Now before you get your panties in a bunch, the picture on the left is just for fun. There is no “Rhythm Changes for Dummies” book, though I’m sure someone has thought about writing it.

If you’ve ever wondered where the “Rhythm” in “Rhythm and Blues” comes from, now you know. “Rhythm Changes” is a chord progression found in many jazz songs, modeled after the song “I Got Rhythm,” which was written by George and Ira Gershwin. It has become one of the most important song structures in jazz, and if you have any desire to be a jazz performer you absolutely need to have the song nailed.

Today I want to give you a general overview of the changes, some variations, and a few ideas on how to improvise over them.

(This really would be a cool book, though…)

The Chord Changes

Let’s start with the typical chord progression for a Rhythm Changes song. Unless the bandleader is on crack, Rhythm Changes will always be played in Bb.

‘A’ Section

BbMaj7 / Gm7 / | Cm7 / F7 / |  Dm7 / G7 / |  Cm7 / F7 / |

BbMaj7 / Bb7 / |  Eb7 / Edim / |  Dm7 / G7 / |  Cm7 / F7 / |

Repeat this ‘A’ section

‘B’ Section

D7  /  /  /  |  D7 /  /  / | G7 /  /  /  | G7 /  /  / |  C7 /  /  /  |  C7 /  /  /  | F7 /  /  / |  F7 /  /  /  |

‘A’ Section

BbMaj7 / Gm7 / | Cm7 / F7 / |  Dm7 / G7 / |  Cm7  F7  BbMaj7 / |

It’s a pretty simple progression, actually, with an AABA song form.

Basic Chord Substitutions

Quite often you will see chord substitutions taking place to spice up the harmony a bit. The first and most obvious one happens right in the first measure, where players will often turn the Gm7 into a G7 to lead into the Cm7 more smoothly:

BbMaj7 / G7 / | Cm7 / F7 / |  Dm7 / G7 / |  Cm7 / F7 / |

Sometimes you will also see the Gm7 turned into a Bdim, which gives you chromatic root movement from Bb to C:

BbMaj7 / Bdim / | Cm7 / F7 / |  Dm7 / G7 / |  Cm7 / F7 / |

Both ways sound cool, and you’ll definitely have to keep on your toes to hear what the rest of the band is playing to know how to address the harmony.

You can certainly play with the other chords as well, but since this is a “Dummies” post I’m going to stick with the most common and basic elements.

Improvisation

So, how do we improvise over this song? First, keep in mind that this song is generally played “up”, meaning fast. The more experienced the players, the faster they generally like to play the song to give them more of a challenge. My suggestion to you, as a newbie, would be to take the changes slowly! (I will make a playalong track with the basic changes and put it on the Downloads page this week.)

If you feel so inclined, you can simply play Bb Major over the entire ‘A’ section. If you do this then there will be a few wrong notes. (The Bb over the G7, for example, will give a #9 sound, which technically isn’t wrong but you’ll probably alert everyone to the fact that you are a beginner if you are careless). But it’s an okay place to start.

If you really want to start digging in from the get-go, I suggest you start with simple arpeggios. Don’t try to be fancy, just get the sound in your head.

Here’s another one:

Next, start adding some altered tones. For example, every time you hit one of the dominant 7 chords, play the b9.

I hope you’re starting to get the idea. You can also use the tritone substitution principle; when playing over a dominant 7 chord, play your line as if you were playing over its tritone substitution. So, for example, over the G7 you would play a C#7 line. Here are a few ideas over the ‘B’ section:

Comping

Because Rhythm Changes songs are usually played very quickly, you don’t want to play full chords when you comp. It will sound muddy, you will probably have a coronary trying to get to each chord, and it won’t give the improviser any sonic room to play in. Here are some suggestions for how to comp over the changes:

1. Small voicings. Only play the 3rd and 7th of each chord (dyads).
2. Guide tones. Play only one note that represents the harmony, in a scalar fashion.
3. Don’t play all the time. Especially in the bridge, there is no need to play the entire time. Sit out for a few chords, or maybe even a bar or two. Give the song some breathing room.
4. Basic chords. Keep the chords simple; don’t add many extensions, and leave out any alterations (b9, #5, etc). The alterations will be covered by the improviser should he choose to play them. If you add the alterations then you and the person you are comping behind are going to run into each other and it will sound like crap.
5. Simple rhythms. Keep your rhythms simple and clean. Don’t add a lot of syncopation. Remember, the song is going by very quickly. You don’t want to present problems for the rest of the band, and certainly not for the people listening. KISS (Keep it Simple, Stupid!)

Rhythm Changes on its face is not an impossible hurdle. But, the possible changes and alterations can make it somewhat daunting (I still struggle with it). These changes are to be digested slowly. Don’t go nuts trying to fit in every alteration, substitution, and chromatic idea all at once. Take your time and work through the ideas one at a time. Play diatonically first, then progress through simple alterations (like the b9 I described above). In time you will get it.

Of course, transcribing the masters is a great way to learn. Here is a list of some heads that are Rhythm Changes. I suggest you find as many recordings as you can and start listening.

Ah-Leu-Cha
Anthropology
Cotton Tail
Crazeology
The Eternal Triangle
Flying Home
Good Bait
Lester Leaps In
Moose the Mooche
Move
Oleo
Rhythm-a-ning
Seven Come Eleven
The Theme