Complex sentence: One of these instruments was the preferred guitar of American composer John Fahey, who recorded extensively on the instrument from 1969-1978, when it was severly damaged in a domestic quarrel between Fahey and his girlfriend at the time.
Split into simpler sentences: One of these instruments was the preferred guitar of American composer John Fahey, who recorded extensively on the instrument from 1969-1978. It was severely damaged in a domestic quarrel between Fahey and his girlfriend at the time.