Subtlety isn't the easiest virtue to convey on a concert stage, but that didn't faze Kate and Anna McGarrigle when they headlined the Beverly Theatre on Sunday night. A full decade after their debut album, the Montreal-based sisters filled a long, two-set show with low-key, understated and consistently winning songs that made their points quietly but surely.
The McGarrigles' music is an odd, charming blend: folk music that trades in acoustic guitars for accordions, fiddles and synthesizers; homey songs that often convey the uneasy menace lurking under family relationships. At its worst, the music can be too bland or too precious; more often, though, the intelligence of their lyrics and the delicate grace of their melodies win out.
Their low-key but funny personalities seemed as delicate and fragile as their music, but it's a mistake to jump to conclusions about two old pros. As the evening progressed, the McGarrigles and their five versatile backing musicians showed true grit on some full-bodied, almost Cajun-style dance tunes, and they displayed a wicked sense of humor between songs.