The Lydian scale is a major scale with a sharp 4th, and that one raised note makes it sound bright, dreamy and weightless. It's the fourth mode of the major scale and the go-to sound for film scores, fusion and floating rock ballads.
Formula
| 1 | 2 | 3 | #4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|
| G | A | B | C# | D | E | F# |
Steps: W W W H W W H. The reference key is G Lydian, and it's what the diagrams below use. It has the same notes as D major, starting from G. Compared with G major (G A B C D E F#), only one note changes: C rises to C#.
Sound and character
In the major scale the 4th is the note that clashes with the major 3rd and wants to fall onto it. Lydian removes that clash: the #4 is a tritone above the root and sits comfortably over a major chord. The result sounds open and unfinished, like a question hanging in the air.
Where it's used
Film and game music, dreamy pop, jazz, fusion and instrumental rock. It fits maj7, maj7#11, add9 and plain major chords, especially the IV chord of a major key (G in D major), since that chord's natural scale is Lydian. The chords built from it are G, Am, Bm, C#dim, D, Em and F#m; as 7ths, Gmaj7, A7, Bm7, C#m7b5, Dmaj7, Em7 and F#m7. The move that makes it sound Lydian is G to A over a G bass (I to II).
How to move it
The root is the amber dot. Slide the whole pattern so the amber dots land on the new key's root: move everything up 2 frets for A Lydian, or down 2 frets for F Lydian, with the root at the 1st fret.
Related scales: Lydian is the major scale with a #4. Lower its 7th and you get Lydian dominant, a mode of melodic minor.
The second exercise returns to the open G between every note, so you hear each degree, and above all the C#, against the root.