The meaning of the Marshall amp

"If it's too loud, you're too old." And, by now, probably half deaf.

I have been to plenty of rock concerts. At some of them, you couldn't really hear the music, which does seem to lessen the quality of the experience. It wasn't that the music was too soft to hear: it was too loud. The recently deceased Jim Marshall, creator of the Marshall amp, can be directly tracked as the source of volume in stadium rock. Like most people, I knew that there was such a thing as a Marshall amp, so I marginally understood why his passing was noted. An article by William Weir explains it:

Marshall...had the fortune of having a 20-year-old Pete Townshend for a customer. Townshend told Marshall he wanted to hear himself over The Who's audience and rhythm section. Thus was born the first 100-watt amp. Add to that two cabinets, each bearing four speakers—together, the components came to be known as the Marshall stack—and Marshall secured himself a permanent spot on any history-of-loudness timeline... Townshend's wish to hear himself play over his bandmates and audience was certainly a reasonable one. But his discussing it with Marshall—who could actually do something about it—might be the moment arena rock was born, and the start of a widening divide between audience and performer.

In other words, it was the beginning of the battle of the bands versus the listeners' eardrums: How the Marshall Amp Changed Rock—and the Meaning of 'Loud'.