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.

Few songs sum up that Friday night feeling more enthusiastically than 'Good Rocking Tonight,' the oft-covered jump blues classic written (and originally recorded) in 1947 by Roy Brown. A local New Orleans hit in its initial incarnation, 'Rocking' went on to new life in the hands of rock 'n' roll forerunner Wynonnie Harris, who turned it into a chart-topping R&B hit and set the stage for its eventual ascension to the ranks of full-fledged rock standards.

By the time Montrose covered the song (apostrophizing it as 'Good Rockin' Tonight') for their self-titled debut album in 1973, it had already been re-recorded by everyone from Elvis Presley to the Doors, but they still managed to put their own spin on it -- no mean feat, considering how well-known it had become, not to mention how little room for stretching out the arrangement offered (at a whopping three minutes, Montrose's take on the track is nearly a full minute longer than Presley's version).

Unfortunately for Montrose, the album failed to generate much heat on the charts, in spite of the inclusion of such future FM standards as 'Bad Motor Scooter' and 'Rock Candy.' Like vocalist Sammy Hagar's eventual solo career, the band's success was a slow-building phenomenon fueled largely by ceaseless touring -- and by the time the mainstream audience caught up, the band was already a thing of the past, having endured a number of lineup changes before dissolving in the late '70s.

Bandleader and guitarist Ronnie Montrose, who cut his teeth on stints in Van Morrison's band (that's his riff you hear in the opening moments of 'Wild Night') and the Edgar Winter Group, kept moving throughout the '80s and '90s, steering the post-Montrose band Gamma through a series of records while maintaining a solo career (and even resuscitating the Montrose banner for a 1987 LP, 'Mean,' that featured future Foreigner vocalist Johnny Edwards). While his later years never produced anything quite as radio-friendly as those first few Montrose records, he remained a well-respected figure in discerning rock circles.

Sadly, we lost the 64-year-old Montrose on March 3, 2012. ut while his absence is still deeply felt, his music lives on, and his best records have barely aged -- like 'Good Rockin' Tonight,' which is every inch the failsafe party jam in 2013 that it was 40 years ago. So scroll on up to the top of this post, hit play on that video embed, turn up the volume on your speakers, and let the weekend start...now.

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