In 1968 Mickey Hart of the Grateful Dead was studying at the Ali Akbar College of Music with Tabla Master Shankar Ghosh. Mickey would work on compositions with Shankar which included Rhythmic Cycles of 4, 6, 16, 5 and 7, and take these teaching to Bill Kreutzmann. Mickey and Bill were instructing Shankar on traps in exchange for Tabla lessons, and would combine their knowledge in compositions of East and West.
In September of 1968 the Grateful Dead played a concert at the Berkeley Community Theater. Before the concert the drummers had planned a surprise for the audience. During part of "Alligator", the G.D. amps rolled apart and two risers rolled on stage between Mickey and Bill. On them were Shankar Ghosh and Vince Delgado, a fine dumbec player and a student of Shankar's. The four men sat and fixed compositions together, taking a rhythmic journey through many "Tals" or time cycles. Ali Akbar Khan composed the closing compositions for them and when they were finished, the applause was deafening.
(excerpt from the United Artists Diga Rhythm Band bio, May 1976)