Jeannette Sorrell and Apollo’s Fire had a major hit with their high-class-folk-music album “Come to the River: An Early American Gathering.” Now they offer “Sacrum Mysterium: A Celtic Christmas Vespers” (Avie AV2269; 1 CD, 1 DVD), which mixes sacred and secular music from the Celtic tradition (mostly Scots and Irish, with a touch of Manx and Breton) in a charming musical mulligan stew.

Soprano Meredith Hall adapts to all the styles (and most of the accents), singing with sweet, clear tones; she’s well-supported by Sorrell, the choir and orchestra. The album’s essence may be found in the transition from a chant from the Vespers of St. Kentigern, patron saint of Glasgow, which starts in solemnity and then, in the alleluia, turns rollicking.