The final album by the Who's original lineup arrived on Aug. 21, 1978, as a product of its time.

This was three years after The Who by Numbers, which sounded like the band on autopilot at times. The Who had a lot to contend with, like punk rock, the electronics insurgence and, perhaps most importantly, a songwriter who seemed to be growing out of his band.

They were becoming somewhat archaic, following more than a decade of turning out perfectly tuned youth anthems and taking rock 'n' roll to operatic new heights. Punk had injected a tough, rebellious spirit into music, and guys like the arm-windmill-flailing Pete Townshend and chest-baring Roger Daltrey were seen as theatrical dinosaurs whose old-fashioned style had gone out with Nixon.

So, Townshend had something to prove on Who Are You, even if he didn't always sound fully committed to the work. He had used synthesizers in the past (see "Baba O'Riley" and "Won't Get Fooled Again," for starters), but here he loaded up on them, building songs on loops, riffs and melodies composed and laid out on them. He stacked them against elaborate string arrangements – he was also fighting off prog at the time – which give the tracks a heightened sense of importance.

An added level of guitar grit, a poke at the punks, was the final touch.

Listen to the Who's 'Who Are You'

The songs themselves stemmed from Townshend's abandoned Lifehouse project – which hugely inspired 1971's Who's Next – not always directly, but the symbolic theme of music as a lifeblood persisted below the surface. Together, these elements form the Who's final stand.

And in a way, the album unspools like a requiem for the band, the '70s and rock 'n' roll the way it used to be. Songs like the elegiac "Sister Disco," John Entwistle's "Trick of the Light" and the searing title track lay a solid foundation to what would be the original group's last hurrah.

Keith Moon died of an overdose about a month after the album's release. Oddly enough, he's pictured on the cover sitting behind a chair (so to disguise his alcohol-bloated stomach) labeled "Not to be taken away."

Who Are You made it to No. 2, eventually selling a couple million copies in the U.S. Along with Quadrophenia, it's the Who's highest-charting album. The title-cut lead single climbed to No. 14 – their best showing since "See Me, Feel Me" reached No. 12 in 1970. After Moon's death, it was another three years before the Who released another album, the soggy Face Dances. This time, the Who really did sound out of touch.

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