At their worst, mash-ups can come across as patronizing in-jokes, elbowing your sternum at how totally way-out crazy it is that two pieces of music from disparate genres can actually coexist in the same space. The lazier bootleg artists stick to a predictable formula: Look for the most incongruous styles you can beatmatch, give the resulting track a cringeworthy portmanteau of a title ("Smells Like [insert Britney Spears reference here]"), and jam that culture for all it's worth. Maybe that's why mash-ups fell out of favor after their Boom Selection-fueled circa-2002 heyday: The idea worked a lot better when it wasn't the three-minute, 192 kbps version of a rimshot.

There's reason enough to assume that Dirty South Dance is a similarly ironic venture: regardless of how seriously you take boutique propagandist Shepard "Obey" Fairey, his "Easter Bunny bling" cover design screams forced whimsy, and the mix's idea to combine last year's crunk and comparatively obscure electro-house theoretically smacks of hipster goonery. (If the name "Tha Pumpsta" hasn't yet dislodged itself from your memory banks and forced some bile into your throat, I'll give you a minute.) The (stereo)typical audience for this type of thing tends to skew towards the superficially trendy, and the first minutes of the mix-- Lil Jon yelling over gleeful, chirpy Euro-scuzz electro-- might elicit either baffled amusement or embarrassed revulsion, depending on how tired you are of club kids screwing around with crunk.

But if A-Trak is prone to a certain level of aesthetic smartassery, he's no charlatan. In the decade since he won the 1997 DMC World DJ Championship at a prodigious 15 years of age, he's turned the art of turntablism back toward its original party-rocking focus-- the dude can scratch and beat-juggle, but he's just as skilled at maintaining momentum and crafting seamless segues. And while listeners might look at Dirty South Dance on paper and formulate some sort of genre hierarchy-driven classism in its blueprint, the mix works simply because it largely pretends that line doesn't exist. (And considering how Tag Team's "Whoomp! (There It Is)" turned Kano's 1980 Italo-disco track "I'm Ready" into one of the first nationally massive Southern bounce hits, it's not that much of a stretch.)

Most of the blends are effective to the point of essentially supplanting the original tenor of the instrumental portions, and while A-Trak tends to tweak the rap a cappellas in order to better fit the rhythms, the best ones still feel like dance on the Dirty South's terms. The cartoon ghettotech Peanut Butter Wolf mix of Baron Zen's "Turn Around"-- one of the more stilted moments on Stones Throw's Chrome Children comp-- sounds a lot more natural with Da Backwudz' unruly "I Don't Like the Look of It (Oompa)" laid over it. And Rick Ross' "Hustlin'" is fused to Simian Mobile Disco's "Hustler"-- a matchup obvious enough that Cadence Weapon attempted it sometime last year, though A-Trak's take (titled, yeah, "Hustlin' Hustler") does more to trim the empty spaces from Ross' vocal and heightens the velocity of the SMD original. The result is that each beat of its amped-up electro rhythm turns into a foil for Ross' deceptively-calm voice to ricochet off.

But while most of the cuts tend to lean a bit more heavily towards the rhythms of the indie-dance set and modify the vocals accordingly, they hardly detract from the MCs' original qualities. Yung Joc's "It's Goin' Down"'s is stretched out over the throbbing raver punk of Soulwax "E-Talking (Nite Version)", his cadence drawn out to a relaxed drawl that makes his declaration "err'body loves me/ I'm so fly" sound twice as smooth as the original. Rich Boy's "Throw Some D's" is turned into a halting but forceful hip-house vocal to match Para One's remix of Daft Punk's "Prime Time of Your Life". And Clipse's "Wamp Wamp" is scattered frenetically across Alex Gopher's retro-electro "Motorcycle", their tempo (and the Neptunes' lingering steel drum hook) ratcheted up to Bambaataa velocity. (One aside: A-Trak, who got his first turntable as a bar mitzvah gift, noticeably omits Malice's "It cools to a tight wad/ The Pyrex is Jewish" verse.)

Dirty South Dance isn't an entirely accurate title, though, and there's a decent-sized glut of international debris that breaks the theme. And aside from the Pack's Bay Area anthem "At the Club"-- with its glassy-eyed "in the club, I shake my ass/ At the party, I shake my ass" chorus sounding enough like a stereotypical deadpan electroclash chanteuse to feel right at home alongside Cassius' "Feeling for You"-- most of them push the mix out of focus. Gwen Stefani's dippy "disco Tetris" dud "Yummy" clashes against the disco Katamari Damacy of LCD Soundsystem's "Time to Get Away", French rappers TTC sneeringly sing-song their way through "Quitte La Piste" (which, to its benefit, features a synth hook that sounds like a Ducati exhaust hooked up to a pipe organ), and the mandated-by-law appearance from M.I.A. has her muttering "XR2" over a Giorgio Moroder track-- which sounds all right, but why should she be the one get all the Scarface quotes?

As if there was still any question that this techno shit belongs anywhere near hip-hop, A-Trak ends his mix with a good Q.E.D.-- naturally, it's Timbaland's beat for "My Love", which he lets fly at its own familiar pace for a moment before frantically juggling it and eventually cranking it up as fast as it'll go, transforming it into a dizzying explosion of breakbeat hardcore that sounds like the Prodigy circa 91. It's one of the most berserk codas you'll ever hear in a dance mix, but A-Trak knows well enough to bring that beat back down to its original pitch before switching the lights off. He may have just spent the last 50 minutes pairing off some unlikely artists, but he's too busy moving the crowd to smirk at the results.