My first rock concert was The Doors, Fillmore East, March 22. 1968, 8PM show, as a 14 year old HS freshman with HS buddies. What an introduction to rock concerts.
Classical music was well before that, I believe at 10 years old seeing Carmen at the old Metropolitan Opera House. I also remember seeing Young Peoples Concerts,, New York Philharmonic, Bernstein conducting at Philharmonic Hall at an early age. My parents got me hooked on classical.
Jazz was before that. Probably at 8 years old. I can visualize to this day Guy Lombardo pulling up to the stage at the Jones Beach Theater in his stunning wood power boat and leading his orchestra.