Reharmonization is the process of composing new chords for an already composed (and harmonized) melodic line. Hearing that melody in a fresh harmonic context can bring new meanings to the theme, provide variety for an arrangement, underscore lyrics, and even totally change the mood of the piece. Reharmonization is also a fun and creative way to learn more about harmony and the relationship of a melody to its accompanying chords…great things to know for a composer, arranger, improviser…and for every musician. You could think of it as a new way to tell an old story…much like the new movie versions of old film classics, books, plays, fables, myths, etc. A great example would be the musical, “West Side Story”…which is based on Shakespear’s “Romeo and Juliet.” While the “story” (or melody) may be someone else’s, reharmonization allows the musician to express his own voice in many creative ways.
If you are new to the art of reharmonization, there are a couple of steps to try first. Begin with just harmonizing a simple tune in the key of C major…a children’s song, old folk tune, easy Christmas carol, etc.,…something whose melody you are familiar with. This means you must first find where the melody begins in relation to its key center. Does it start on the first note of a major scale, the fifth note…the third? Nothing fancy here…just try to play the song’s melody and original chords on the piano (knowing that if you start on a white key, that doesn’t neccesarily mean you will be playing in the key of C). Even if the tune has only a couple of chords, getting your ear attuned to what chord goes where and the frequency in which those chords change is a solid fundamental skill you can build on. During this process you may discover that your inner ear is already beginning to imagine more chords than the original version.
I’ve included a simple system of chords here that you can use for this purpose, with the Roman numerals showing each chord’s function in the key of C (you can click on this image for a larger version). The upper tier of chord symbols apply to the triads directly above them. The 7ths in parenthesis signify chords that could add the 7th on top of those written triads’ root, 3rd and 5th. Also, the lower tier of chord symbols suggest a few more variations that might also be of use, depending on the complexity of the song…but really, the simple tunes I was thinking of to start with won’t be so harmonically involved. Most likely an easy tune in C major will only use (in a rough order of frequency) the I, V, IV and VI chords, with possibly a minor IV chord. The lower tier minor chord symbols will lower the 3rd of the written chord above by one half step (for example C-E-G becomes C-Eb-G), while the Dominant 7th chords will raise the 3rd by one half step (D-F-A becomes D-F#-A-C).
It would also be a good idea to study the melodic and harmonic structures of great songs. Bach’s sonatas for solo instruments are full of arpeggios and scales that suggest the harmonic underpinnings, and the Real Book series of fake books have tons of great tunes from what many call the “Great American Songbook”…Tin Pan Alley songs, and themes from Broadway musicals and movies, that have become a part of the jazz repertoire. The Real Books also provide wonderful examples that illustrate the evolution of the harmonic language in jazz. Years ago I devoured my first Real Book…playing every tune at the piano, trying to unlock the secrets of the music that had so completely captured my interest, and learned more during that period of study than with all of the theory classes I had taken in college. Using Roman numerals to describe the function of the chords (for example IIm7-V7-I, I-VIm7-V7, I13-bVII13, etc.) helps to recognize the strong harmonic patterns that frequently appear in many songs, no matter what the key, and makes it easier to catalog your favorite chord progressions for future uses. Understanding a chord’s function is also a huge step towards deciding the applied scales for the chord. Observing the relationship of the melody note(s) to the accompanying chord will also help you discover more of the melodic possibilities over each chord.
Although the topic of what constitutes strong harmonic motion is beyond the scope of this post, if you take the time to follow the steps listed above you will be well on the road to understanding the subject (plus you will have more than enough knowledge to begin reharmonizing your first tune!). As with most endeavors, the better you lay the foundation, the more you will be able to build on top of it.
Here are some guidelines I try to keep in mind when reharmonizing a tune:
- Start with a song that you know very well and feel an affinity towards. If there are lyrics to the song, learn them and be sensitive to them when choosing any new harmony.
- Play the melody alone and listen within the imagination of your own inner ear for ideas that may spring from that space.
- There should be a consistent “Hip Factor”…my term for the melody’s relationship to the chord below it. In the standard “Nature Boy” (shown below) the first three notes are the 5th, 3rd and root of a Dm chord…very basic, and that relationship continues throughout the piece, with the main melody notes usually the root, 3rd, 5th or 7th of the supporting chord of the moment. My final reharmonization (seen at the very end of this post) is another story, with the first three notes now being the 13th, 11th and 9th of the opening chord…a much higher Hip Factor. There is a certain personality each note from every chord’s applied scale has (see the previous post”A Casting Call for All Notes“), and while every person has their own take on what that “flavor” might be, working with this perspective in mind will help make your reharmonization more consistent with itself and more unique. Try playing the melody A-F-D over a D minor chord, and then over a C minor chord and hear the different mood that is created.
- The new harmonic structure should have a strong form that relates to both the melody and the structure of the piece. Just like the bridge of a tune can present new motivic material, the harmonies should also reflect contrast when the song enters a new section…different harmonic rhythms (the rate at which the chords change), pedal points, mode changes (like major to minor), etc.
- The bass line (in this case, the simple course taken by the chord progression’s roots) is the second most important melody. Although it usually moves much more slowly than the melody, it’s shape and activity has a tremendous impact on the overall arc of the song, so always be aware of the bass line in relationship to both the melody and the song’s structure.
These two reharmonized versions of Nature Boy also show the original chords (the lower tier of chord symbols) that were found in a fake book (I’ve seen different “original” chords in other fake books). I must admit that my knowledge of the lyrics comes from my memory of hearing vocalists’ versions of the tune…not as complete as a good lyric sheet. Here’s a quick analysis:
- The middle tier of chords (Reharmonization #1) shows more harmonic activity, first with the addition of the Bm7b5…a substitute chord for the Dm (sharing the common tones D-F-A), that gets the bass line moving down the interval of a 3rd (which is considered strong.
- Measures 2 and 4 both have strong IIm7-V7 progressions. Measure 2 is approached from the preceding Bm7b5 with the same strong bass motion (an interval of a 4th up/5th down) that leads all the way back to Dm in measure 3.
- Measure 4 is approached from the preceding Bm7b5 with the same down a 3rd interval seen earlier, and its dominant C7 chord leads in strong fashion down 1/2 step to measure 5’s Bm7 (this is called a “tritone substitution” in the jazz lingo, which mimics the 4ths up/5ths down root motion mentioned earlier).
- Measures 5 through 7 are a chain of IIm-V7’s (V13’s) leading to the Fmaj7 (the relative major of the beginning Dm chord) in measure 8, although the Fdim chord provides a little surprise first and delays that final cadence by two beats. While measures 5 through 7 might be somewhat clever and akin to more common jazz reharmonizations (which often seem rather homogenous to me), I find them unsuited to the spirit of the piece.
- The top tier of chords (Reharmonization #2) begins with four measures of triads over a pedal point of D in the bass, with the melody note present in every triad as they first occur (the first chord voicing from bottom to top would be D-C-F-A). This technique imparts its own unique sound to the reharmonization, with the dissonance of the final Eb/D begging for some sort of resolution (and creating a different kind of strength to the harmonic motion than found in Reharmonization #1).
- The next four measures achieve a strong, ascending bass line with an assortment of cadences in measures 5 (a Deceptive Cadence…V7-VI, where the A/G can be also be thought of as a G13#11 chord without its 7th…G-B-D-A-C#-E), measure 6 (another Deceptive Cadence one whole step higher), and measure 7 (a VIIdim-Im). The A#dim chord is a substitute for an F#7b9/A# (again with the common tones associated with chords that are a 3rd apart). If you think of this as an F# chord, then it would be a strong V7-Imin cadence.
Honoring all of these gidelines is like playing three dimensional chess with Star Trek’s Mr. Spock…you must be aware of what is happening on more than one level at the same time during this game. The new chord progression must be strong, while at the same time it should relate to its melody in consistent ways (unless you are consciously going for contrast). If there are lyrics, then add one more dimension that needs to be considered. One of the wonderful by products of this process is the new progression of chords that you may never have arrived at without the guidance of the working melody. And here’s one more idea to try out…one of my friends likes to reharmonize a tune, and then write a new melody over his new chord progression, which gives him an original tune that is all his own.
Below is my final reharmonization of Nature Boy (clicking on it will give you a larger, printable version). You can hear a very rough arrangement based on these chords on the “More Audio” page of my website. At the time the recording was made, I was only experimenting with the new string, piano and acoustic bass samples I had just bought, rather than going for a final, CD worthy recording, but you can still clearly hear the reharmonization. After the eight bar intro, the melody is played a little more freely, and there are additional measures added at the end of every eight bar phrase. Even if you don’t have a great background in theory, see if you can see evidence of some of the guidelines discussed earlier:
- changes in overall harmonic structure (types of chords, pedal points, etc.) that relate to major motivic changes in the melody
- consistent “hip factor”…how the melody relates harmonically to it’s underlying chord
- bass line…the piece’s underlying shape. With slash chords (like Db maj7/C) consider both the root of the chord (Db maj7) and the bass note below it (C)