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
Bouzouki better suited to the kind of virtuoso playing he was famous for. Today, the tetrachordo is the most common bouzouki used in Greek music, though a few traditionalists still prefer the trichordo, particularly for the older "rebetika" style of playing. In addition to developing the modern tetrachordo bouzouki, Manolis Hiotis was a pioneer the use of amplification for the instrument, which he may have been using as early as 1945. However, the earliest documented use of amplification for the bouzouki comes from a 1952 photograph, showing Vasilis Tsitsanis and Yiannis Papaioannou playing bouzoukis, each with an electric guitar-style pick-up attached