F#aug9(#4) Augmented
The F#aug9(#4) chord is built from the notes F# – A# – C## – G# – B#.
Piano sound loads on first tap.
Chord tones, one by one
F#Root
Root
The fundamental note the chord is built on — F#.
A#Third
Major third
Four semitones — makes the chord major (brighter, happier).
C##Fifth
Augmented fifth (♯5)
Eight semitones — a sharp fifth. Restless and dreamy, typical of augmented chords.
G#Extension
Ninth (9)
A 9th — colorful extension a whole step above the octave.
B#Extension
Sharp eleventh (♯11)
A ♯11 — the bright, floating Lydian color.
🎼 Related scales
Lydian augmentedmelodic minor a minor 3rd below
🎹 Modal analysis
This chord implies the Lydian augmented scale; its characteristic note is the dreamy, suspended ♯5. It is a mode of the melodic minor a minor 3rd below.
🎸 Genres
Film & TV scoring · Modal jazz · Impressionism

