Space plays and stops
- Notes and intervals
- F#M3A#m3C#m3E4A
- Extends
- F# Dominant 7
F# Dominant #9, written F#7#9, is built from F#, A#, C#, E and A: the root, major 3rd, 5th, minor 7th and sharp 9th.
Its 3rd and 7th, A# and E, 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. C7, a tritone away, has the same two notes the other way up, so it can stand in for F#7#9 as its tritone substitute.