Chamber music can conjure images of drowsy oldsters with English accents gumming on caviar, but that’s unfair. Not every ensemble must play mincing renditions of the Trout Quintet. Take the trailblazing string quartet Brooklyn Rider. A performance from these four men can sound invigorating, edgy, and improvisational, as they saw on their strings and draw on influences as wide as folk and rock. In fact, these gents often collaborate with musicians who earned their fame well outside the most broadly drawn borders of “classical” music.