Guitar tuner reference tunings ♦ Guitar tunings ♦ easy to use tones 6 & 12 string, bass + guitar open tunings ♦ accurate and easy to use ♦ helps to improve pitch recognition for guitar and improve your ear by tuning to pitch. ♦ guitar tuner ♦ 11 Open tuning - Rolling Stones, Dylan, Celtic, Hendrix / Zeppelin, Nick Drake and Stanley Jordan guitar tunings .. Open D, Open G, Low C, DADGAD, BEBEBE, Eb/D# , CGDFGD, CGDFCE, GGDGBD, All Fourths & Open D6.