The Portland Symphony Orchestra’s “Magic of Christmas” is more magical than ever his year, thanks to the talents of famed illusionist Lyn Dillies, who conjured music director Robert Moody out of an empty box before the opening medley.

A full house of children and adults at Friday’s opening-night concert at Merrill Auditorium was delighted with the illusions, which were not only mystifying but clever and entertaining. I wonder how many times Dillies has been accompanied by a full symphony orchestra.

They also heard some of the event’s best choral singing in recent memory, including a “Hallelujah” chorus so well rehearsed, played and sung by the “Magic of Christmas” Chorus that it reminded one of why so many amateur groups attempt to climb that peak year after year.

The most moving work of the evening was “Lux Aurumque” (Light and Gold) by Eric Whitacre, sung a cappella by the Windham Chamber Singers under the direction of Richard G. Nickerson.

I had read about the Windham group, which is internationally known, but had never heard them live. Their first selections, with the chorus and orchestra, “Christmas Bells are Ringing” and ” ‘Twas the Night Before Christmas,” were superior to most Christmas fare — pleasant to the ear but nothing extraordinary.

Then, after intermission, they sang the Whitacre piece and it was obvious what all the fuss was about. The absolutely perfect intervals in the semi-dissonant chords, the delineation of voices, the dynamic range, all combined to form a unique musical experience. Somehow the high soprano voice was made to sound like a crystal glass when rubbed along the rim. (Do try this at home this Christmas.)

“Lux Aurumque” is not for children, although they will probably enjoy the sheer sound of it, but for adults it is worth the price of admission all by itself.

The instrumental works by the orchestra were gorgeous as usual, beginning with a Christmas medley arranged by Robert Wendel, “Christmas a la Valse,” in which familiar songs and carols were all fitted into three-quarter time.

Also effective was the Pastorale from the Christmas Concerto (Concerto Grosso in G minor, Op. 6, No. 3) by Corelli, with a voice-over of the Christmas story according to St. Luke. I thought I detected a neologism in the King James Bible text, but hope I was wrong.

An arrangement of “Joy to the World,” with the full chorus, was crowded with incident, including some of the most powerful part signing I have heard from that group.

Some of my all-time favorite chestnuts, such as Grieg’s “In the Hall of the Mountain King,” the Mussorgsky-Ravel “Pictures at an Exhibition,” Overture to Mozart’s “The Impresario” and Bizet’s “Farandole,” were played as background to Dillies, adding more excitement to the illusions but effacing themselves a little in the process. Oh well, you can’t have everything.

The traditional “Sleigh Ride” and sing-along were up to their usual standards, with a little more wood-block hoof action in the former.

Both choruses and orchestra combined in the final “I Wish You Christmas” by John Rutter. My grandson, Jordan Seavey, proclaimed it all fun. He was asleep for part of the second half but awakened for more magic tricks and singing.

Christopher Hyde’s Classical Beat column appears in the Maine Sunday Telegram. He can be reached at:

classbeat@netscape.net