New music rules New York this week. Tonight (Monday), the American Contemporary Music Ensemble will present a "21st-Century Schizoid Music" concert at Cornelia Street Café, with NewMusicBox's Frank Oteri as host. Program runs gamut from Ives' venerable Second Quartet to Reich's New York Counterpoint to Nico Muhly's Keep In Touch, a superb new piece for viola and electronics featuring the recorded voice of Antony from Antony & The Johnsons. On Tuesday and Wednesday the Ensemble Intercontemporain plays in Lincoln Center's "Sound Projections" series under the direction of Jonathan Nott. Tuesday's concert is the local premiere of Benedict Mason's ChaplinOperas, wild live music to accompany three classic Chaplin shorts. (Don't miss Allan Kozinn's Mason profile in the Times.) Wednesday's show combines Ligeti's dreamlike Piano Concerto with Wolfgang Rihm's ferocious Jagden und Formen. On Thursday, NOW Ensemble plays at the Church of Christ and St. Stephen's. On Friday the Line C3 percussion group appears at Tenri Cultural Institute; more Muhly (Ta and Clap), more Reich (Drumming Part 1). And on Sunday the New York Youth Symphony presents the premiere of Today and Everyday by Judd Greenstein, who has already been touted in this space.