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.

A Diminished Seventh Guitar Arpeggio

Guitar arpeggio in Open C tuning — fretboard diagram

Tuning

Frets

A Diminished Seventh in Open C — Notes and Intervals

Notes: A, C, Eb, Gb

Intervals: 1P, 3m, 5d, 7d

Formula: WH-WH-WH

Number of notes: 4

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

Also known as: dim7, °7, o7

The A Diminished Seventh arpeggio contains 4 notes (A, C, Eb, Gb). Use the interactive fretboard above to explore this arpeggio on 6-string guitar — Open C with different tunings and fret ranges.

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

Explore This Arpeggio in Other Tunings

← All Guitar arpeggios in Open C tuning