Vienna Boys Choir (Lukas Beck/Lukas Beck)

The unexpected sound of boys barking and meowing in tune was but one of the many delightful moments during the Vienna Boys Choir's impressive holiday performance Sunday afternoon at George Mason University's Center for the Arts.

Finishing a 10-week U.S. tour, the choir presented a diverse program of works that not only celebrated the storied group's musical heritage but also showcased how quickly it is evolving. The driving force behind this year's 31-song celebration, including two onstage additions, and its engaging execution had everything to do with the touring choir's conductor, Manolo Cagnin. Named to his role in 2008, the Italian-born Cagnin directed in a captivating style emphasizing his singers' individuality. With his encouragement, each of the 25 choristers introduced himself to the audience, revealing a multitalented ensemble hailing from 16 countries.

Decked out in their hallmark sailor suits, the boys sang a Gregorian chant, "Veni creator spiritus," with perfect ensemble intonation. At the piano, Cagnin kicked off a rousing rendition of "O Fortuna" from Carl Orff's "Carmina Burana," complete with two of the boys playing gong and drum. Whether leading from the piano bench or conducting, the energetic Cagnin drew forth the boys' clarion voices, musicality and technique, notably in Heinz Kratochwil's "Jubilate Deo," a modern, a cappella setting of Psalm 100 written in 1976 for the Vienna.

Adriano Banchieri's "Capricciata a tre voci" triggered the choir's playful side, with the singers mimicking cats and dogs, while an adorable quartet dueled it out with gravelly meows in Rossini's "Duetto buffo per due gatti." The choir also excelled in two Johann Strauss pieces and a trio of dance rhythm-inspired songs featuring several members playing instruments.

Having sung in 25 states, the choristers were understandably fading at concert's end in a few holiday carols. But they rallied for a warm encore of Franz Biebl's "Ave Maria" and a rollicking take on the choir medley from "Sister Act."