For such a pivotal album in the storied career of Judas Priest, Sin After Sin sure seems to slip the minds of modern-day fans and critics. But the British heavy metal gods' third album built an important bridge between the first, largely unheralded portion of their career, and the second, where they came to enjoy so much global acclaim.

After all, when Sin After Sin arrived on April 8, 1977, Judas Priest remained a promising but unproven proposition, still lurking in the commercial shadow of Black Sabbath and Led Zeppelin, despite the significant creative growth spurt undertaken between 1974's uneven Rocka Rolla and 1976's astonishingly accomplished Sad Wings of Destiny.

Priest were most definitely on the rise, and the music industry seemed to sense as much when major label CBS Records decided to sign the band away from independent Gull Records.

Now the stage was set for vocalist Rob Halford, guitarists Glenn Tipton and K.K. Downing, and bassist Ian Hill to prove their worth. They just needed a drummer to fill the void left by Alan Moore, eventually settling on session ace Simon Phillips. For a producer, the group turned to Deep Purple bassist Roger Glover, and together they entered London's Ramport Studios, armed with a new selection of brazen metal anthems and a few surprises.

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First out of the gate, "Sinner" was a monument to the progressive metallic songwriting achieved on Sad Wings, written by Tipton and Halford, graced with a stunningly atmospheric guitar solo from Downing, and culminating in a metallic crescendo and Halford shriek. Next up was a groundbreaking cover of Joan Baez's "Diamonds and Rust," already attempted for the previous LP, but now completed for the majors and some much needed radio airplay.

From this point forward, fierce head-banging ruled on "Starbreaker," "Call for the Priest" and "Dissident Aggressor" (later covered by Slayer), where Phillips' jazz-fusion experience gave heavy metal some of its earliest double-bass drum examples in the pre-thrash era. Yet these forceful tracks rubbed shoulders with more experimental material, ranging from ballads like the dreamy "Last Rose of Summer" and the dramatic "Here Come the Tears," to the brazenly homoerotic "Raw Deal," where Halford pretty much came out of the closet to anyone paying the slightest attention.

Not too many people were doing that just yet, however, although Sin After Sin did gradually win over new fans, scraped into the charts and would eventually earn a gold certification many years later. But by then, Judas Priest's third album had been overshadowed by ensuing successes like Stained Class, Hell Bent for Leather, British Steel, and a coterie of America-conquering '80s efforts.

Luckily, Priest fans are known for having a long memory and remember all too well that their heroes took a crucial few steps forward with Sin After Sin. Worldwide notoriety would have to wait, but Judas Priest were on their way.

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It's all the more surprising when you consider the success so many of them had by any other measure. 

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