My first 3 concerts were all at Winterland Ballroom in SF in 1975...
1. KISS - Jan 31,1975, I was 13... Hotter Than Hell tour...
Its on Youtube.... https://www.youtube.com/watch?v=4rsMBKHsaOA
2.) Peter Frampton June 13, 1975 ... exactly 1 week before turned 14.
They recorded this show and it Frampton Comes Alive ... released Jan 6, 1976.
3.) Black Sabbath Aug, 31, 1975 ... Sabotage tour
Opening acts were Mahogany Rush and Grey Ghost