Open G (GDGB) Tuning
Tune your mandolin to Open G (GDGB) — G3, D4, G4, B4
About Open G (GDGB) Tuning
Open G tuning (G3-D4-G4-B4) produces a G major chord when all courses are strummed open. The A course is lowered from A4 to G4, and the E course is lowered from E5 to B4. This transforms the mandolin into a natural chord instrument where simple barre shapes produce major chords at every fret.
Open G has deep roots in blues and folk mandolin traditions. Early blues mandolinists like Yank Rachell used open tunings to create slide-like effects and droning accompaniments. In old-time string band music, Open G mandolin pairs naturally with banjo in standard Open G tuning, creating a wall of ringing G major sound.
The tuning makes strumming and rhythmic playing easier — open strings ring as a full chord, and power-chord shapes require minimal fretting. The trade-off is that scale patterns change completely from standard tuning, so melodic playing requires relearning the fretboard.
String Notes
Recommended Strings
Standard mandolin strings handle Open G well since both changed courses are tuned lower. The reduced tension on the top two courses gives a slightly mellower sound. If strings feel too loose, consider medium gauge. The lower two courses (G and D) remain at standard pitch.
How to Tune to Open G (GDGB)
- 1.Start from standard GDAE tuning. Two courses need to change.
- 2.Lower the A course (2nd from top) from A4 down to G4 (392 Hz). It should now match the lowest course (G3) one octave higher.
- 3.Lower the E course (highest) from E5 down to B4 (493.88 Hz).
- 4.The G course and D course stay at standard pitch.
- 5.Strum all courses open — you should hear a full G major chord: G-D-G-B.
Common Chords in Open G (GDGB)
G Major (open)
All courses open. A full, ringing G major chord with no fretting required.
C Major (barre at 5th)
Barre all courses at the 5th fret for C major. Slide to any fret for other major chords.
D Major (barre at 7th)
Barre at the 7th fret for D major. Combined with the open G, this covers the I-IV-V in G.
Em
Simple shapes over the open G strings create natural minor voicings for added emotional range.