Hear Haydn perfect the classical string quartet, Brahms pay tribute to Bach, and Bartók surprise and delight. If Haydn was the father of the string quartet, his “Sunrise”—nicknamed for the first violin’s rising theme over a sustained chord—is one of his finest offspring. Brahms's expansive quartet is noteworthy for its crafty use of canons (a favorite Bach device), dash of Hungarian folk accents, and warm melodies. Bartók also makes use of folk music in his quartet’s Scherzo—this time Bulgarian—in a daredevil work of engrossing bravura.