Make a list of the singers you'd expect to hear guesting on an album by Felix Burton and Simon Ratcliffe, the Brit producer-DJs known as Basement Jaxx, and 'N Sync's JC Chasez would probably not be on it. But here he is, on the Jaxx's third disc, humping the techno-dance whirlybird of ''Plug It In'' as if he wanted to make everyone forget Justin Timberlake's solo hits. Chasez's presence says much about the Jaxx's new ambitions. On the relentlessly forceful and aggressive Kish Kash, the duo sound as if they don't just want to get club kids in the house; they want to be stars, too.
The good news is that Burton and Ratcliffe approach this goal the way they've always approached their music: with frenetic eclecticism. The album's first half is sonic assault at its staggering best. Loopy-loop rhythms, 500-watt beats, hurtling strings, and obstinate female singers who belt rather than murmur make for the richest and most fervent music the Jaxx have ever made. Listening to ''Kish Kash'' is akin to charging through a multilevel club and being happily overwhelmed by the divergent styles booming out of each room. No one, including the Jaxx, could maintain such a pace, so it's not surprising when ''Kish Kash'' eventually gets bogged down in chilly drum-and-bass soul. But at a time of mix-and-match pop mania, the Jaxx's musical tossed salads remain fresh, not prepackaged.