Singer played off The Stonemans, a family country-music band also known as The Stoneman Family, with the ultimate stonemen, the Mt. Rushmore Four. The split-venue concerts paired Joe Cocker and Van Morrison, considered by some to be the finest rock poet since Dylan.
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.