At a Chicago concert a few years back, Spanish sound artist FRANCISCO LOPEZ hung black curtains around his gear, turned off all the room lights, and distributed blindfolds to the audience–he treats visual stimulation of any kind as a distraction from the immersive experience of sound. His recordings, which are rarely named and usually minimally packaged–often without titles, credits, or album art of any kind–leap unpredictably from near silence to tympanum-scouring static. Lopez electronically magnifies, minimizes, or distorts a wide variety of audio sources–field recordings of rain forests and cityscapes, the noises of machinery, heavy-metal records–for maximum impact. Given the extreme dynamic range of his music and his interest in creating a controlled listening environment, it’s hardly surprising that he prefers digital media and hates rock clubs–but he’s breaking both his own rules here, playing a release party at the Bottle for his split LP with Michael Gendreau, who shares the bill. The album’s coming out on the local C.I.P. label, run by Blake Edwards of opening act Vertonen; Lopez’s side, “Untitled #185,” is built from meticulously arranged layers of vinyl surface noise. –Bill Meyer