The 1st printing poster pre-dates the concert and is characterized by a purple/blue background, light gray border, and darker brown grid which match the postcard. It measures 13 15/16" x 19 7/16".
The 2nd printing displays a red/purple background, darker gray border and gold colored grid. It has a very small dot in the gray top margin about 1/8" above the left side of the "O" in "Oct.", which is not on the 1st printing. It is also shorter and wider, measuring 14" x 18 15/16". It was printed after the concert.
Trained as a commercial artist, Bob Fried came to San Francisco from New York to study at the Art Institute and work as a free-lance designer. In 1966, he began to look at the rock posters that were appearing throughout the Bay Area. Encouraged by Victor Moscoso, whom he met at the Art Institute, he began to create his own posters. He wanted to keep them simple to convey feelings of dimensional space, similar to an acid trip. Fried attempted to convey the feeling of the plasticity of time that was his experience on LSD.