"Last summer," a Georgetown merchant said recently, "the street musicians were freaky and dirty and played loud rock.

"This summer," she said, "the kids on the corners are playing more classical music and they seem more sophisticated. Rock and roll just seems out of place in Georgetown to me.

"Classical doesn't."

Traditionally heard in concert halls at the Kennedy Center or at posh outdoor theaters like Wolf Trap, classical music has suddenly taken to the streets of Washington.

On any given weekend evening, as these steamy days of August slip by, classical musicians - ranging from violin soloists to string quartets - can be heard on sidewalks and street corners in Georgetown, rhapsodically performing music from the baroque to Beethoven.

Their arrival there this summer is in striking contrast to the traditional genre of street music in Washington. In summers past, bluegrass, folk, rock and roll and to some extent, gospel have been the predominant styles.

Those styles can still be heard, of course, at the corner of 9th and F Streets, NW, blind gospel singer William Hines has been performing an extended 13-year engagement, while folk musicians occasionally can be heard in fron of government buildings like the National Portrait Gallery.

But it is in Georgetown this summer that merchants, shoppers, tourists and curious onlookers are hearing more and more Bach and less and less Baez. Last Friday evening, for instance, there were no less than five classical groups performing out of an estimated total of seven companies of musicians playing on the stoops and streets of Georgetown.

Ralph Greenblatt, a 24-year-old flutist from Rockville arrived at the M Street entrance to Canal Square, a Georgetown office and shopping complex, early Friday evening.

He and two fellow students of music at Montgomery College, who together form a classical music trio, usually play at the Canal Square entrance, beneath in alcove, on weekends. The site is considered a choice spot by street musicians because of its acoustics, pedestrian traffic and rain protection; Greenblatt always tries to arrive by 5 or 6 p.m. in order to stake his claim to the site for the evening.

This night, though, he found rock guitarist Skip Breitmeyer ahead of him.

"Will you be playing long?" Greenblatt asked Breitmeyer, who sat barefoot in bluejeans and a T-shirt on the brick floor, listlessly strumming an old Beatles tune.

"I don't know, man," Breitmayer replied, "can't say."

"I'd like to know," the flutist continued, "because me and my group have played here every weekend since spring. This is the way we earn a living."

Greenblatt looked at Breitmeyer's open quitar case and noticed that it contained no money.

"Look," he said, "you play rock and roll. We play classical music and make money at it because the people who come around here are the wealthier types who tend to get into classical.

"You can make money on the streets," Greenblatt said, pointing outside toward M Street, "because street people are more likely to get into rock and roll."

"Just the same," Breitmeyer said, tuning his guitar, "I'd rather stay here."

After Greenblatt left, reluctantly conceding his usual spot to to the guitarist, Breitmeyer lit a cigarette and explained his stubborness.

"I've hitchhiked all over the country," he said, looking over blue tinted sun glasses and shaking his long blond hair out of his eyes, "and played on streets in the East and West. I'm able to eat because I play, but I'm able to eat because I play, but I'm mainly into having a good time. I dig having people clap and stomp their feet to my music.

"They usually don't pay much," he said, pointing at his empty guitar case, "but they enjoy the music. I didn't want to give this spot up to that guy because those classical people are into making profits. They're like polished professionals, and take the fun out of the streets.

"Besides," he said, flicking an ash into the air, "they're so damn snotty."

On the corner of Wisconsin Avenue and Prospect Street NW, in front of the Carriage House restaurant, Chris Scroggins sat with her partner, Paul Glenn, played a few notes on his cello.

They placed Beethoven sheet music on metal stands in front of them, while evening shoppers and tourists passed back and forth, and trucks and cars rolled by on Wisconsin.

"It's the first night we've ever played on the streets," said Glenn, who works as a satellite programmer for NASA, "and we're kind of nervous."

Scroggins, an 18-year-old music student at the University of Maryland, said "let's do it," and suddenly the humid air was filled with strains of Beethoven. A few of the pedestrians laughed as they walked by, others smiled in appreciation, but some stopped to listen.

A drunk, who arrived and acted for a time as an impromptu conductor, suddenly staggered away, muttering something about country-Western fiddles. A family of five stopped to gape at the duo, quietly eating ice cream from paper cups.

A young Bohemian, holding a flute case under his arm, listened for a while, smiled, applauded loudly and then dropped a $5 bill into the green velvet interior of Glenn's cello case before walking away.

Two hours later, after performing a number of Beethoven and Ravel sonatas, Scroggins and Glenn were much more relaxed. They had earned close to $40.

"This is great," said Scroggins, who has been playing the violin for 10 years. "I always wanted to play in an orchestra some day. I may have found something better."

At 8 p.m., Ralph Greenblatt returned with the two other musicians in his classical trio and luckily found that Breitmeyer had packed up his guitar and vacated the Canal Square site.

"We really need this spot," Greenblatt said. "The people that tend to shop in and around the square are more cultured and wealthy than the ordinary street types. On a good night each of us can pull in 80 bucks a piece.

"It's getting harder and harder to get this spot, though," he said. "Everybody is beginning to realize how good it is. And they're breaking all kinds of unwritten laws of street music. A few weeks ago these five conga drum players set up right here next to us and started pounding away in the middle of one of our pieces.

"Stuff like that's been happening too much lately," he said, returning to his group underneath the alcove and preparing to begin a rendition of Bach. "I guess rock and rollers are just jealous that classical can be so successful."

By 10 p.m. 18-year-old Chris Kranyak of Rockville had been playing his violin in Canal Square for nearly two hours. A music student at the university of Connecticut, Kranyak has been earning money the last four summers playing violin solos in the square.

"It's a good money," he said, after finishing a Vivaldi piece to the appaluse of about a dozen listeners in the square. "I can't stand this humidity, though. It's good for the violin, but sure is torture for me.

"It should pick up soon," he continued, as he picked up a sheet of Beethoven music and looked anxiously toward the entrance to the Port-O-Georgetown restaurant. "The restaurant's full and should empty soon."

Suddenly, it did and the square was filled with tourists from Pennsylvania. Kranyak, just as suddenly, cut Beethoven to an abrupt end and launched his bow into a lively offering of "Scarborough Fair," a folk ballad.

Several couples in the delegation of tourists began to dance to Kranyak's music delighting onlookers. After the piece was concluded several bills were dropped into the musician's open violin case, and Kranyak bowed to the applause of his audience.

"That's the kind of music I have to play if I want to make money," he said, sitting down on a bench in the middle of the square and rummaging through his collection of sheet music. "People like to hear recognizable tunes, so, to please them, I play stuff like 'Yesterday' and The Way We Were,' even though I like the classics better."

A street guitarist sauntered in then, carrying a chair under his area. he asked Kranyak if he was finished for the night.

The violinist shook his head and walked slowly to his metal music stand. With his violin perched under his chin. Kranyak tapped his bow light for several minutes on the stand in front of him, trying to decide what to play next.

"What're you doing, maestro?" the guitarist asked Kranyak impatiently. "Waiting for the lights to dim?"