The scene: Washington Sangerbund hall above the Old Europe Restaurant on Wisconsin Avenue. Enter Bill Caldwell, a portly yet elfin man who is the first American-born president of the 131-year-old singing and social group. He is wielding a mop; as the others sing of melting snow, spring blooms and melancholy journeys, Caldwell swishes up some spilled beer.

At the Friday night rehearsals of the Sangerbund, beer and Brahms mix freely. Most of the drinking and socializing takes place in the bar before and after, but carrying steins and even pretzels into the rehearsal hall is not verboten. The group is rehearsing for its spring concert Saturday in Upper Marlboro, and musical director Michael Jahn is encouraged.

"The sound is already pretty good," said the blond, bearded young man, who also teaches at the German School in Potomac. Jahn frequently lapses into German, which all of the five dozen singers, who range from teenagers to graybeards but are mainly middle-aged, seem to understand.

"Achtung: eins, zwei, drei, und . . ." he commands, putting sopranos, altos, tenors and basses through their paces with folk songs, operetta music and songs by Mozart and Mendelsohn. The entire group sings some of the selections, while others are for one sex only. The men's chorus is doing Schumann's "Wanderlied."

"The atmosphere changes now," says Jahn, striking a different mood with a piano chord. "He is now in a different country . . ."

After some hours of rehearsal -- which some singers break up by going to the bar for a beer to bring back -- there are announcements about the concert; about an upcoming trip to Hershey, Pennsylvania for a songfest with other sangerbunds; about a member in the hospital; and about a birthday, which brings on German and English renditions of the Happy Birthday song.

Then, quickly, the rehearsal hall empties and the action shifts to the room next door, which has a bar, a lot of long tables, sangerbund flags and the trophies, trays and steins the group has won. There are many more people in the bar than were in the hall.

"We have both singing and non-singing members," explains Frank Pierce, a singing member who recently completed a history of the group, founded in 1851 by members of the Washington German community centered around Concordia Lutheran Church.

It included such prominent members of the local German community as brewer Christian Heurich and was inactive only during the anti-German eras during the world wars. "To become a non-singing member all you have to do is apply, and after your name is posted the board votes," Pierce said. "To become a singing member you have to be auditioned by the director and attend four rehearsals. Our goal is to preserve German folk music, which covers a wide range. Mozart wrote folk music, and Schubert. Singing is part of the tradition of being German. They take walks out in the country and sing."

"We like to sing, even in school we sing," says Richard Bennertz, who joined soon after he came here from Germany to do woodwork for the Army. Bennertz met his wife at the old clubhouse at 314 C Street NW, torn down in 1931.

"We also like to come together and drink beer," adds Max Karl Hille, a retired baker who is sitting with Bennertz and others and eating salami on rye and speaking German. "If you take the beer away you only have half the people here."

"I am the oldest singer here," claims Alfred Kopf, 80, who was president of the society during the difficult World War II years. "If I don't sing anymore I'm dead."

"I was brought up musical -- my father was first horn player in the Army Band -- and I'll sing anywhere," says Kate Murray, a writer and one of the few members who has had formal voice training. "It's great to meet a group like this, because they all sing anywhere. When I first came I didn't know any German. I sit next to Karin, and every time I make a mistake she elbows me."

Karin Halusa, a native of Cologne, lives in Woodbridge and makes a 50-mile round trip to rehearsals every Friday night.

"People think it's crazy, but this is a piece of home," she explains. "I have homesick quite a bit, especially in the holidays. I miss gemuetlichkeit. That's why I come."

The gemuetlichkeit is beginning in earnest, as Kate, Karen, Marita Buscher and husand Fritz start singing, locking arms and swaying in a fashion Germans call "schunkeln."

"In Munchen Steht ein Hofbrau Haus . . ." goes the song, in which others join, keeping time with their steins. Meanwhile, Caldwell announces that there is indeed something to rejoice about: a doctor visiting from Alabama has somehow found his way into the clubhouse and, citing some German ancestors, has donated a $100 bill to the treasury.

There are cheers of appreciation; Kate rushes to the bar and gives him a big kiss.

"Frei bier!" someone shouts, and the singing and gemuetlichkeit resume. GETTING IN TUNE -- The Washington Sangerbund's Spring Concert is at 8 p.m. Saturday at Mellwood Hall in Upper Marlboro. It will be followed by dancing to Sexton's German Band, and beer, wine and food will be available. Tickets are $5 per person. For reservations, call Mr. or Mrs. Joseph Eagler at 588-2814.

For information on joining the Sangerbund, call Bill or Inge Caldwell at 258-9355.

For copies of the history, which includes a lot of interesting Washingtoniana, send a check for $20 to Nancy Pierce, 206 Franklin Avenue, Silver Spring, Maryland 20901.