In dictionaries:
Open C tuning
an open tuning for guitar.
Open G tuning
Among alternative tunings for the guitar, an open G tuning is an open tuning that features the G-major chord; its open notes are selected from the notes of a G-major chord, such as the G-major triad.
Open D tuning
an open tuning for the acoustic or electric guitar.
Open E tuning
a tuning for guitar: low to high, E-B-E-G-B-E.
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