What is Open C tuning?

Open C tuning is C-G-C-G-C-E (low to high). Strumming all strings produces a C major chord. The low C string sits two whole steps below standard E, giving exceptional bass depth.

What scales work in Open C?

C major and C major pentatonic are the most natural choices. C Lydian adds a dreamy, cinematic quality. For heavier styles, C minor and C Phrygian deliver dark intensity.

Do I need heavier strings for Open C?

Yes, the low C string needs a heavier gauge to maintain proper tension — at least a .056 or .058 for the 6th string. A set of 12-56 or similar is recommended. Without heavier strings, the low C will sound muddy and floppy.

F Prometheus Guitar Scale

Guitar scale in Open C tuning — fretboard diagram

Tuning

Frets

F Prometheus in Open C — Notes and Intervals

The F Prometheus scale was developed by the composer Alexander Scriabin as his Mystic Scale. On Guitar, the notes are F, G, A, B, D, Eb. It is a synthetic hexatonic system designed to reflect his theosophical beliefs and reveal spiritual truths that exist beyond human conceptualization. Commonly used in Contemporary Classical, Impressionist, Experimental, Film Scores. Notable players include Alexander Scriabin, George Crumb. Use over the Mystic Chord (C-F#-Bb-E-A-D) and its inversions. Also works over 7#11 chords as a sophisticated alternative to Lydian Dominant.

Notes: F, G, A, B, D, Eb

Intervals: 1P, 2M, 3M, 4A, 6M, 7m

Degrees: 1 2 3 #4 5 b6

Formula: W-W-W-WH-H-W

Number of notes: 6

Tuning: Open C (C-G-C-G-C-E)

About Open C Tuning

Open C tuning (C-G-C-G-C-E) produces a C major chord when strummed open, with an enormous bass depth from the low C string (two whole steps below standard E). The tuning spans a vast tonal range that gives compositions an almost orchestral scope, making it a favorite for both delicate fingerstyle and crushing heavy music.

John Butler's 'Ocean' — one of the most famous modern fingerstyle compositions — is performed in Open C, showcasing the tuning's incredible dynamic range from thundering bass to shimmering harmonics. Devin Townsend uses Open C extensively across his catalog for its massive, wall-of-sound potential. Jimmy Page used it on Led Zeppelin's 'Friends' from Led Zeppelin III. Soundgarden also explored Open C. The three C strings and two G strings create powerful octave resonances that make even simple chord shapes sound huge.

Fingerstyle AcousticProgressive Rock/MetalPost-RockFolkExperimental

Notable artists: John Butler, Devin Townsend, Jimmy Page (Led Zeppelin), Soundgarden, William Ackerman

Best for: Cinematic fingerstyle compositions, progressive metal walls of sound, post-rock textures, and any music that needs enormous tonal range from deep bass to bright treble

Musical Character

MysticalSpiritualComplexTranscendent

Scriabin's 'Mystic Chord' turned into a scale (1, 2, 3, #4, 6, b7). Designed to reflect theosophical beliefs about spiritual transcendence — neither major nor minor, but something beyond both.

Explore This Scale in Other Tunings

← All Guitar scales in Open C tuning