Now in its 15th year, the Newberry Consort has lived up to the high expectations that would attend any group founded by Mary Springfels. The superlative violist da gamba and musicologist came to Chicago in the early 80s and soon persuaded the Newberry Library to back this period-instrument ensemble; since then the Consort has become a magnet for practitioners and scholars of Baroque and Renaissance music from around the world. In return for the library's sponsorship, she's pored over its trove of early-music manuscripts, transcribing many of them into notation intelligible to modern performers--and as a result, her group has played pieces from just about every historical period and in almost every major style, ranging in their places of origin from the British Isles to the mountains of eastern Europe. The Newberry Consort aims to entertain as well as edify, and the casual intimacy of its concerts puts newcomers to early music at ease--Springfels and company share interesting facts about their program during the performance, without presuming too much knowledge on the audience's part. And though music from the Renaissance repertoire can be an endurance test when rendered insensitively--much of it is very repetitive or low-key by contemporary standards--I have yet to attend a Newberry Consort recital that didn't hold my interest from beginning to end. The core members, presently Springfels, violinist David Douglass, countertenor Drew Minter, and soprano Ellen Hargis, will be joined for this Sunday's holiday concert by Korean-born violinist Jin Kim, and thankfully there isn't a single well-worn Christmas carol on the program. Two of the featured composers, Chiara Margarita Cozzolani and Rosa Giacinta Badalla, were nuns from wealthy families who led cloistered lives in Milan in the 17th and early 18th centuries yet gained international fame for their music and singing. The Consort will perform a Christmas cantata by each; Badalla's piece, according to Springfels, "creates a particularly vivid, wintry pastoral setting for the Nativity." Vocal and instrumental works by Tarquinio Merula, Christopher Simpson, Dietrich Buxtehude, and Christian Geist round out this 17th-century sampler, which concludes with an anonymous English ballad that "calls for putting aside old enmities in honor of the season." Sunday, December 23, 3 PM, Ruggles Hall, Newberry Library, 60 W. Walton; 312-255-3700.