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Open G tuning is an alternate tuning favored by Keith Richards and requires the guitar to be tuned to D-G-D-G-B-D. To retune into open G from standard tuning, drop the sixth, fifth and first strings down a tone.
The open strings form a G chord, but, where open D tuning has its root note in the bass, here in open G, the low string is a D.
It’s still a note in the G chord (G-B-D), but it means you’ll often find chords and riffs phrased around an open fifth-string root. The tuning is common in many styles including Hawaiian ‘slack key’ and bottleneck blues.
Here are five chord shapes you need to learn in open G tuning.
1. G5
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With its G-G-G-D-D arrangement of notes, this first chord is near impossible to play in standard tuning.
2. C/G
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This chord offers a way to create boogie riffs by moving between an open-string G chord and this C/G fingering.
3. D
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It’s well worth having a fingering for the V chord (D) of the key of G up your sleeve.
4. C#maddb9
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This minor version the major shape includes a lush sounding b9th interval.
5. Aadd11
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This chord sounds great, and the dissonance between the major 3rd (C#) and 11th (D) adds color.