Open D

Open D tuning is an open tuning for the acoustic or electric guitar. The open string notes in this tuning are (from lowest to highest): D A D F♯ A D. It uses the three notes that form the triad of a D major chord: D, the root note; A, the perfect fifth; and F♯, the major third.

To tune a guitar from standard tuning to Open D tuning: Lower the 1st (high-E), 2nd (B), and 6th (low-E) down a full step. Lower the 3rd string (G) down half a step to F♯.

In this tuning, when the guitar is strummed without fretting any of the strings, a D major chord is sounded. This means that any major chord can be easily created using one finger, fretting all the strings at once (also known as barring); for example, fretting all the strings at the second fret will produce an E major, at the third fret an F major, and so on up the neck.

Open D tuning is very popular with slide guitar (or 'bottleneck') players, as it allows them to play complete chords using the slide. This tuning is also used in regular (non-slide) guitar playing. The full and vibrant sound it produces - particularly on an acoustic guitar - also makes it ideal for fingerstyle playing.

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