by Geoff Orens 　　Prefuse 73 is the alias of Scott Herren, an experimental hip-hop producer whose material often features MCs buried in the mix to become more a part of the sonic texture than a focal point. Herren began his career working in commercial studios in Atlanta, but later went on to more experimental work. His first record under the Prefuse name, Vocal Studies + Uprock Narratives, not only buried but cut up and spliced raps as well as allowing some more straightforward vocals from several MCs. The 2003 follow-up, One Word Extinguisher, carried on in a similar vein. That same year, Warp released Extinguished: Outtakes -- a fascinating EP of beats and samples that ran through 23 tracks in about 35 minutes. 　　 　　Surrounded by Silence, the proper successor to One Word Extinguisher, was released in March of 2005, featuring collaborations with rappers Ghostface and Aesop Rock, plus Blonde Redhead and EL-P. Three months later, an EP of recordings made with the band the Books appeared, titled Reads the Books. The next Prefuse record, 2006's Security Screenings, was relatively collaboration-free; it featured only two guests, Four Tet's Kieran Hebden and Tunde Adebimpe from TV on the Radio. Preparations, featuring Battles drummer John Stanier on one track, followed in 2007. Herren has also worked under his own name and that of Savath + Savalas and Delarosa & Asora.