Led Zep. My friends and I went to see Jimmy Page and Robert Plant and went home amazed at John Paul Jones's 3 neck guitar play during their acoustic set and John Bonham's drumming. Page was incredible, but by the time you'd seen them a few times the guitar and bow thing got old. The solos in those days were great for going to the bathroom. They were 4 amazingly talented musicians when they were on their game. I don't remember another hard rock band in the 70s that did an acoustic set like Zep.

If you can still hear, you weren't there.