The Coltrane Minor Blues “Equinox”

I want to look at a third chord sequence now and it just consists of changing one of the bars of our previous chord sequence. Namely, we change bar nine from F minor 7 to A flat 7.

This is a classic chord sequence, at least known to me through the music of John Coltrane. So I’m going to refer to this as ‘Trane – ‘Trane short for John Coltrane – the ‘Trane blues. The function of the A flat 7 chord, again, I’m going to delay until we discuss the blues sequence in general. But for the moment, let’s just accept that this is the chord sequence that we are investigating. So in terms of the chords of the last four bars, we have an A flat 7 – 13th shape – G7 – 13th shape – C minor 7 – first inversion – if we use lower voicings.

The significance of this is that this is the chord sequence behind my favourite blues, which is “Equinox”, written by John Coltrane, from his classic album “Coltrane’s Sound”, which involved McCoy Tyner on piano – we will say more about McCoy a little bit later – the polyrhythmic drumming of Elvin Jones, and Steve Davis on bass. ‘Trane used different bass players throughout his classic quartet, but the pianist and the drummer remained constant.

“Coltrane’s Sound” was recorded in 1964. “Equinox” was originally played in C sharp minor. I’ve only ever played it in C minor. I’ve only ever seen it written out in C minor. So we’ll stick to C minor.

The album starts off with 14 bars of a Latin feel, and then it goes into the slow-medium swing of the rest of the track.

There is a kind of arrangement in three parts, really: the bass player has a line to play, the pianist has chords that are played in a rhythmic pattern, and then the tune goes over the top. So let’s look at the three elements. So the first thing is the bass line. It goes like this – 1, 2, 1, 2, 3, 4.

Then it repeats.

Then Tyner plays chords similar to what I’ve written out in the music to the following.

Right. We’ve met the first chord – – it’s C minor 7, first inversion. The second chord – – you could think of as a variation of the first chord, where you’re just moving and inner voicing. But, in fact, it’s going to turn out that this is a chord in its own right — a fourth-based chord – for C minor 7 which we shall look at later. It’s the analogue of the 6/9 for C major 7. This is the same thing, but the third is flattened

and then an extra note is added: the G, which is played with the third finger –

to thicken the chord. And the reason for thickening the chord is that all the chords are four-note voicings and so you get a similar texture throughout the whole piece. OK, so that’s the chords that make up the C minor 7 section. The chords which make up the F minor 7 section are the same …

and back …

and then A flat bar – the A flat 7 bar – you play the 13th voicing but, again, we add — with our 3 – the note B flat, the thickening note to keep the chord at the same thickness. Exactly the same thing with G7, the 13th shape – with the thickening note of A. And then back home.

Let’s play this with a playalong. Before I do that, this will be the underlay for the horn player. And when you play chords under a horn player who’s soloing or playing the tune, it’s known as “comping”.

So let’s make this a two-fisted comping: where we play that pattern in the left hand, but in the right hand, we add – in this case, we’re just making it an octave C with G in the middle.

We get the F bit, we do exactly the same thing, except we move the G down to F – we don’t have to, but you can do.

And the when we get to A flat, let’s move the octave and the fifth down to A flat. And similarly, when we get to G7, do the same thing.

So this is the underlay over which the chords (tune) goes. I’ll play it with a playalong. Unfortunately, there isn’t an Aebersold playalong for “Equinox”. I don’t know why, because it’s a well-known tune. So we’ll make do with the C minor blues track we used before. 1, 2, 1, 2, 3, 4.

So we get to the second chorus. Now the tune. Let’s play the tune with our playalong. I’ll play the tune using double octaves.