For the American composer Nico Muhly (b1981) English choral music is a dominant influence. So too is Philip Glass (b1937), whose music Muhly first discovered as a college freshman, later working for him as copyist and sequencer for his film scores. They remain friends, colleagues and Manhattanites. This disc of music for two violins, agilely played by Angela and Jennifer Chun, highlights their strongly individual voices. Muhly’s Four Studies (2014) are transparent explorations in counterpoint (listen for the composer providing keyboard drone). Glass’s Mad Rush (1979) and In the Summer (1993, transcribed by the Chuns in 2014) carry his trademark arpeggiated patterns and ever unfolding melodies, which here take on a silvery, high-violin hue.