Carpe Diem Quartet (Karina Wetherbee)

The string quartet field is so crowded that every group is looking for some hook or cachet to set itself apart. A number of these quintessentially classical ensembles have branched out into pop, jazz, bluegrass and world music, with decidedly mixed results. Until Saturday evening, I had never heard a performance by one of these multilingual quartets where the classical repertoire was delivered at a level that was competitive with the finest traditional groups. But the Carpe Diem Quartet, appearing at the Dumbarton Church, was extraordinary.

The group was formed in 2004 and has gone through several personnel changes; its current lineup has been together less than a year. But the Carpe Diem’s performance of Beethoven’s Op. 59 No. 1 quartet (one of the hardest in the repertoire) had everything: care with dynamics and accents, timing of nuances, clarity of voice-leading and the widest ranges of character in each movement. This was one of the finest performances of a quartet standard I’ve heard in years.

And it was all the more remarkable because after the grinding blues of Bruce Wolosoff’s “5 O’Clock Shadow” and the dense passage-work of Joseph Kern’s “Iron City,” the Carpe Diem members had established only that they were fun and sexy — playing standing up, and taking full advantage of that physical freedom. But when it came time to deliver the most compositionally and emotionally complex music ever written, their imagination and instrumental skill took them to a different level entirely.

After intermission they offered “Fiddle Suite: Montana” by the group’s violist Korine Fujiwara. We’ve heard this sort of stuff before, from Mark O’Connor and others, but Fujiwara’s five-movement piece was expertly drawn and not a measure too long. Her own exuberant physicality drew her colleagues along in a winsome performance that had the staid Georgetown audience on its feet hooting and cheering. Among these contemporary quartets who speak in different tongues, the Carpe Diem is the best one out there.

Battey is a freelance writer.