The Four-course Bouzouki (tetrachordo)
This type of bouzouki has 8 metal strings which are arranged in 4 pairs, known as courses, typically tuned Cc Ff aa dd (i.e., one whole step below the four high strings of a guitar). In the two higher-pitched (treble) courses, the two strings of the pair are tuned to the same note. In the two lower-pitched (bass) courses, the pair consists of a thick wound string and a thin string tuned an octave apart. These 'octave strings' add to the fullness of the sound and are used in chords and bass drones (continuous low notes that are played throughout the music). The guitar-like tuning was introduced by composer and soloist Manolis Chiotis, who found it better suited to the kind of virtuoso playing he was famous for. Traditionalists shun the 4-course as they feel it alters the character of the instrument. Many musicians such as the aforementioned Chiotis and Giorgos Zampetas began using specially designed pickups to achieve a slightly thicker humbucker-like sound in the mid-1960s. These pickups are widely used by several Greek artists today and came in active and (usually) passive versions.
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