and it was no quaint brass band that was going to play in fifteen minutes or half an hour , either -- spread across the band-shell ( which looked almost as big as the hollywood bowl to mary 's eyes ) were the implements and accessories of what had to be the world 's biggest -- and loudest , judging from the amps -- rock-and-roll band , an apocalyptic bebop combination that would , at full throttle , probably be loud enough to shatter window-glass five miles away .