German sound artist Michael Vorfeld is primarily a percussionist, but rarely will he play a beat or fix a rhythm. On his recent recording with Reinhold Friedl, Au default du silence (Trente Oiseaux), Vorfeld's sounds hover above the scrapes and strums that Friedl generates by manipulating the inside of a piano. Vorfeld often bows his percussive devices (usually cymbals or other metal objects) to get long, wavering tones and high-pitched whinnies. He also works extensively as an installation artist, and he's in town for a piece with Belgian artist Maria Blondeel; their Wireless, Even Through Walls uses sound, light, and video to create a "dialogue between light-controlled square waves and percussion...accompanying or accompanied by a visual happening of light projected onto and into light, bright white and incandescently colored yellow, blue, or red." On Sunday they'll perform as part of the installation, Blondeel using a MIDI interface to translate light into sound, Vorfeld playing percussion and invented string instruments. They'll return to the site next Friday, joined by Chicago improvisers Robbie Hunsinger (double reeds) and Michael Colligan (reeds, invented instruments). Sunday, November 17, 7 PM, and next Friday, November 22, 8 PM, Hyde Park Art Center, 5307 S. Hyde Park; 773-784-0449.