The most penetrating sound of Christmas is not bells on sleighs or the crinkle of packages being opened. The most glorious sound of the season is children’s voices lifted in song. This time of year, youth choruses around the world offer some of the finest highlights of the performance season. That’s true in Maine, too, where child singers around the state line up on stages to proclaim in song the joys of the holiday.

Bangor Area Children’s Choirs joined the Bangor Symphony Orchestra and the Robinson Ballet Company earlier this month to accompany instrumentalists in Tchaikovsky’s score for “The Nutcracker.” Their small voices gave a big sound to the music and charged the already magical story with dulcet tones.

The Bangor group does not perform again until Jan. 25, 2004, when both the treble choir and the youth chorale will sing at Minsky Recital Hall at the University of Maine in Orono.

Two highly recommendable groups, however, have holiday performances this weekend. The first is Eden Ensemble, the auditioned segment of Eden Children’s Chorus in Bar Harbor, in Gian Carlo Menotti’s one-act opera “Amahl and the Night Visitors,” 7 p.m. Dec. 19 and 20, and 2 p.m. Dec. 21 at The Grand Auditorium in Ellsworth.

The second is Maine Grand Opera’s MGO KiDZ making an appearance in a full-scale professional production of Giacomo Puccini’s “La Boheme,” 7:30 p.m. Dec. 19 and 3 p.m. Dec. 20 at the Camden Opera House.

Both operas are well known to American audiences. In fact, “Amahl,” the story of a poor shepherd boy, his mother and the Magi, is perhaps one of the most frequently performed operas of the 20th century. Sung in English, the piece was shaped to appeal to young voices and imaginations.

Eden Children’s Chorus and the Grand received a $3,000 grant from the Maine Community Foundation to mount this production. Fred Goldrich of Trenton is the artistic director and Robert Libbey, the Grand’s executive director and a frequent actor on local stages, is the stage director. It has been the job of Eden musical director Tom Wallace to shape his top singers to deliver the libretto with additional adult singers.

On a recent rehearsal in Bar Harbor, Wallace was working with the ensemble for a holiday concert that took place last weekend at Saint Saviour’s Church in Bar Harbor. His wife Lise was at the piano. Seven singers waited attentively for their leader’s direction, their eyes jockeying between his hands and their music books.

Wallace, who also is organist at Saint Saviour’s and director for both the Acadia Chorale Society and Mount Desert Summer Chorale, starts the singers in the younger group – more than a dozen third- to fifth-graders – and many go on to sing with the smaller, more advanced ensemble of about seven.

“For one thing, I love kids,” said Wallace, explaining his commitment to Eden. “For another thing, I know how much singing in a chorus meant to me at their age. Musically, I am able to do a lot more with them because they don’t have the same sense of limitation that adults have. And I live off their energy. I don’t think there’s anything more beautiful. I am so grateful for these kids.”

The singers expressed a similar confidence and gratitude about belonging to an all-children music group.

“I wouldn’t sing as much if I hadn’t been in the chorus and the ensemble,” said Thomas Van Gorder, a 14-year old who, as Amahl, is playing his first lead role. “I’m a much better singer now. Lots and lots of practicing and performing in the concerts help get me used to the nervousness. This has been a lot of responsibility for me but it is also really fun. All the other actors in the show are really good and really fun to work with, too.”

Karen Eisenhauer, founder and artistic director of Maine Grand Opera in Camden, established MGO KiDZ because, as a voice teacher in the Camden area, she recognized that there were many good voices and too few showcases for them. Also, as director of an opera company – and MGO is Maine’s only year-round professional opera troupe – it is necessary to have a children’s chorus prepared for the many works that call for young voices.

“There are so many talented kids in the area,” said Eisenhauer, who is also a professional singer. “When I go to the NATS [National Association of Teachers of Singing] competitions, I hear these kids from Calais and Fort Kent who just drop out of the sky – they are all looking for a platform. When there’s an audition for ‘Annie,’ and 100 little girls show up and only one is picked, you can see the need. So I wanted to give them the opportunity.”

In addition to directing the children in folk and choral music, Eisenhauer has dedicated time to training the group for “La Boheme” with Beaumont Glass, a professional opera director and coach to many famous singers, Janna Hymes-Bianchi, an internationally known conductor, and several featured guest soloists from outside the state. The opera is set at Christmastime, the tie-in to the season, but it also calls for that particular heightened sound of children.

“It’s a very pure tone that you get from children and it comes with no agenda,” said Eisenhauer, whose singers are between 8 and 16. “People want to call it angelic. It’s a treble voice, a high voice.”

Manan May, a 12-year old who has also performed in a previous MGO production of “The Magic Flute” and in her school chorus, said she wanted to join the chorus because she loves singing. At the first rehearsal, she found herself in a room of strangers whom, these days, she thinks of as her good friends.

But the real payoff is not solely social, added the seventh grader.

“I think I am a better singer than I was before I joined this group,” said Manan. “Even if I can’t hit a high note at school, I can hit it here.”

Both Eisenhauer and Wallace agree: Children should sing. And it is an axiom of their philosophies that no one should ever tell a child he or she cannot or should not sing.

“It’s a crime to discourage any child from singing because it is such a joy,” said Wallace.

The joy, of course, extends beyond the importance these choruses play in the lives of young people. There’s something about seeing children give themselves over to music, to stand with stillness, accomplishment and pride to share music with each other and with their communities. During this holiday season, in particular, the striking sound of smaller voices joined in song is, in so many ways, the very spirit of a holy day that takes as its most poignant symbol the image of a child.

For information about “Amahl and the Night Visitors” at the Grand Auditorium, call 667-9500. For information about “La Boheme” at the Camden Opera House, call 236-6156 or 230-1200.

For information about Bangor Area Children’s Choirs, call 947-2023; for Eden Children’s Chorus and Ensemble, call 288-8016; for Maine Grand Opera MGO KiDZ, call 230-1200.