The sanctuary of St. Cyril of Jerusalem Church resounded with the peal of a Dixieland trumpet playing "When the Saints Go Marching In." But in their entry down the aisle, the jubilant choir switched to the Greek liturgy:

Kyrie eleison, Christe eleison, Kyrie eleison.

This was anything but the "Missa Solemnis."

Written by Dale Jergenson, the Encino church's composer in residence, the "Dixieland Mass" is only one recent example of the continuing musical experimentation with the central act of Roman Catholic worship, the Mass. The folk guitar Masses of the 1960s look tame in comparison.

Although setting the Sanctus to the "Tiger Rag" was certainly new — "Hold that ti-GER" became "Sanc-tus, Sanc-TUS" — the inspiration driving Jergenson was not. It's the motivation behind the jazz "Missa Popularis" by Claus Bantzer, who recently conducted it in a Southern California tour, and Father Frank Perkovich's "Lamb of God" polka: finding innovative ways to attract worshipers.

And it apparently works, for the large congregation at St. Cyril, an otherwise traditional church, embraced the joyous pre-Lenten service without a whisper of heresy. As music director William Beck said beforehand: "A few people may be offended, and everyone else will have a good time."

Unlike a recent disco Mass performed by an Episcopal church in New York that featured men in sequined tank tops singing secular songs, including "Over the Rainbow," the Dixieland, jazz and polka Masses use sacred texts. And although "Popularis" is performed as a concert piece, the Dixieland and polka Masses are intended to be incorporated into the regular Catholic worship service.

As it says in Ecclesiastes, there is nothing new under the sun, and like the arm of an old metronome, composers over the last seven centuries have swung between straightforward interpretations and nontraditional settings of the service, especially what are known as the Ordinary portions: Kyrie, Gloria, Credo, Sanctus and Agnus Dei.

The constant theme in music and church history is that composers can't let well enough alone. One reason Roman Catholic clerics met at the Council of Trent from 1543 to 1563 was to confront the problem of Masses based on popular songs rather than sacred music.

One catchy tune from 15th century France, "L'Homme Arme," was used by dozens of composers, even if the original lyrics were less than saintly: "The armed man. The armed man is to be feared."

The clerics banished "all such music which, whether by the organ or in the singing, contains things that are lascivious or impure."

Even the greatest composers have raised eyebrows with their sacred works, including Mozart, who set "Lord have mercy" and "Christ have mercy" in counterpoint to each other in his Requiem, and Verdi, whose famous Requiem was originally criticized as being too operatic.

None of this weighs heavily on Jergenson, who studied composition with Roy Harris at UCLA and has written in such varied styles as 12-tone music and Pepsi jingles.

A few years ago, Jergenson said, he began writing a mainstream setting of the Mass, then got the idea of using a steel-drum band, which "has lots of Caribbean bounce." Then came a bagpipe Mass. And then, to honor New Orleans in the aftermath of Hurricane Katrina, the "Dixieland Mass."

Wearing a blue robe and white surplice, with Mardi Gras "throws" and a large cross around his neck, Jergenson said he has encountered criticism of his settings. A few people thought his earlier works had desecrated the Mass.

That raises a question: Can you make a noise unto the Lord that is too joyful?

Jergenson, his blue eyes twinkling, responded adamantly: "Never!"

A far more profound experience was the recent performance of Bantzer's introspective "Missa Popularis" at Pilgrim Lutheran Church in Santa Monica. It was part of a U.S. tour by the choir of St. John's Lutheran Church in Hamburg, Germany, that also included the Cathedral of Our Lady of the Angels.

Heavily influenced by the works of composers Keith Jarrett and Jan Garbarek, "Popularis" uses a quintet and large chorus and is at times highly improvised. But even here, centuries-old tradition continued. Employing a technique used by Renaissance and Baroque composers, "Popularis" employs "text painting" in which, for example, repeated notes show the "oneness" of God and leaps from low to high notes show a bridge between Earth and heaven.