Jerry Garcia’s 75th birthday will be marked with an all-star concert at Red Rocks on August 4 featuring Bob Weir and his Campfire Band as well as a special band assembled in Garcia’s name. Joining that band will be longtime Garcia collaborators Melvin Seals, Jackie LaBranch and Gloria Jones as well as Oteil Burbridge, Kamasi Washington, Tom Hamilton, Duane Trucks and more artists to be…