Lesson 22 - Tritone Substitutions

The tritone substitution is one of the most common chord substitutions found in jazz and was the precursor to more complex substitution patterns like Coltrane changes. Tritone substitutions are sometimes used in improvisation—often to create tension during a solo. Though examples of the tritone substitution, known in the classical world as an augmented sixth chord, can be found extensively in classical music since the Renaissance period, they were not heard until much later in jazz by musicians such as Dizzy Gillespie and Charlie Parker in the 1940s, as well as Duke Ellington, Art Tatum, Coleman Hawkins, Roy Eldridge and Benny Goodman.

The tritone substitution can be performed by exchanging a dominant seven chord for another dominant seven chord which is a tritone away from it. For example, in the key of C major one can use D♭7 instead of G7. (D♭ is a tritone away from G).