Open D Minor Tuning for Guitar

Open D Minor runs D2, A2, D3, F3, A3, D4, in playing order. The lowest-pitched string is D2 (73.42 Hz) and the highest is D4 (293.66 Hz), measured against A4 = 440 Hz. Those are the exact target frequencies the tuner on this page listens for.

4 of the 6 strings move: E2 down 2 semitone(s) to D2; G3 down 2 semitone(s) to F3; B3 down 2 semitone(s) to A3; E4 down 2 semitone(s) to D4. Work through them in order, then go back and re-check the first string — retuning shifts the neck tension slightly, so the earlier strings drift as you go.

Open D with the third string dropped one further semitone, turning the open chord from major to minor. A single string separates the two, so switching mid-set is realistic — useful when a set needs one dark piece among brighter open-D material.

D2 is 73.42 Hz at concert pitch (A4 = 440 Hz). That's the fundamental — the string also produces harmonics above it, which is why a tuner reading the wrong octave usually means it locked onto a harmonic rather than the fundamental. This is the lowest string in this guitar tuning.

One semitone separates this from Open D: the third string drops from F# to F, converting the open chord's major third into a minor third. Everything else is identical, which makes it uniquely practical among alternate tunings — a single peg turn switches the entire instrument between major and minor tonality mid-set. Slide players use exactly this to move a piece from bright to bleak without changing hand position. Because only one string differs, fingerings learned in Open D remain valid anywhere they avoid the third string, and need only a one-fret adjustment where they don't.