Reharmonization is one of those things that beginning jazz piano players often find pretty confusing. In some ways reharmonization can be confusing, but just like anything else in jazz, you can use a few formulas to get started and immediately enhance tunes that you're working on.
Don't be turned off by the word forumulas. Fundamentally, the rules of jazz piano are the like the rules of physics. If you drop an apple, it's going nowhere but down. Great artists know how to mix colors using formulas, great craftsmen use formulas to create bird houses, and great jazz pianists use formulas to reharmonize.
As time goes on you don't think about the formulas and you figure out ways to break the rules and expand what you do, but you gotta start somewhere and now is the best time to do it. Why is that? Because everything happens now.
We're going to take a look at:
- Leading Chords
- 2-5-1 Substitution
- Tri-Tone Substitution
- Cirlce of 5ths
(note- sorry about the poor graphics on most of the examples, I'll update them when I have a chance.)
Leading Chords
A leading chord is a 7th chord that is 1/2 step above the chord you want to go to.
A leading chord is just what it sounds like. Take a look at the following blues snippit:
Normally, this first part of F blues would go like: || F7 | Bb7 | F7 | F7 || but we are adding some extra chords. The B7 is leading to the Bb7, the Gb7 is leading to the F7.
Classical theory teaches you about leading tones, notes that lead into the next melody note but are not necessarily all that important in the big melodic picture. They are more of an embellishment to the melody. If we reharmonize with leading chords, we are not changing the music in such a way that it ruins it, we are simply adding a bit of tension for a moment until we get back to the chord everyone expected us to play in the first place.
Jazz is about tension and release, as is every performing art.
Here's an example based on the first few measures of Autumn Leaves. Each of the target chords is preceded by a leading chord (Gb to F7, E to Eb, etc).
2-5-1 Substitution
2-5-1 substitution reharmonization is useful when you have a 2-5-1 chord and you want to add color to it. Here's a basic 2-5-1 in the key of C:
Now, take a look at a simple but effective 2-5-1 substitution:
The example starts on the same chord, and ends on the same chord, but what are all those extra chords in there? This is a basic 3-6-2-5-1 turn around. What that means is we're basically putting in an extra 2-5 into the 2-5-1 progression. Since the normal 2-5-1 starts on a Dm chord, we want to lead into the Dm somehow and the easiest way to do that is by putting the 5 of the Dm in front of it, and that's the A7. In this case it sounds better to lead into the A7 with it's own 2 chord, the Em. This is a piece of the Circle of 5ths (see below.)
You can use it nearly anywhere you see a 2-5-1. Experiement with this by trying it in your own lead sheets where you see a 2-5-1 chord.
The next example is also a 3-6-2-5-1. The only difference is the chord voicings. These are voicings that I might use in a performance. If you like any of those voicings after you play them, be sure to practice them in all keys. It will only take you a few minutes and it's well worth it.
Practice all new cool voicings you discover in 12 keys right when you discover them. You'll be happy you did.
This next example is from the end of the A section in the tune, "On Green Dolphin Street" in the key of Eb. This shows you another voicing that I might use to move into a minor chord. The bridge starts on the 2 minor (in this case an Fm) so to get there we'll add the 2-5 of Fm in the preceding bar. This will lead right into the Fm and sound like what they do on recordings. Note that the C7 chord is altered to anticipate the following Fm7 chord by flatting the 13 (Ab) and flatting the 9 (Db). I flatted those notes because they become leading tones for notes in the Fm chord.
One of the biggest tricks to jazz is to know what is coming next well before you have to play it. Always be aiming for the next important harmony or melody.
Now, we will take that same progression and alter it a bit further by adding the 3 and 6 chords to it.
in this example we used a 3-6-2-5 to get to the Fm. If you had enough space, you could use a 4-7-3-6-2-5 to get there if you want, but you must use good judgement so it doesn't sound too formulatic (that is, bad.) We are brushing on the circle of 5ths here, as some of you may have guessed. We'll be getting to that in just a little while.
Tri-Tone subtitution
Tri-Tone substition is one of the oldest tricks in the book and one of the coolest tricks in the book. Simply put, you substitute the written chord with the 7th chord that is a tri-tone (a 4th raised a half step) away.
This is often the last reharmonization trick a jazz piano player will learn. The reason for this is not that tri-tone substition is the last trick there is, it's just that it's so easy that a lot of players decide not to go any deeper. Don't make this mistake. Use the tri-tone substituion for all it's worth, but continue figuring out new ways to harmonize. We'll touch on some more ways in another lesson.
Let's continue messing around with the last part of the A section in Green Dolphin Street. In this next example, I take out the 6 chord, but leave the 3 chord. Keep in mind here that I am relating these chords to the key of Fm which is how the B section starts.
Note: Try the above reharmonization and substitute a G for the bass note in the Db7 chord. Sounds pretty cool, eh? That's what tri-tone substitution can do for you- you often don't even have to change the right hand at all, just the bass note. The reason for this is that when you sub using the tri-tone method, the 3rd and the 7th are interchangeable. That is, the third becomes the 7th and the 7th becomes the third.
The 3 chord of Fm is Ab, and that has been left in as an Ab7. The 2 chord is a Gm, but we substituted the tri-tone for that and put in a Db7 instead. The 5 chord in Fm is the C7, but we also did a tri-tone substitution on that chord and inserted a Gb7. This is all in preparation for the Fm at the beggining of the B section.
Remember that accidentals (sharps and flats) are carried throughout the entire measure. When the next measure line occurs, then they are reset. If this is new information for you, it would be beneficial for you to take a basic music theory class at your local community college.
Here's what I'm talking about with the 3rd and 7th being interchangeable:
The C7 chord has the E as the 3rd and the Bb as the 7th, but the Gb7 chord has the E as the 7th and the Bb as the third.
Circle of 5ths
The Circle of 5ths is nothing more than a term used to describe the 2-5 relationship between chords. D to G, C to F, F to Bb. This is very important for you to get a handle on. Many chord changes that you will find are related to this circle of 5ths in some way, and much of the reharmonization we do is related to it. The Jazz Theory book by Mark Levine talks about it in detail and is a pretty good book.
Using the circle of fifths is a great way to practice chord change patterns. Cm-F7, Bbm-Eb7, Abm-Db7, etc... Then, alter the chords in all the ways imaginable. Anything that sounds good to you should be done in all 12 keys!

Want to see the circle of 5ths in action? Take a look at the opening bars of All The Things You Are, a standard we should all know. The first few bars ARE a piece of the circle of fifths, then there is a 2-5-1 into the key of C.
Have fun!
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