Two contrasting concerts show best face of D.C. choral scene

I was not thrilled to discover that Washington's three largest choruses had all scheduled their final performances of the season on Sunday; and I was particularly unexcited about hearing two of them on the same day. I only state this to demonstrate that a good concert can convert even the grouchiest critic, because both concerts -- the Cathedral Choral Society's performance of opera scenes and choruses at the National Cathedral in the afternoon and the Choral Arts Society's "Carmina Burana" at t...