• Open C (‘Wide Major’) tuning •



Open C (unlike Open D, G, A, and E) doesn’t quite correspond to any of our familiar EADGBE chord shapes. It’s closest to the classic ‘xx0232‘ Dmaj shape in terms of interval pattern (actually it’s like ‘making a Dmaj shape in Drop D’, then all minus 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




John Butler’s Ocean instrumental (a track that helped persuade my teenage self to go acoustic) sets it superbly on a capoed 12-string…well, actually an 11-string: Butler removes the 3str’s high double. He also uses it on plenty of other songs – e.g. Zebra, Betterman, What You Want.


Countless more through time: Friends (Jimmy Page), Question (Moody Blues), Caledonia (Dougie MacLean), Old Pine (Ben Howard, c5), King of Spain (Kristin Matsson, c8), Busted Bicycle (Leo Kottke, -3), Souls Like The Wheels (Avett Brothers, c4), and many by Ewan Dobson compositions including Time 2. And electrics don’t handle the looseness so well without a restring – but Devin Townsend makes it sounds great!


  • Ocean – John Butler (2008):


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 less C


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


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rāga: ‘that which colours the mind’

George Howlett is a London-based musician, writer, and teacher. I play guitar, tabla, and santoor, loosely focusing on jazz, rhythm, and other global improvised traditions. Above all I seek to enthuse fellow sonic searchers, interconnecting fresh vibrations with the human voices, cultures, and passions behind them. Site above, follow below, & hit me up for…


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Dedicated to Nigel Tufnel – a true tuning connoisseur

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