Avant-keyboardist Margaret Leng Tan is not a collaborator—she prefers to perform alone, as she admitted during her 2006 visit to Seattle. "Really?" I asked her then. "If the Kronos Quartet called and commissioned a quintet for them and you, you'd say no?" She would. Her solitary explorations have taken two paths: She's the world's foremost toy-piano virtuoso, and hearing her, once you get past your initial giggles, you'll be amazed at the captivating expressivity Tan can draw from the mechanically tinkling little contraption. She also plays the standard concert grand, but from the inside: scraping, brushing, plucking, thumping, and doing a thousand other things to its strings, while also attaching myriad objects to them to alter their tone color. Carrying on the legacies of Henry Cowell (1897–1965) and John Cage (1912–92), who pioneered these techniques and exploded what can be done with the instrument, Tan will present "Breaking the Sound Barrier: The New Piano," a lecture-recital in UW's Brechemin Auditorium. ("New" here is a relative term: Cowell's earliest experiments—playing a wide swath of keys with the forearm, for example, to create a haunting, gonglike boooooooom—date from the 1910s.) Following this is a screening of a charming documentary on Tan's life and work, Sorceress of the New Piano; her Thursday concert, in Meany Hall's Studio Theater, will also include George Crumb's 1973 Makrokosmos for amplified piano.