Irish bouzouki Johnny Moynihan (apparently in an attempt to replicate the open, droning sound of Appalachian "clawhammer" banjo) first on the mandolin and then transferred to a Greek bouzouki. It was later picked up by Andy Irvine and Dónal Lunny, and quickly became the next thing to a standard tuning for the 4 course instrument. Other tunings used, although by a minority of players, are "octave mandolin" tuning G2 D3 A3 E4, and "Open D" tuning A2 D3 A3 D4. "Open G" G2 D3 G3 D4, is used by some players and has proven useful for "bottleneck" slide playing. The GDAD tuning
Irish bouzouki families are related and the bouzouki is a part of that. At any rate, since the genesis of the Irish bouzouki in the late 1960s, luthiers have incorporated so many aspects of mandolin construction, particularly when building archtop Irish bouzoukis, that for most it is a moot point. For many builders and players, the terms "bouzouki", "cittern", and "octave mandolin" are more or less synonymous. The name cittern is often applied to instruments of five courses (ten strings), especially those having a scale length between 20 and 22 inches (500mm and 550mm). They are also occasionally called "10 string bouzoukis"