Hi Folk, and welcome back for more lashing of red hot theory. This week I’m going to delve into the arcane mysteries of the dread “Tritone Substitution”, a diabolical techique where an innocent dominant 7th chord is substituted for more diabolically satanic alternative…ahem!
Sorry…little musical joke – if you want the scoop, here’s an excerpt from wikipedia.
It seems first to have been designated as a “dangerous” interval when Guido of Arezzo developed his system of hexachords and with the introduction of B flat as a diatonic note, at much the same time acquiring its nickname of “Diabolus in Musica” (“the devil in music”).
Seriously though – tritone substitution is a seriously useful harmonic technique for spicing up your accompaniment/arranging/song writing options. Check out the video here:
Accompanying materials are available here: