Lydian #6 Mode on Guitar: Notes, Chords & Examples

Lydian ♯6 is a bright, futuristic, and slightly unstable mode. It has the floating “open sky” sound of regular Lydian, but with an extra twist: the raised 6th.

That ♯6 gives the mode a strange, synthetic tension. On guitar, it can sound:

Dreamy and cinematic
Progressive and angular
Fusion-like and harmonically rich
Slightly alien or “outside”
Bright, but not traditionally happy

If Lydian sounds like a major scale floating upward, Lydian ♯6 sounds like that same brightness pushed into more exotic, progressive territory.

This is not one of the everyday rock modes like Dorian, Mixolydian, or Phrygian. It is more of a color mode for players who want unusual melodic tension over major-type chords.

How does it sound?

Before anything else, let’s hear how it sounds. This can best be done by playing a chord from the mode, and playing the notes of the mode arpeggiated on top of it. This is the best and quickest way to determine the feel of a mode.

This can be quickly done using SLModes, a software dedicated to the music modes, and the following sound was generated by it:

Formula

The interval formula for C Lydian ♯6 is:

1 2 3 #4 5 ♯6 7

Compared to the C major scale:

C major: C D E F G A B

C Lydian ♯6: C D E F# G A# B

So the changed notes are:

#4 = F#
♯6 = A#

The #4 gives the mode its Lydian sound.

The ♯6 is what makes it more unusual and synthetic.

Notes in C

The notes of C Lydian ♯6 are:

C D E F# G A# B

Important spelling note: The raised 6th is written as A#, not Bb.

On guitar, A# and Bb are the same fret in standard tuning, but the theory meaning is different. In this mode, A# functions as a raised 6th, not as a flat 7th.

That matters because the mode also contains B, the major 7th. The A# and B sit right next to each other, creating one of the most distinctive tensions in the scale.

A Chord That Defines the Mode

A compact chord that brings the raised-fourth pitch into C Lydian ♯6 is:

Cmaj7b5

Notes: C E Gb B

The chord’s Gb is enharmonically equivalent to F#, the mode’s raised fourth.

This chord combines the major third and major seventh with the pitch responsible for the Lydian tension. Its diminished fifth replaces the perfect fifth; it is not an added tone above a complete major-seventh chord.

For a smoother foundation, use:

Cmaj7

Notes: C E G B

The complete mode is C D E F# G A# B. Neither of these chords contains A#, the raised sixth.

Feature A# in the melody, particularly through A#–B, to distinguish this mode from ordinary Lydian. Keep its scale spelling as A#: the mode also contains B, its major seventh.

Chord Progression (Example)

Cmaj7b5 – D7#5 – Cmaj7

Chord	Notes
Cmaj7b5	C E Gb B
D7#5	D F# A# C
Cmaj7	C E G B

Every pitch belongs to C Lydian ♯6, with Gb used as the chord spelling of F#.

D7#5 is especially useful because it contains both characteristic altered tones: F# and A#. Returning to Cmaj7 lets F# rise to G and A# rise to B.

Keep the C-rooted chords prominent so the progression remains centered on C rather than sounding like a passage toward another key.

Mood: Bright, floating, and unsettled.

Guitar Fretboard Shape

Here’s the mode mapped across the full fretboard, generated with my software SLModes.

The diagram shows every occurrence of the mode across the neck:

🟢 Green dots = the root note, your anchor points
🟠 Orange dots = the rest of the scale tones

Why Guitarists Love This Mode

C Lydian ♯6 has a rare emotional balance.

It is major, but not simple.

It is bright, but not innocent.

It feels open and elevated because of the #4, but the ♯6 adds tension that makes the sound more complex and unpredictable.

This makes it useful when regular major or Lydian feels too familiar.

Genres Where It Works Well

C Lydian ♯6 can work in:

Progressive rock
Progressive metal
Jazz fusion
Modern instrumental guitar music
Cinematic scoring
Ambient guitar music
Experimental songwriting
Game soundtrack-style composition

It is especially useful when you want a major tonal center with a futuristic edge.

Tips for Practicing

To practice a mode effectively, you only need two things:

An instrument to play the mode (your guitar is ready to go!)
A backing track that provides a harmonic context

The fretboard diagram above already show you where the notes are. The remaining piece is choosing an appropriate backing track to improvise over.

Practice with a drone

The simplest option is a single C drone.

You can create one using:

A looper pedal
A synth drone
A sustained bass note in your DAW
An open C tuning
Or any other source of a continuous C note

Because the accompaniment consists of only a single note, you are responsible for highlighting the intervals that define the mode. The more intentionally you emphasize its characteristic tones, the more clearly the modal sound will emerge.

Create modal vamps with SLModes

While a drone is an excellent way to hear a mode in isolation, a modal vamp often provides a more musical and rewarding practice experience.

A well-designed backing track naturally emphasizes the mode’s characteristic intervals, allowing you to focus on phrasing, melody, and expression instead of constantly trying to establish the modal sound yourself. As a result, improvising in the character of the mode often feels more intuitive.

There are many ways to build modal backing tracks, but SLModes can generate them for you in just a few clicks. For example:

Arpeggiated backing tracks — a repeating pattern that outlines every note of the mode.
Chord vamps — progressions built from chords that best reinforce the mode’s unique character.

This video shows you an example: