The Harvard Band started off the latest chapter of "Drumbeats and Song" with a program of marches, medleys and the best band music in the country. After this predictably excellent hors d'oeuvre came a main course that was a delightful surprise.

It is incredible that a show--and an amateur one to boot--could maintain so high a level of music and lyrics as I saw last night. And yet Eiffel Trifle goes from one high point to the next with the most minor of sags. Only an occasional bit of mawkish and misfitting dialogue mars a generally amusing book and completely wonderful words and music.

Among a field of heroes, Jesse Richard Barnet ranks the highest for producing the finest set of lyrics and the liveliest score to hit Boston this season--barring only Guys and Dolls. To any local theatre goer, inured to the relative inferiority of non-professional musicals, Barnet's work is just amazing. It is seriously the equal of all but the apex in professional writing, and it is steady in its near perfection. Not one of the songs in the show is less than very good, and several are magnificent. "All About Love," "A Word With You," and "Incognito" inspire cheers from the audience and top performances from the cast.

The book by John Addey and Harvey McGregor does falter in spots, but the stickier lines lead into songs, and are necessary for shifting the mood from comedy to the romantic. Besides, anything that ushers Barnet on stage is forgiven many failings.

Martin Meyers gets the most laughs, and deserves most of them, with his gape-mouthed version of a farm boy at Harvard. Robert Rosenberger and Lee Jefferies do the romantic bits with fervor and slightly weak voices, managing, above all, to seem sincere and attractive. Barbara Williams' distinctly frail voice was backed with charm and bounce for "Incognito"--her only singing chore. And her acting, when not rushed, was very competent. For a chorus of "All About Love," Ellen McHugh showed perhaps the most talent for comedy in the cast, closely followed by Shiela Flaherty's board rendition of "When the Postman Rings the Bell With New Yorker."

Too many of those with smaller parts, including the lissome kickline, did such creditable jobs that they cannot be named in a short review. It is a shame that "Drumbeats" is not running longer.