major.

[00:00:46]Only one of them does, right? This creates a bit of a problem and a and sort of cool problem in the blues, okay?

[00:00:52]Now, this G7 chord, where does that come from? G7, if we play it like this, comes from the key of C. It doesn't come from the key of G, okay? The G7 comes from a totally different key. Now, where does C7 come from? C7 comes from the key of F. D7 comes from key of G. So, these three chords, the G7, C7, and D7, come from three different keys. Hence me saying at the start, is the blues in three keys or is it in one key? So, if we look at it in one way, we can almost say it's like three separate keys, and we're doing a key change every time we change chords. But, that's not quite right, okay? Because if we think of the chords as just let's not think of them as seventh chords. Let's just think of them as major chords: G, C, and D.

[00:01:41]That's fine. They all come from the key of G. It's just when you put that flat seventh on it, it kind of screws things up a bit. So, [snorts] what's kind of happened over the years, it might have been and this is just guesswork, right?

[00:01:53]That the blues was just G, C, D, and someone went, "Let's make them seventh chords." Ooh, that sounds good and it just kind of stuck. What's happening is this G7, remember I said it's from the key of C, it's a bit like, well, that's the first chord, it's a bit like it's the five chord [music] pulling to the one chord of C, C major, right? So, this is a bit like a five to one movement, which is a one to four movement backwards. What I'm trying to say is that this chord wants to pull to this chord. So, the one chord a strong pull to the four chord. The four chord actually wants to pull I almost said to the key of F. It doesn't want to pull back to the G, but it does go back to the G, which is quite strong, but not as strong as the G going to the C. And obviously the five chord wants to pull back to the one chord and it does via the four chord. So, there's a lot of movement in the blues and this is why the blues works, right? Because we've got kind of chords within the key, we extend them a little bit to make them a little bit awkward. That creates a lot of tension. So, we've got this continual cycle of tension and release. Yes, they're kind of from the same key, but with the extensions on, they're not really from the same key. It's a little bit of both. Now, this means you can view them as being from the same key or not from the same key. Now, how does this work? Well, that means if I've got G7, C7 and D7 and I view them as coming from one key, I should be able to play one scale over this. And the one scale works, and this is weird again, is G minor pentatonic. Not a major pentatonic, a minor pentatonic. This minor pentatonic fits well across all three chords. Because the three chords are kind of from one key, this will fit across them, right? And if you look at the notes in G minor pentatonic, they fit really well with the C chord, they fit quite well with the D chord, and they kind of fit with the G chord. The problem with the G chord is it's got that major third in, but minor pentatonic has got that minor third. But what we do is >> [music] >> we tweak it a little bit and it pulls it towards the major third. So the minor pentatonic over the dominant seventh chord works really well and it's got that bluesy sound to it. So most people will treat a blues as one key and just play G minor pentatonic across it. But if we think over G7, >> [music] >> G major pentatonic, then we go over C, >> [music] >> and we go C major pentatonic and then D, >> [music] >> D major pentatonic. I'm treating it a bit more like it's three separate keys.

[00:04:45]Cuz the other thing I'm doing is I'm putting in the flat sevenths, right? I'm going G major >> [music] >> flat seven, yeah, C >> [music] >> flat seven. Now these flat sevenths cool because they're kind of unique to the chord, right? If I add the flat sevenths in, I'm very much thinking that it's like three different keys. Now I don't have to do one or the other, I could do a bit of both. I could do G major pentatonic with a flat seven over the G chord, right? And when it goes to C7, I could just do G minor pentatonic across this. I can mix and match it all over the place. So by viewing the blues as being either from one key or three separate keys, I can change how I approach harmony over the top of it and create some really cool lines, and that's where the magic happens. Catch you next time.