• Open C (‘Wide Major’) tuning •



Open C (unlike Open D, G, A, and Emaj) doesn’t quite correspond to any of our familiar EADGBE chord shapes – although the interval sequence is closest to the classic ‘x-x-0-2-3-2‘ Dmaj (more precisely: it’s like a ‘Dmaj shape in Drop D, then dropping everything 2 semitones’).


For me, this isn’t one to overtheorise: its simplicity makes it easy to get stuck straight into, with handy symmetries and variable string tensions. Ideal for rolling legato movements, vertical octave melodies, and vigorous rhythmic explorations. Enjoy the huge, loose low end!

Pattern: 7>5>7>5>4
Harmony: Cmaj | 1-5-1-5-1-3


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John Butler’s Ocean instrumental – a piece that helped persuade my electrified teenage self to buy a steel-string acoustic – sets it on a 4fr-capoed 12-string (…well, actually an 11-string: Butler removes the 3str’s high double – somewhat like an ‘inverse Mi-Composé concept). He also uses it elsewhere – e.g. Zebra, Betterman, What You Want.


Countless more through time: Friends (Jimmy Page), Question (Moody Blues), Caledonia (Dougie MacLean), Old Pine (Ben Howard, cp.5), King of Spain (Tallest Man on Earth, cp.8), Busted Bicycle (Leo Kottke, -3), Souls Like The Wheels (Avett Brothers, cp.4), and many Ewan Dobson pieces including Time 2. And, while electrics don’t handle the looseness so good without a restring, Devin Townsend makes it work!


  • Ocean – John Butler (2008):

“I discovered open tunings [aged 20], and realized I could just play guitar and not strum as well, [to] get a bit more instrumental…I stopped singing for about a year. Then I copied Jeff Lang and Tony McManus…they inspired me to put my songwriting back into my instrumental playing, and I’ve never looked back. I think the mixture of both of them is the most powerful thing…” (John Butler)

Insights to share? Comment via YouTube, or get in touch!


6str 5str 4str 3str 2str 1str
Note C G C G C E
Alteration -4 -2 -2 0 +1 0
Tension (%) -37 -21 -21 0 +12 0
Freq. (Hz) 65 98 131 196 262 330
Pattern (>) 7 5 7 5 4
Semitones 0 7 12 19 24 28
Intervals 1 5 1 5 1 3
  • See my Tunings Megatable for further such nerdery: more numbers, intervallic relations, comparative methods, etc. And to any genuine vibratory scientists reading: please critique my DIY analysis!


—Associated tunings: proximities of shape, concept, context, etc…

  • Open Cm (this with 1str -1): with the min. 3rd on top
  • Atta’s C (this with 4str +4): another Cmaj arrangement
  • Mauna Loa C (this with 2str -3): Cmaj with one C fewer


—Further learnings: sources, readings, lessons, other onward links…

  • Butler’s setups: for more, see a Cmaj video demo from the man himself, as well as a selection of resources from Guitar Gear and Mixdown (“…tuned to his preferred tuning of Open C…Butler’s Maton CW-80 is actually modified to be an 11-string guitar, with Butler removing the ‘ridiculous’ high G string due to its sharp sound and tendency to break…replacing the tuning peg with an ornate scroll-carving upon the headstock…”)
  • Butler’s tunings: check out his other appearances in my World of Tuning, and witness more great versions of Ocean (live at Federation Square and in the studio in 2012) – as well as interviews with Butler in MusicRadar, Premier Guitar (“His whole life changed when he was given his grandfather’s ’30s Dobro…”), and Ultimate Guitar (“I didn’t start writing lead breaks until I was 21. I was just strumming chords…So a lot of times [now], it’s pretty much a 15-year-old’s approach to guitar – but…it’s not necessarily about how good I am, but what I have to say, and how I have to say it. Some of the best guitarists are doing very simple things – you just have to take your head out of that whole thing, and go into your heart…”)

Header image: John Butler performs Ocean (2012)

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George Howlett is a London-based musician, writer, and teacher (guitars, sitar, tabla, & santoor). Above all I seek to enthuse fellow sonic searchers, interconnecting fresh vibrations with the voices, cultures, and passions behind them. See Home & Writings, and hit me up for Online Lessons!

“An intrepid guitar researcher…”

(Guitar World interview)

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