Mozart's Allegro and Bach's Contrapunctus IX alternated with Mississippi, Maple Leaf and Junk Man rags. Two middle-aged women in polyester pants stepped to the ragtime and circled around, their handbags swinging wildly.

The sound turned baroque and a bystander remarked, "What is this, Kennedy Center?"

It was, in fact, the sidewalk in front of Weaver's Hardware Store near Wisconsin and M streets NW, where Brass Inc., a quintet of young District residents, has set up nearly every weekend since spring, choosing the open, illuminated patch of nighttime Georgetown so they can read their sheet music, clipped with clothespins against the breeze.

"The idea came with the spot; the spot came with the idea," said the group's trombonist and acknowledged leader, Wayne Powell, 20, a sophomore at Howard University and a graduate of D.C.'s Duke Ellington School of the Arts.

Before he formed the ensemble in mid-May, Powell played alone in front of the hardware store. Perhaps there was a subconscious attraction: Reflections of the group's instruments and gold-lettered T-shirts flashed in the hardware shop's pane glass window, and the display inside, a porcelain sink with brass fixtures, shined right back.

For Powell and the others -- Donna Loman, 20, a Howard junior; Byron Bryson, 19, a Howard sophomore; Kevin Dines, 18, an Ohio State University freshman; and James Poindexter, 17, Loman's cousin and a senior at Woodrow Wilson High School in Northwest -- the quintet was a good way to spend the summer.

They usually played Friday evenings, Saturday if it rained, raking in about $150 on an average night, $250 to $275 on a "really good" one. They played mostly baroque and ragtime and were rewarded with more crisp bills than coins by free-spending weekend crowds looking for fun and entertainment.

During a recent performance, the quintet's members took a break, and some left to buy soda and fried chicken. But slowly strolling passers-by still looked hopefully at the musicians who remained.

A young man stuck his head out the last window of a stopped Metrobus. "Ain't nobody gonna give you no quarter if you ain't playin' nothin'!" he advised. "Gotta play to win!"

He wanted to hear Beethoven, but trumpet player Dines replied that the group's 25-piece repertoire didn't include any. The man demanded, "Play anything!" but finally accepted the explanation that there weren't enough members of the quintet there to play.

The bus roared off. Dines and Loman shook their heads and laughed, then talked about getting some Beethoven pieces transcribed.

Expanding the repertoire was a frequent subject at Brass Inc.'s rehearsals, which took place at band members' homes or Howard University.

At a rehearsal at the university's Fine Arts Building, the sound bounced off the white cinderblocks of a tiny practice room. Students, drawn by the loud music, kept popping their heads in the door out of curiosity, knocking over Loman, the french horn player, who was perched precariously in the corner.

The rehearsal mixed talk of timing and tone quality with considerable good-natured ribbing and jokes. Powell ran the rehearsal and Dines set the tempo for each piece, but here, as in performance, the process was democratic. The other members were quick to reject "lip-killer" selections when they felt the strain of several hours' practice.

Though ice, petroleum jelly and rest can help, the quintet members know that years of playing can produce a "potato chip" upper lip, rippled like Louie Armstrong's.

"Even had a groove in the bottom of his lip where the air flows," Powell noted.

"Well, if you play as long as he did . . . since a teen-ager . . .," Dines replied.

"Look at your lip, your lip's gonna get like that."

"I know."

Musicians since childhood, the five first played together in the D.C. Youth Orchestra, in which Poindexter still plays the trumpet.

The quintet temporarily broke up this fall when Dines left for his first year at Ohio State. With another trumpeter filling in for Dines, the group has resumed playing in Georgetown and expects to continue until the weather turns cold.

Although they play a variety of music, baroque is the group's specialty. "Most literature written for brass quintet is baroque," Loman explained. But more important is the sound: "It's so easy to understand, it's just a melody," Dines said. "Nice, soothing music," Powell agreed. And playing in quintet, with five equal parts, builds endurance and "shows up your own personal virtuosity," said Loman.

Playing on the Georgetown sidewalk means competing with car horns, radios, crowd noise and other nearby attractions. Sometimes they are rained upon, and occasionally, when the sidewalk gets too full, moved by the police to a dark parking lot across the street.

But the quintet said the applause and the feedback make it worthwhile. "We have to know when we sound good," Dines said.

As Powell put it: "I used to be really scared to play in front of people. Now, after playing in Georgetown, I can play anything in front of anybody."