Classic rock is about heavy hooks, power chords, and tight harmonies, but it’s also about letting loose and enjoying the good times — and there’s no better time than Friday evening, when we pick up our paycheck, punch out of work, and enjoy a couple days of much-needed rest and relaxation.

Today, we're paying tribute to a song that, for a distressing number of people, is best remembered as the theme song to a television show -- but long before it was used to punctuate David Caruso's opening-sequence quips in 'CSI: Miami,' the Who's 'Won't Get Fooled Again' served as a powerfully cathartic anthem for the disaffected.

A big part of the song's appeal is its distinctive sound, which required no small amount of technical jiggering during the 1971 sessions that produced the track -- led by the synth-filtered organ riff that kicks in following the opening electric guitar power chord and envelops the listener for most of the first 30 seconds. But it isn't just synth tinkering that helps set the song apart; bassist John Entwistle played a heavily modified instrument, nicknamed 'Frankenstein' because he'd cobbled it together from the pieces of five smashed basses, while Pete Townshend's setup found him running a '59 Gretsch hollow-body guitar through a Fender Bandmaster amp with a pedal steel volume pedal (all of which was an incredibly useful gift from Joe Walsh of the Eagles).

All of which is fascinating for rock gearheads, but to the casual listener, the song's most crucial ingredient might be the spine-tingling howl that Roger Daltrey unleashes at the 7:45 mark -- a rock scream so potent that it boasts an increasing number of YouTube tributes as well as its own Facebook page. It's the perfect wordless manifestation of the song's lyrics, which -- while they've been heavily misinterpreted for decades -- offered a jaded rebuttal to the 'power to the people' revolutionary fervor that was in vogue at the time (and which tends to resurface once a g-g-g-generation).

Townshend wrote at length about the song's true meaning for a 2006 entry in his online diary, telling readers it was inspired by what he called "the power of music and congregation." As he put it, "Despite its looseness, and its decadence, rock has lasted a lifetime, and still seems to prevail as the impudent portal for the naive complaints of the hopeful young."

But just because those complaints are naive doesn't mean they aren't true, or even necessary. "It is not precisely a song that decries revolution," Townshend pointed out. "It suggests that we will indeed fight in the streets -- but that revolution, like all action, can have results we cannot predict. Don't expect to see what you expect to see."

No matter how hard you hope for change, in other words, you still have to contend with the hard truth of reality. Meet the new boss, same as the old boss. But if it isn't as idealistic as its title implies, neither is it as strictly cynical as that line might suggest. As Townshend put it in that diary entry, "Expect nothing and you might gain everything."

Recalling an interaction with director Spike Lee, who used 'Won't Get Fooled Again' during a key moment in his film 'Summer of Sam,' Townshend mused that Lee "told my manager that '...he deeply understood Who music.' What he understood was what he himself -- like so many others -- had made it. He saw an outrage and frustration, even a judgment or empty indictment in the song that wasn't there. What is there is a prayer."

So whether you feel like screaming or praying this Friday -- or maybe even both -- 'Won't Get Fooled Again' offers the perfect soundtrack. Why wait until five o'clock? Hit 'play' on the clip below, crank up the volume, and let the weekend start now.

Watch the Who Perform 'Won't Get Fooled Again'

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