"Wall of sound"

If you think this read is about Phil Spector's "wall of sound", stop reading now. There's nothing for you here. This blog post is about Marshall stacks a.k.a. Marshall walls. Marshall stacks driven by 100 watt heads was the aesthetic ideal during the 1970s. Another aesthetic ideal was a deafening sound that left an indelible imprint. The louder, the better. The size of the Marshall wall became an indicator of status, even when rendered obsolete by improved PA systems. It's a long time since you needed a 6*3 stack to be heard. However, the trade mark and imagery was so strong that later bands put up fake walls of Marshall stacks just for show. Fake, empty or dummy stacks isn't an admirable standard. We can call them "vanity stacks". Back to the "play it loud" ideal. Led Zeppelin were known for playing loud, circa 100 db(A). High volume may cause hearing damage. A volume of 115 dB(A) risks permanent damage after only 30 seconds. The Guinness Book of World Records recognised Deep Purple as the "globe's loudest band" in 1972 for a concert at the London Rainbow Theatre, during which the sound reached 117 dB. The Who later reached painful 126 dB. Playing loud comes at a price. Their guitarist and songwriter Pete Townshend suffered from hearing loss and tinnitus as a result of years of exposure to loud music. The Guinness Book of World Records discontinued the category for fear of encouraging hearing damage. Loudness can be measured by observation or by reputation. To complicate things further, it's hard to measure. Decibel measurement is dependent on distance from the source of the sound; if this is not given, the sound level reported is of limited use. Temporary ringing in the ears is a normal reaction to the kind of extreme noise that causes hearing loss. Back in the days, ringing in the ears was a sign of that you had been to a concert.