IN AN AGE of sophisticated cynicism, when romance is supposed to be dead, the idea of a violinist sawing "O Sole Mio" over an Italian dinner might sound like a bit much. Unless, of course, you're spending the evening at the Roma, a Washington tradition since 1920.

The charm of the Roma rests not so much in its relaxed, friendly service or the food, which modestly holds its own with most Italian restaurants around town. The Roma's lengthy menu extends itself beyond routine pasta and pizza with outstanding oysters oreganatti and a luscious linguinewith clam sauce, a house specialty recommended by the same waitress who later says, "Take your time. We're open until 1."

No, the best reason to pay a visit to Roma is not even the incongruous stuffed and mounted heads of boars, tigers, water buffalo and other animals killed on safari by Roma founder Frank Abbo.

What sets the Roma apart from other Italian restuarants is the music -- by pianist Herman Litzinger and Jim Diehl, a strolling violinist who has spent six years there serenading celebrities and playing catalyst for Cupid.

If anyone wears a smile for the pure love of music, it's Diehl. And from classical to country and western, he plays with an infectious attitude that permeates every song. You feel right at home, which, when you get right down to it, is the essence of the Roma experience."I come from a family that engendered hospitality," says Diehl. "And I use my music . . . to reach out to these people."

That all shows in his smooth tableside manner and engaging flourishes, as Diehl swoops into the first notes of a request before you can finish saying "virtuoso." His versions of "Somewhere Over the Rainbow," "As Time Goes By" and "Rhapsody in Blue" and selections from Wagner's "Tannhauser" stand a good chance of convincing you that the violin is the most beautiful instrument on earth and that romance isn't too terribly painful after all.

Of course, the partner of your dreams and an ample flow of Bolla Bardolino might help, too.

ROMA -- 3419 Connecticut Avenue NW. 363-6611. Open 11 a.m. to 1 a.m. daily; violinist and pianist perform Wednesday through Saturday from 7 to 11 p.m.; entrees are $8.50 to $13.50.