The work of Olivia Block plays with or even erases the distinctions between kinds of sound: natural and man-made, acoustic and electronic, musical and incidental. The Texas native, who's lived in Chicago for about five years, assembles her microscopically detailed pieces by processing rehearsal recordings of acoustic ensembles—shifting, muting, or panning certain pitches, looping and filtering, cutting and pasting—and blending the results with environmental sounds like rustling grass, rattling stones, and fluttering breezes. Early in the one long composition that makes up her new CD, Mobius Fuse (Sedimental), electronic chirps insinuate themselves into a chorus of crickets; 12 minutes in, a series of massive brass chords cuts like an ocean liner through a bobbing flotilla of smaller sonic objects, which sound synthetic in origin but are actually the same chords run through her sampler. Still later an insistent patter, which at first might be falling rain, stiffens into a fiery crackle and then dissolves into decaying static. (I won't spoil the surprise ending.) For the local Experimental Sound Studio's second annual Outer Ear Festival of Sound, which runs through November 20, Block has written a new piece called Black Lake. It further explores the overlap between organic and inorganic sounds by requiring the musicians to act like machines—each member of a wind quintet repeats a brief pattern of a slightly different length, so that they slowly get out of sync, creating more and more complicated textures. Simultaneously four speakers, one in each corner of the hall, provide a simple rhythmic pulse that evolves into a densely layered array of electronic pitches, static, and processed field recordings. Also on the bill are a solo set by Dutch vocal acrobat Jaap Blonk and a duo between Blonk and German sound poet Michael Lentz. Friday, November 16, 8 PM, Galvin Auditorium, Sullivan Center, Loyola University, 6525 N. Sheridan; 773-784-0449.