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 for that than Friday evening, when we pick up our paycheck, punch out of work and enjoy a couple days of much-needed rest and relaxation.

Among the many complaints frequently leveled at the modern music business, one of the most common is that labels no longer have the patience or resources to really take the time to nurture a band's career. Where artists once had the luxury of releasing a few less-than-successful records before losing their deal, these days it's far more common to see an act put out one or two albums before being forced to move on. There were still plenty of flashes in the pan in the old days, of course, but it's true that a number of bands took their time to catch on before scoring that first big hit. REO Speedwagon might have taken longer than any of them.

In fact, the band didn't even break the Top 40 until it released its seventh studio LP (and eighth overall), 1978's memorably titled (and distinctively covered) 'You Can Tune a Piano, but You Can't Tuna Fish.' Coming after a string of personnel changes and little-heard records, 'Tuna Fish' delivered REO Speedwagon's first real measure of nationwide success, vindicating nearly a decade of label support from Epic Records and hinting that the band's years of nonstop touring were about to finally pay off in a big way.

While the group wouldn't achieve mainstream success until 1981, when their 'Hi Infidelity' album topped the charts on its way to selling 10 million copies and spinning off four Top 40 singles, 'Tuna Fish' demonstrated that all the key ingredients were already there. Chief among them was the perfectly balanced musical tension between the group's two main songwriters, singer Kevin Cronin and guitarist Gary Richrath -- a tension clearly borne out in early REO standouts like the big single from 'Tuna Fish,' 'Roll With the Changes.'

A solo folk performer before he was brought into the band, Cronin tended to bring a softer side to REO Speedwagon's music, while Richrath was far more prone to crank up his amps and just rock out. It took some finagling for the two to achieve some balance -- Cronin left the band for a spell in the '70s, while Richrath would eventually be forced out in the late '80s -- but when they managed to bridge the gap, the duo combined for some of the most perfectly radio-ready rock of the era, including 'Roll With the Changes.'

Although Cronin's thin, keening voice isn't ideally suited for harder-edged rock numbers, he knows how to write a catchy melody, and on 'Changes,' his singing is solidly propped up by the sort of cleanly aggressive arrangement REO would soon become known for: propulsive drums, banging rock piano, a swirling organ solo, singalong background vocals and Richrath's squealing electric leads. Like a lot of the era's other rock bands, REO Speedwagon went on to Top 40 success with a string of prom-friendly ballads, but it's tracks like 'Changes' that made them a favorite with longtime fans -- and that continue to give their live set its energy. Although it was far from their biggest hit, it's one of their best, and it remains one of the band's signature songs.

It's also a mighty fine song for a Friday, with enough rock muscle to help you blow off a little end-of-the-work-week steam while leaving plenty of room for the sort of sunny pop hooks that capture payday levels of optimism. You know what to do, weekenders: Scroll on up to that video at the top of the post, hit play, turn up the volume and let those changes roll.

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