Space plays and stops
- Notes and intervals
- D#M3F##m3A#m3C#
D# Dominant 7, written D#7, is built from D#, F##, A# and C#: the root, major 3rd, 5th and minor 7th.
Its 3rd and 7th, F## and C#, are its guide tones: they say what kind of chord it is, so voicings are built around them and the root is often left to the bass. A7, a tritone away, has the same two notes the other way up, so it can stand in for D#7 as its tritone substitute.
In the progressions here, D#7 is the VI7 of the Major I-VI-ii-V Progression in F#, the III7 of the Cycle of Dominants in B and the VII7 of the Coltrane Changes in E.