It's a great idea to harmonize the world, as Harmony International's motto suggests, and no better way to do so than in four-part barbershop harmony.

Demonstrating the versatility of that language, America met Scotland and Sweden comfortably Tuesday night at Symphony Hall, each dealing fluently and comfortably in the swingy rhythms and synchronized gestures of the style, and pleasing the capacity audience, who found several opportunities to rise to their feet in appreciation.Utah's own Mountain Jubilee Chorus (formerly Bountiful Sweet Adelines) entertained, and under Tori Postma's direction they came across like the champions they are. Their red sequined dresses with floating scarves on the skirts looked great, the blend of voices was smooth and mellow, and their routines were catchy and attractive, with a small dancing chorus in front leading the way.

They pleased with "O You Beautiful Doll," a heartfelt "When I Fall in Love," a jivey "Breaking Up is Hard to Do" with everyone on the move, and jazzy "Manhattan Transfer." "From the First Hello to the Last Goodbye" served as a final farewell to three members killed in a plane crash last spring, on the way to compete in Denver.

The Aberdeen, Scotland Chorus demonstrated anew the charm of highland lassies - of all ages. Their white blouses and long tartans immediately suggested that their way with the barbershop mannerisms would be different, and their style, though authentic, had a fresh and unsophisticated flavor.

With sweet voices and clear diction, they first sang in straight choral style an original march about coming to America, and "Where the Heather Meets the Sea." In barbershop style they presented "My Ain Folk" and a lovable little ballad, "Operator, Get Me Jesus." A pipe and drum interlude by the Salt Lake Scots and the hymn "Amazing Grace" with audience participation completed the Scottish segment.

Last year's quartet champions, the Growing Girls from Sweden, justified their laurels (and tiaras as "Queens of Harmony") with a sequence of songs whose style and accent could hardly be distinguished from their American counterparts. Especially noteworthy were the wistful "Where is Love" and "Undecided."

Adding a little masculine bass and tenor to the proceedings were the Second Edition, 1989 winners at the competition of the Society for the Preservation and Encouragement of Barbershop Quartet Singing in America. They were funny, spirited and musically irreproachable in "Alexander's Ragtime Band," "Strike Up the Band," and a smooth, cool "Sweet Georgia Brown."

The two quartets joined for some mixed harmony in "Misty," "Let There be Peace on Earth," and the droll "Baby, You Can Drive My Car."

The Showtime Quartet, cheerful and glamourous troupers from Florida warmed up the audience with such numbers as a triple-tonguing auctioneer's song, a cute rock 'n' roll number "I'm a Blond," and the nostalgic "There's a Place for Us" (well-timed to observe the passing of its composer, Leonard Bernstein). Not least, Ann Gooch amused the crowd with her witty comments and many costume changes.