Open D tuning

Open D, from the 6th string to the 1st: D A D F♯ A D. Frequencies are for A4 = 440 Hz.

Open D tuning is D A D F♯ A D. Strum the open strings and you hear a D major chord: the root D on the 6th, 4th and 1st strings, the fifth A on the 5th and 2nd, and the major third F♯ on the 3rd. Because the open strings already form a chord, a finger, a bar or a slide laid across all six strings at any fret gives another major chord.

It is one of the oldest guitar tunings in American music. Old blues and parlor guitar books call it Vestapol tuning, a name taken from a 19th-century guitar piece, The Siege of Sebastopol.

Open D is open E tuning (E B E G♯ B E) moved a whole step lower. The chord shapes are identical, but open E gets there by tightening three strings above standard, while open D only loosens strings. Many slide players choose open D for that reason: less tension on the neck and no risk of snapping a string tuned up past its usual pitch.

Four strings move and two stay. The 6th, 2nd and 1st strings each drop a whole step, the 3rd string drops only a half step (G to F♯), and the 5th and 4th strings keep their standard A and D. Those two unchanged strings are your anchors: tune the others to them.

By ear, the 6th string should sound one octave below the open 4th string, the 1st string one octave above it, and the 2nd string one octave above the open 5th string. The 3rd string at its 3rd fret should match the open 2nd string, A. Once everything is close, strum the open strings: a string that is off makes the chord wobble, and the wobble slows as you get closer.

The 3rd string is the one people get wrong, because it moves only one fret. If you lower it a whole step out of habit, like the others, it lands on F and the open chord sounds sad instead of bright. The F♯ button and the tuner catch that at once.

A slide laid across all six strings plays a full major chord wherever it rests. Open is D, the 5th fret is G and the 7th fret is A, the three chords of a blues or folk song in D, and the 12th fret is D again an octave higher. Much of open D slide playing is moving between those spots and sliding into them from a fret below.

Rest the slide right above the fret wire, not between the frets where your fingers normally press, or the chord sounds flat. Keep it light: pressing the strings down onto the frets makes it rattle. Resting a finger of the fretting hand on the strings behind the slide damps the unwanted overtones.

The 3rd string carries the third of every barre chord in open D, so minor chords come from one change: fret the 3rd string one fret lower than the bar. With the bar at the 5th fret (G), the 3rd string at the 4th fret makes G minor; with the bar at the 7th fret (A), the 3rd string at the 6th fret makes A minor.

For fingerpicking, the three D strings give a steady drone. A thumb alternating between the 6th and 4th strings keeps the bass going while the fingers play a melody on the top strings, which is how many open D blues and folk arrangements are built.

Open D sits one string away from DADGAD: raise the 3rd string a half step, from F♯ to G, and the open strings turn from a D major chord into the suspended DADGAD sound. Switching between the two takes seconds.