BY MELISSA RUGGIERI/AJC Music Scene

It’s a unique enough scenario that a former couple in the same industry maintains a close friendship for 50 years.

It’s even more unbelievable that these long-ago lovebirds would decide now, in the sunset of their careers, to record an album together.

And it’s downright implausible that the album release would be prefaced by a tour featuring the two legendary musicians sharing the stage for the majority of the night.

 Stills broke out some Buffalo Springfield and CSN songs during the set. Photo: Melissa Ruggieri/AJC

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

But lucky for us that Stephen Stills and Judy Collins are defying convention.

The album from the twosome, “Everybody Knows,” will arrive Sept. 22. Their tour, which kicked off last month and rolls deep into fall, is testament to their symbiotic musical relationship and enduring friendship.

Both were on display for an hour and 45 minutes at Atlanta Symphony Hall Wednesday night as Stills and Collins roadtripped down memory lane and offered a few peeks at the upcoming release.

It wasn’t always perfect. Their opening cover of Traveling Wilburys’ “Handle With Care” veered off key and throughout the show, Stills’ guitar was placed too high in the mix and often overpowered to a cringing degree.

But his shaggy vocals were a warm, gruff complement to Collins’ pure, graceful voice and they harmonized adeptly on “River of Gold” and Bob Dylan’s “Girl from the North Country.”

With her black boots and puff of platinum hair, Collins defies her age of 78. She’s also an engaging storyteller (as is Stills) who chatted while she tuned her guitar and, before delving into the mesmerizing “Everybody Knows,” written by her lifelong friend Leonard Cohen, deftly delivered the line, “Leonard was so smart. He had the good sense to die the morning of the election.”

Stills, 72, and Collins shared the stage with their trio of backing musicians, including pianist and musical director Russell Walden. Each also offered brief solo performances – a loose “Treetop Flyer” for Stills and the forever-poignant “Both Sides Now” for Collins.

Collins again paid tribute to Cohen with a sparse, lovely piano-laden “Suzanne,” showcasing a voice that is undiminished by time.

 Collins displayed a flawless voice. Photo: Melissa Ruggieri/AJC

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

While the show hummed along on a mellow vibe, there was never a lull. “Chelsea Morning,” another Joni Mitchell composition that shares equal popularity with Collins’ version, pleasantly pulsed, while the delicate guitar notes plucked by Stills during “For What It’s Worth” prompted the crowd to hoot in recognition. Stills saved his fiercest guitar work for that song and “Bluebird,” during which he delivered a blistering solo.

In another nod to their past, Stills and Collins reserved the encore as the ideal placement for their songs about each other.

“The secret to our chemistry is that we married other people,” Stills joked.

“Houses,” which Collins reminded she wrote for Stills after their romance, unfolded as a stunning musical poem, while his song for his blue-eyed onetime love needed no introduction.

Stills and Collins raked their acoustic guitars during the intro to the Crosby, Stills & Nash classic “Suite: Judy Blue Eyes,” and soon the crowd, itching to participate, leapt to their feet to “do do do do do” along.

Who would have ever thought the day would come when Collins would be on tour singing a song written about her with the guy who crafted it?

Chalk up another improbability come true.

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