Chord Substitution vs Chord Superimposition: How to Play 2 Chords at The Same Time
One of the most difficult concepts that I see students struggling with as they learn how to play jazz guitar, is being able to see one chord on a leadsheet, or hear it being played by their bandmates, while playing a different chord over top of that change. Though it is tough to really get this concept down, it is an essential tool for any jazz guitarist to have in their tool belt, and so it is worth checking out and putting the time in to bring this concept into your comping and soloing.
There are two main ways to approach playing one chord over a different chord change, superimposed chords and substituted chords (often called chord subs or simply subs). Both of these concepts offer unique ways to play one chord over another, with superimposition focusing on altering the color of the underlying chord, and substitution creating tension over the underlying chord. Both are worth exploring in the practice room as you continue your development as a jazz guitarist.
In this short primer on chord substitution and chord superimposition, we will define each technique, show how it can be used over a static chord and a four-bar phrase, and finally bring it to a jazz blues progression in F to give a real-life example of how to use these important concepts in your playing.
These two concepts are very important and can be difficult for many players to get down when they first explore these ideas. So, take your time. Start with one idea, one chord, one approach and work it in the practice room until you are fully comfortable with using it in an number of situations. Then, move on to the next idea in the article.
There is no hurry to rush through these concepts, and it is much better to get one small idea down fully in your playing then to rush all of these approaches haphazardly into your comping and soloing.
What Does it Mean to Superimpose a Chord?
When you are superimposing one chord over another during your comping or improvising, this means that you are using a different chord from what is on the leadsheet, but one that is directly related to that given chord.
For example, in the notation below you can see that there are two bars of F7. In the first bar you could play it as written, the F7, while in the second bar you could superimpose an Am7b5 over the F7 chord in the leadsheet.
Notice how the Am7b5 uses intervals from the F9 chord voicing, 3-5-b7-9, so it has a different root note and chord quality than F7, but it is directly related to the F9 extension of that chord.
This approach (playing the 3 to 9 superimposed chord over the given change) is a common approach to chord superimposition. Other common superimpositions are playing the iim7 chord over the V7 chord and vice-versa (playing Cm7 over F7 or F7 or Cm7 for example), as well as playing the vim7 or iiim7 chord over the Imaj7 chord (such as Em7 or Am7 over Cmaj7).
When superimposing chords you are altering the color of that change, such as turning F7 into F9, but you are not necessarily creating tension that needs to be resolved. For that approach, you will use chord substitution.
What Does it Mean to Substitute a Chord?
Substituting a chord means that the chart says to play one chord, such as the F7 in the example below, and you are playing a chord that is not built from or directly related to that particular chord, such as the E7 in the example below.
Whereas superimposed chords come from the chord extensions or chord scale that is related to the chord in the chart, chord subs are often used to relate to a previous or subsequent chord in the progression.
For example, below you see two bars of F7, with an E7 being used as a chord sub in the second bar. Here, the E7 could be used to create tension by playing an “outside” chord over F7, or it could be used to lead the changes from F7 to either A7 or Eb7 if that chord was the next change in the progression.
Basically, chord subs are changes that you play over top of the given chord, but that don’t have to be directly related to the chord on the page at that time. They are used to create tension that is resolved in a subsequent measure by returning to the given chord, or by resolving to the next chord in the tune.
Blues in F With Superimposed Chords
In this example, you can see the original chords in the top line and the superimposed chords below on the bottom staff.
For the first and third bars in the progression I superimposed an Am7b5 over F7, creating the F sound we saw earlier. Then, I used a Dm7b5 over Bb7 in bar two, again creating a 3 to 9 sound but this time over a Bb9 chord. Finally, in bar four, I played a Cm7, the iim7 chord, over F7, the V7 chord in the key of Bb.
To work on these changes, you might want to try each one separately first before applying them to the full, four-bar phrase.
Try putting on an F7 vamp in Band in a Box and improvising over that chord using only the Am7b5 arpeggio, and then only the Cm7 arpeggio. After that, try mixing them together, move between the Am7b5 and Cm7 arpeggios, then sneak in F7 to move between all three chords, the original change and two superimpositions.
After you’ve worked on each chord separately, try applying this technique to other parts of a blues in F, and to other tunes that you are working on in the practice room. Start with the 3 to 9 and iim7 over V7 sounds, then branch out from there and see what you can come up with on your own.
Blues in F with Substituted Chords
Now that you have checked out a few superimposed chords over the first four-bars of an F blues, let’s look at using chord subs over the same four bars.
In this example you can see the original changes in the top line and the substituted chords in the bottom line.
These chords are being used to create tension starting in bar 2, which will then be released in bar 5 when the B7 chord in bar 4 moves down by a half-step to Bb7, the chord that is found in the next bar.
The chord subs used in this example are commonly played by many jazz greats, such as John Coltrane and Joey DeFrancesco. They start in bar one on the tonic chord, F7 and then move up in whole-steps in each bar, F7-G7-A7-B7, creating more tension along the way, before finally resolving to the Bb7 chord in bar 5.
This is the most important aspect of using chord subs in your soloing or comping, these tensions need to be resolved at some point or else the subs end up sounding like mistakes and not purposeful chord choices.
Because of this, it is good to work out subs over common chord progression, such as the first four bars of a blues, so that you can practice resolving these “outside” chords in the practice room before taking them onto the bandstand.
Once you have worked on the example below, playing the subbed chords against a play-along track to hear how they sound, try coming up with your own subs for the first four bars of the blues. You don’t have to use subs in every bar, you just want to create momentary tension that is then released in a subsequent measure.
Here are some other common subs that you can use based on this idea over the first four bars of an F blues to give you a starting point in your practicing.
Try these different changes out inn your comping and soloing to see which ones you like and which ones sound out of place in your playing. When you find a group of subs you like, either here or over any tune you are working on, stop and isolate them.
Practice them intently so that they become a part of your playing and begin to come out in your lines in an organic fashion. This will take time, but if you focus on one sub or group of subs at a time, you can really make big strides in this area during your practice routine.
Blues in F Solo
To finish off this introductory article on substitution vs. superimposition, I have written out a one-chorus solo over an F blues using both of these techniques in every bar on the tune. This is just an example to show you the extent that you could use these techniques in your soloing, but you don’t have to use them as much as this.
Often times a well-placed, single sub or superimposed chord is much more effective than a chorus filled with them. So, as you explore these ideas further in your practicing and performance, look for ways to slowly and deliberately bring these ideas into your playing without overdoing it.
Start with one chord sub or superimposed chord per chorus and build up from there, or maybe your ears think that that is the perfect amount of these sounds in one go around on a tune.
The choice is up to you on where and how you use these chords, and the more you practice them, the better you will understand and get your ears around these concepts, the easier it will be to make them sound natural in your playing.
Do you have a favorite way of applying chord subs or superimposed chords to your playing? If so, please share it in the comments section below.
About the Author
Matt Warnock is the owner of www.mattwarnockguitar.com , a free website that provides hundreds of lessons and resources designed to help guitarists of all experience levels meet their practice and performance goals. Matt currently lives in the UK where he is a Senior Lecturer at the Leeds College of Music and an examiner for the London College of Music (Registry of Guitar Tutors).