NOTHING SO SO ABOUT THIS AMAZING NIGHT CELEBRATING ATLANTA MUSIC

The Atlanta record label that basically got itscommercial start with two teenagers named Chris who went by Kris Kross, started its 20th anniversary concert Saturday night with those same fashionably adventurous Chrises – one of whom still wears his jeans backwards.

And that would be an operative adverb in describing the three hour-plus, sold-out So So Def 20th Anniversary concert at the Fox Theatre: Still.

As So So Def R&B quartets Jagged Edge and Xscape – the latter of which was whittled down to Scott sisters LaTocha and Tamika – still surged with a soulful power a decade-plus after their debuts; and far more scarce among the chart-toppers in their genre today.

In the second set – where former So So Def A&R executive Lil Jontook on his one-time boss in a back and forth where the artists he’s signed and/or produced (Lil Scrappy, YoungBloodZ) went up againstJermaine Dupri’s (Bone Crusher, J-Kwon, Dem Franchise Boyz) – it could be said that judging from audience response, Jon won.

Still, it would be Dupri’s arm raised at the end of the night as the last set proved a series of exclamation points on the rapper-songwriter-label executive’s wide-ranging contributions.

There was So So Def signee Anthony Hamilton‘s brief but impactful two-song set where he ended up in the middle of the audience, immediately changing the tone of the show from rap-heavy to near-revival. Then surprise guestsMonica and Usher offered their own testimonials – in song, and afterwards.

“Jesus!” was all the usually-loquacious Dupri could say after Monica (signed to Atlanta musicmogul Dallas Austin‘s Rowdy Records) belted out his co-production, “Love All Over Me.” And Usher then shared with the audience that even though he signed to yet another Atlanta label (fellow Grammy-winning producers Antonio “L.A.” Reid and Kenneth “Babyface” Edmonds‘ LaFace Records), “it wasn’t really right until I started to get my No. 1′s with THIS man!”

“You’re a pioneer, homie,” declared Jay-Z, who could rightly claim such a title, himself. The entertainment multi-hyphenate – who collaborated with Dupri on one of his earliest commercial hits, 1998′s “Money Aint A Thang” – was part of a finale that ended with confetti, a stage ringed with enough music powers to fill a Grammy photo gallery, and in the end, Mariah Carey wheeling out a cake.

(Dupri co-produced Carey’s 2005 comeback single “We Belong Together”; one of her 18 No. 1 singles – the most by any female artist – and a record-holder for most the airplay in one day, still).