Whether you regard the current electronica craze as just another music-industry trend or a genuine revolution in popular sound, one thing is for sure: It has given new life to the DJ. No longer relegated to the shadows of the stage or buried within the production notes on an album jacket, DJs have emerged as full-fledged solo artists who ply their craft hunched over two turntables, a mixer and a crate of laboriously scavenged vinyl.

Return of the D.J., Vol. II and Cold Krush Cuts – two DJ collections that showcase self-styled "turntablists" (or "turntable instrumentalists") from across the globe – offer object lessons in how to construct new realities out of other people's music. Billed as a double-disc Jamaican-style sound clash between Japan's DJ Krush and England's Coldcut and DJ Food, Cold Krush Cuts is really two separate hour-long mixes ("Back in the Base" and "Coldcut and DJ Food Fight") of tracks pillaged from the back catalog of leading U.K. trip-hop label Ninja Tune. The face-off between Coldcut and DJ Food is a dazzling primer in break-beat science. Not a second goes by when beats aren't tumbling, echoing or crackling across a colorful patchwork sky of hip-hop, jungle, techno, trip-hop, dub and ambient. DJ Krush's "Back in the Base" keeps things simpler and slower, sacrificing Coldcut's and DJ Food's aural sunbursts for stark, textured terrains populated by somnambulant grooves and wheezing turntable scratches.

Of course, the stylistic experimentation of Coldcut, DJ Food and DJ Krush has its roots in the old-school hip-hop art of cutting and scratching, and that's what's given center stage on Return of the D.J., Vol. II. Like the groundbreaking first volume, Vol. II (compiled by David Paul of the Bay Area rap 'zine The Bomb) is a dizzying celebration of quick-cut hip-hop turntable collage that brings together 16 rising DJs from places as far-flung as Phoenix and Finland. Appropriately, everything from KRS-One to Scooby Doo is devoured by the various DJs' nimble cross-fader choreography and scratch artistry.

Every DJ battle must have its winner, and on Return of the D.J., Vol. II, it's Z-Trip's "Rockstar." By mixing Public Enemy and Run-DMC with Black Sabbath, AC/DC and Van Halen (he even changes the fingering on "Eruption's" canonic guitar solo), Z-Trip hands rock its head on a vinyl platter and – like any good DJ – conjures a brave new world of sound out of the remains. (RS 757)

JOSH KUN