HANDEL OPERA EARNS BRILLIANT TREATMENT

Composers go in and out of fashion at the drop of a baton, but George Frideric Handel's name stays steadily on the list of Top 5 classical composers. His monumental choral work ''The Messiah'' ensures it.

But to truly appreciate Handel's genius, listeners need to hear one of his 41 operas. Fortunately, a mini revival of Handel is in progress, helped along by a brilliant Boston Lyric Opera staging of ''Xerxes.''

One of his later operas, ''Xerxes'' (pronounced ''Zerk-sees'') is rarely produced, and hardly any complete recordings exist, despite the fact that it contains one of Handel's best-loved melodies. The tune is known as Handel's Largo, and generations of voice students have sung it in the original Italian as ''Ombra mai fu,'' an ode to, of all things, a tree.

Handel (1685-1759) was thoroughly immersed in Italian opera's dramatic themes and musical forms by the time he settled in England in 1712. He was also influenced by the cult of personality that grew up around celebrated male sopranos, many of whom were castrated as young boys to keep their high voices. Such singers were known as castrati. (The practice fell out of favor by the mid-19th century.) To perform Handel's operas today requires transposing the songs down into tenor or bass range, asking a tenor to use his falsetto range, or using a female soprano dressed as a man.

The latter option was taken by director Stephen Wadsworth and conductor Craig Smith for the Boston production. Lorraine Hunt made a regal King Xerxes, portraying him with a stern jaw, a boyish pout, and royal effusion. Hunt made the most of her breeches-and-waistcoat role to revel vocally in the part of a lovesick king who forces his attentions on the woman who loves his brother.

In ''Xerxes,'' Handel breaks with the Italian stand-and-declaim style and goes for character and comedy. The lonely king, his banished brother, the resolute fiancee, her scheming sister, and the goofy servant all come out of situations familiar from Italian and Shakespearean comedy.

Singers in the Boston Lyric production had an excellent grasp of Handel's baroque adornments. The music became swift daggers of emotion in the singers' hands. One hopes that, when the current Boston production ends on Sunday, more opera companies will take it up.