As TV Pow, the trio of Brent Gutzeit, Todd Carter, and Michael Hartman has always leaned toward the amorphous, testing the boundaries of what can be considered music. In the past this local group has electronically manipulated sounds from a variety of instruments–electric koto, drums, a 20-string steel “bass”–but on more recent stuff they’ve graduated to laptops and minidiscs. Computer musicians are everywhere these days, but TV Pow doesn’t sound interchangeable with any of those other Powerbook jockeys; its minimal approach, focusing on tiny improvised gestures and pure, almost nonmusical waveforms, can create the impression that you’re somehow listening to the imperceptible electromagnetic disturbances propagating through the room. On its two latest releases–Being Nice Is Funny (Mort aux Vaches) and Despite Ourselves (forthcoming on Fire Inc., the label operated by TV Pow’s sometime collaborators in the Icelandic group Stilluppsteypa)–the trio introduces splatters of white noise, abrasive crackles, and hollow ticks and pops over a steady high-frequency hum. That hum might drive a dog crazy, but it can also be strangely comforting: like a painter’s canvas, it provides a background for the other sounds to play over, a sort of aural surface instead of the void of digital black. Despite Ourselves also incorporates urban environmental recordings into its electronic soundscapes, a new direction for the group. A casual listener could mistake either of these CDs for a broken amplifier left turned on in the corner, but close listening reveals a multitude of well-crafted details. Wednesday, September 12, 10 PM, Empty Bottle, 1035 N. Western; 773-276-3600.