ISO Classical Christmas Scottish Rite Cathedral Dec. 17 Nicole Cabell, BBC Cardiff Singer of the World in 2005, performed with the ISO last weekend. At the time the Indianapolis Symphony Orchestra’s conductor laureate Raymond Leppard inaugurated his once-a-year Classical Christmas program in December 1998 when he was music director, no one knew how well it would be received, how long it would last. But he started with a bang, having engaged world-famous diva and archetypal prima donna Kathleen Battle. Though she gave certain orchestra personnel fits — she insisted on being switched to another hotel after midnight on her arrival day — Battle also delivered the greatest singing I’ve ever been privileged to witness, an almost life-altering event. After that concert, I started buying up all her recordings. Now, after eight years, this non-commercialized musical tribute to the Nativity has nicely matured under Leppard’s continuing direction while comfortably situated in the Scottish Rite’s Ballroom. Nearly all the seats are filled each year, and IU-Bloomington’s 20-singer choir, Apollo’s Voice — its name created specifically for that 1998 concert — has been making an annual appearance. And last Saturday, we heard a soprano voice on the cusp of greatness. Nicole Cabell, 28, BBC Cardiff Singer of the World in 2005, joined Leppard in one of his most interesting programs, mixing periods and styles, yet tying them together with a neat Christmas bow. First, Apollo’s Voice joined the reduced orchestra in Elgar’s ingratiating “A Christmas Greeting,” Op. 52, in Leppard’s own arrangement. Interestingly, the piece quotes Handel’s “Sinfonia pastorale” from his Messiah and comments on its theme. Then, a little later, we heard the “Sinfonia” as Handel wrote it, to introduce Messiah’s Christmas sequence from Part 1. In between, the choir offered an arrangement of Tchaikovsky’s familiar carol, “The Crown of Roses,” sometimes titled “Legend.” The orchestra then played Anton Arensky’s Variations on a Theme of Tchaikovsky, Op. 35. And what theme is that? Why it’s the one in “The Crown of Roses.” An effective coupling, though the strings showed occasional raggedness and intonation difficulties in the Arensky, problems seldom present in this event. Cabell was introduced during the Messiah excerpts. Possessing a full-bodied, well-projecting operatic soprano voice, this native Californian never crosses that boundary into the wobbly opulence so common among lesser singers. Her breath and vibrato control during the recitatives were astonishing enough — and she is young enough — that she seems destined to become one of our future international divas (hopefully without developing the “prima donna” complex shown by some). She’s already within a hair’s breadth (or a diva’s breath) of being there. Then, Apollo’s Voice and the orchestra delivered a captivating “Glory to God,” Handel’s first great Messiah chorus, followed by Cabell’s aria, “Rejoice Greatly, O Daughter of Zion” — beautifully capping the first half. Following intermission, Apollo’s Voice and the orchestra joined for “The Holy Boy” by John Ireland (1879-1962). Unexpectedly, ISO president and CEO Simon Crookall rose from his front-row-center seat, stepped on stage near the podium and added an “impromptu” tenor solo to the carol, showing a well-trained singing voice. Before the piece ended, he returned to his seat. It was an unexpected but tasteful touch. Another Leppard arrangement followed, “Lullaby for the Children of Christel House,” adapted from Joachim Raff’s (1822-1882) Octet for Strings, with Cabell joining the choir. Finally, Leppard offered his arrangement of a sequence of six traditional carols he calls Past Three O’Clock, for voice and orchestra. Some of these are interconnected with chimes, coupling Christmas color with Cabell’s superlative voice. The concert had to be encored with the universally loved “Sheep May Safely Graze” from Bach’s Cantata #208. And a Karen Moratz-Robin Peller flute duo provided luscious playing to complement Cabell’s luscious singing.