A tritone (a.k.a. augmented fourth, diminished fifth,) is a flat 5 above a root. It consist of an interval of 3 whole steps -i.e. 6 semitones (frets) above a root note. As the diatonic scale consist in 6 whole steps, at tritone is also called a half octave.


If you ad a tritone to the Pentatonic Minor Scale, you get the Blues Scale. The tritone is one of the “blues note” (b5 above the root) in the blues scale.

A tritone is also found in the Diminished Scale, the Whole-tone Scale.

See also