His gig at the Fillmore in 1967 convinced budding Blues-man Buddy Guy that he could give up his day job. Guy counted this appearance at the Fillmore West in 1970 with Blues-master B.B. King as one of his "best times." Singer's poster was a reference to King, the king of [Blues] clubs.
During his Fillmore era, from 1969-1971, Singer created more posters for Graham than any other artist. Singer's posters are notable for his use of collage, incorporating thousands of images clipped from magazines spanning several decades. He developed a format that included a stunning variety of lettering styles, applying them in close relation to the theme or subject of a poster.