2004 2000 Ravenswood's invaluable Experimental Sound Studio launched the Outer Ear Festival of Sound, a multivenue celebration of unconventional music and sound art that brought in important international performers, among them Peter Brötzmann, Jaap Blonk, Phill Niblock, the Sons of God, Laetitia Sonami, and Stuart Dempster. In 2010 economic shifts forced the organizers to reinvent the festival as the relatively modest year-round series Outer Ear, with most of its events in ESS's main studio. Though the 425-square-foot space seats just a few dozen, the sound quality is as lovely as you'd expect from a room where people record—the intimate gatherings of fans who attend these concerts bask in rich sonic detail, and most folks sit within ten or 15 feet of the performer. ESS continues to attract a fair number of internationally prominent artists to its coziest of rooms, including Michael Vorfeld, Lawrence English, Audrey Chen, and John Butcher, but the bulk of the bookings are Chicagoans (which was true of the old Outer Ear Festival of Sound as well). Given the bounty of fascinating experimentalists around these parts, though, none of the lineups is anything to sneeze at.