The latest CDs from Lil Jon & the East Side Boyz and the Ying Yang Twins, in fact, offer nothing new at all. Yet music fans who take a chance on these just-released offerings will never regard hip-hop the same way again.

Lil Jon's "Crunk Juice" and the Twins' "United State of Atlanta," both top-10 CDs from recent months, have been "chopped and screwed," a musical style in which a DJ slows down a recording -- pitch, tone and all -- until it oozes out of the speakers at a molasses-like flow.

The syrupy sound originated in the early 1990s in Houston, pioneered by DJ Screw, who stumbled upon it while fiddling around with his turntable. Screw died in 2000, but his invention has lived on, now named in his honor, and maintains a niche following throughout the South.

Now the mastermind of the sound is Michael "5000" Watts, the Houston producer who remixed both of these CDs. He employs the techniques of a throwback party DJ -- but in half-time.

The appeal of the sound is particularly apparent on the remix of Lil Jon's album. The King of Crunk's minimalist, bone-rattling, bass-heavy Southern funk now creates a rumbling rhythm bed that is deliciously hypnotic.

Chopped and screwed, a track like "What U Gon' Do" eases the aggressive characteristics of Lil Jon's rowdy anthem, flipping an assailing fight song driven by belligerent chants into a steady, head-bobbing jam eliciting echoes of late-1970s Jamaican dub. "Lovers & Friends," a pedantic love song, now takes on dreamier, nostalgic tones, with guests Usher and Ludacris both sounding as if they're singing an old-school rhythm & blues ballad.

Watts's style is to work the album tracks into a continuous mix and strategically repeat and rearrange things (the "chop") to create syncopated sub-rhythms that compensate for the slack of slower tunes. And so the best remixed Ying Yang Twins songs are its hip-hop/R&B collaborations, especially "Put That Thang Down" with singer Teedra Moses.

These songs' new mix accentuate the nuances often lost in the pursuit of cultivating a pop hit: deeper rhythms, sweet melodies and more transparent lyrical passages.

Watts gives the Ying Yang Twins' biggest hit, "Wait (The Whisper Song)," another personality altogether. He smears the group's raunchy, cooed vocals into an indecipherable harmony (considering the vulgarity of the lyrics, this isn't a bad thing), and double-times the sparse bass hits to create a meditative instrumental not unlike a raga.

That Watts could salvage anything musical out of the Ying Yang Twins is both a tribute to his inimitable skill and the chopped-and-screwed style .