Superimposing common arpeggios can add a new and exciting sound to your solos, helping you to utilize patterns and shapes you already know.
When we "superimpose," we take one sound and layer it on top of another. In other words, when playing over a particular chord, you "think" a different chord in your improvisation. All it takes is modifying your approach over the chord you're playing over.
One of my favorite superimposed sounds is made by playing major 7th arpeggios over a minor 7th chord. But you need to play the major 7th sound starting on the minor 3rd of that minor 7th chord.
Let's look at how to use this idea over an Am7 chord. The notes that make up the Am7 are: A (root), C (b3), E (5th), G (b7). If we play a C major 7th arpeggio over Am7, we are superimposing the sound of one chord over another! And a C major 7th arpeggio over Am7 works nicely.
The notes that make up a Cmaj7 arpeggio are C (root),E (3),G (5),B (7). But these notes, measured against the Am7 chord we are playing over, become: C (b3), E (5), G (b7), B (9). And it's the B note, which is the 9th of Am7, that adds the color to the line. Another way to think of this is as a Am9th arpeggio.
Check out the lesson video below to hear the sound of superimposed arpeggios. The example in the lesson utilizes a challenging Cmaj7 sweep arpeggio over an Am7 chord. The tabs for this lesson are available at carlroa.com.