Aadd9 Major
The Aadd9 chord is built from the notes A – C# – E – B.
Piano sound loads on first tap.
Chord tones, one by one
ARoot
Root
The fundamental note the chord is built on — A.
C#Third
Major third
Four semitones — makes the chord major (brighter, happier).
EFifth
Perfect fifth
Seven semitones — the most stable interval, reinforces the root.
BExtension
Ninth (9)
A 9th — colorful extension a whole step above the octave.
🎼 Related scales
🎹 Modal analysis
This chord implies the Ionian (major) scale; its characteristic note is the perfect 4th, what sets it apart from Lydian.
🎸 Genres
Pop · Classical · Gospel
🎤 Artists who made it famous
Steely Dan · The Police