 Barrett wrote most of Pink Floyd 's early material . He was also an innovative guitarist , using extended techniques and exploring the musical and sonic possibilities of dissonance , distortion , feedback , the echo machine , tapes and other effects ; his experimentation was partly inspired by free improvisation guitarist Keith Rowe of the group AMM , active at the time in London . One of Barrett 's trademarks was playing his guitar through an old echo box while sliding a Zippo lighter up and down the fret @-@ board to create the mysterious , otherworldly sounds that became associated with the group . Barrett was known to have used Binson delay units to achieve his trademark echo sounds . Daevid Allen , founder member of Soft Machine and Gong , has cited Barrett 's use of slide guitar with echo as a key inspiration for his own " glissando guitar " style . 
