Strange Man Dressed In Black/ A Real Gent/ True or False

There is a similarity between these titles and the previous set. Carl remembers playing with a Jazz Rock band in his University days and their main venue was in a downstairs basement. Everything was pitch dark and suddenly this sound engineer would arrive from nowhere dressed in black which could scare you at times! He only muttered a few words and that was it. The band were all fascinated by this individual and could never figure out where he came from or what he was about.