NOT MANY ROOMS are haunted by music, but the notes of a polonaise seem to echo endlessly around the ballroom of the Polish Embassy.

No one dances today at the Polish Embassy. Poland is in the midst of a crisis, a major turning point in the brave, centuries-old history of the Polish fight for independence. The ambassador, his staff and their family listen to the news, not polonaises.

But the great 16th Street palace, which has housed the Polish Embassy since 1919, has stood amid adversities before -- and emerged, like the nation, with its flag flying and its beauties and virtures unsullied.

The Soviet Union and the People's Republic of Poland, both on 16th Street, have been in their historic buildings longer than any other embassies. Of all the great houses on Meridian Hill, with their ballrooms or memories of ballrooms, the Polish Embassy is probably the least changed. Poland has never had money to throw away on things such as fluorescent lights, central air conditioning, asphalt tile, fiber board partitions and acoustical ceilings.

The mansion was one of a dozen or so designed by Beaux-Arts architect George Oakley Totten for Mary Henderson and Sen. John Henderson in their grand plan to make Meridan Hill and indeed all of 16th Street into the Embassy Row, if not the Avenue of the Presidents. The mansion was sold by the Hendersons to Prince Casmir Lubomirski in 1919.

According to Polish Ambassador Romuald Spasowski, "Lubomirski was a Polish citizen living in Washington. When Poland became an independent state. He was asked to become our minister. At that time, the United States did not exchange ambassadors, only ministers."

In 1972, the Polish Embassy bought a big plot of land on Tilden Street, near the new Czechoslovakian and Hungarian embassies, planning to build a new chancery.

The project came to the desk of Spasowski, then Polish deputy foreign minister. Spasowski, a man of taste and discernment who had earlier served as ambassador here, and lived upstairs at the old 16th Street embassy, wrote on the proposal a large "NO, never, over my dead body. I said the old house looks like an embassy should. It is a historic house, very fine. And it would cost millions to build a new one."

When he and his wife Wanda came to Washington for his second tour as ambassador in March 1978, before the current difficulties, they undertook a meticulous restoration of the handsome 1909 building, using all Polish craftsmen. They also purchased and remodeled a much needed ambassador's residence in Forest Hills.

The other day, the Spasowskis showed us both.

"We brought 12 Polish workers over," said Mrs. Spasowski, "otherwise, we couldn't have afforded it. I was the contractor. Since the workmen knew no English, and I knew no carpenter's terms, I had to sit at the phone or go to the lumber yard with a dictionary. I had never built anything before, but I learned."

At the chancery, the Polish workmen, experienced on the antique ornamentation of Polish palaces, did an remarkably fine job of restoring the mansion's elaborate plaster and woodwork. The staff of the Fine Arts Commission was in recently to measure the building for the forthcoming volume two of the 16th Street architectural history. "It's wonderful, you check today's pictures against the original photographs of the building and it's all exactly the same," said a commission architect, Richard Ryan.

Visitors come up the great stairs and their elaborate ironwork, past a series of offices, probably the original billiard room and library.

On the piano nobile, the second but principal floor, an intimate parlor (if a room 21 by 18 feet can be called intimate) now serves as the ambassador's office. He once was housed in a rather dark and gloomy room on the first floor, but Mrs. Spasowski suggested he use the pleasanter chamber. The room has two fireplace mantels, but only one fireplace. The other houses the heating vent. The ambassador proudly showed the portrait of Thomas Jefferson, "by his friend, the American and Polish hero General Tadeusz Kosciuszko."

In this charming room, filled with elaborate plasterwork and handsome Polish rugs, Ambassador Spasowski manages the delicate liaison between the Polish foreign office and the U.S. State Department. Spasowski is generally credited with helping to keep United States-Polish relations well balanced during the perilous times.

The Spasowskis try to keep their good humor but concern about their country and their people shows in the tight lines around their eyes and their grave faces.

At home, Mrs. Spasowski packs gifts of food and medicine for friends and relatives in Poland. During an earlier visit home, Mrs. Spasowski said, "I gave a friend a box of aspirin, and he would only take six. 'It wouldn't be fair for me to take a whole box myself,' he said. Recently, when a close relative died, the Spasowskis chose to send food packages home with the money it would have cost them to go to the funeral in Poland. At night, when the news comes on, the Spasowskis frequently listen to two stations, trying not to miss anything.

At the chancery, there is now only one cleaning person. Mrs. Spasowski polishes the collection of Polish silver. At the residency, Mrs. Spasowski gets up at 6:30 a.m. to do all the housekeeping, including the cooking for representational meals. "They have reduced what we get to run the embassy but with things the way they are now at home, we can't complain," she said.

But in the drawing room, white with pale blue accents and blue cutaway velvet upholstery, everything is immaculate.

In the drawing room, a painting of Ignace Paderewski hangs in a flowery Art Nouveau frame, over a Steinway piano he used on an American tour.

"He was a great Polish pianist, philosopher and statesman," said the ambassador. Many people still remember the recording of the "Polonaise Militaire" by Paderewski, played incessantly at the time of the brave fight against the Nazi takeover of Poland in 1939. The portrait and the piano dominate the great room with its elaborate neo-classical plaster pilasters and cornices. The tall French windows overlook 16th Street.

On the walls hang handsome paintings on loan from the National Gallery of Art in Warsaw. The royal jester and philosopher was painted by Jan Matejko in 1862. "And here," said Mrs. Spasowski, "is General Tadeusz Kosciuszko painted by Helen Modzejewska."

The gilded French furniture has been here perhaps from 1919. Other elaborate furniture, mostly Empire style, comes from the warehouses in Warsaw, where the government keeps fancy furniture, much of it French, from old Polish palaces, many of them now office buildings.

The ambassador's office and the winter garden, a sunny room with a south wall of glass and a mirrored fountain, lie between the drawing room and the ballroom.

The ballroom of the Polish Embassy looks like the sort of room that would call forth walzes and polonaises, though it is used more often today for meetings and conferences. The great coved ceiling is more than 12 feet high. The room itself is about 39 by 21 feet. Between elaborately scrolled pilasters of the composite order, combining elements of Ionic and Corinthian, a bank of French doors fill the room with south light. The fireplace with its white columns and generous firebox promises warm winter evenings. A great red rug stretches the length of the room. The ballroom was not built when the main part of the house was completed, but added a few years later before the house was sold to the prince.

The dining room, about 39 by 20 feet, seats 20. It too has fanciful ornamentation, tall windows and an ornate fireplace. A few pieces of Polish silver sit in the glass cabinets. The walls are covered with elaborate oak work, painted years ago, and now in a white and ice blue combination. The dining room chairs here, and a few others sprinkled through the embassy, come from the Spanish wife of a previous ambassador.

The ambassador and Mrs. Spasowski on their last tour here lived on the upper floors of the embassy with their son and daughter, then small children. "It was not easy to keep them quiet and out of the way," Mrs. Spasowski remembers. But now with 30 diplomats at the embassy, the space was needed for offices, though some staff is still housed on an upper floor.

Mrs. Spasowski had the job of finding a suitable residence. She thinks she was fortunate to find a house on a pleasant and imposing setting, on a hillside in the Forest Hills section, where are housed a number of embassies, including the Italians who bought Firenze House and its 30 acres, as well as the Czechs and Hungarians who built extensive new chanceries and residencies.

The Poles paid $482,500 for the stone house on the top of the hill which included more than an acre of land. They spent another $35,000 remodeling, not counting the volunteer work of Ambassador Spasowski as architect and Mrs. Spasowski as contractor.

He showed the plans he drew, with overleafs.

"We added an apartment on the lower floor," Mrs. Spasowski said. "We thought originally for two servants. The driver lives there now." The top of the addition serves as a terrace, with a new door off the living room. "And we extended the sunroom, as well as making repairs and such."

You come up to the house on a drive that goes pass a large lily pond. "I'd like to keep goldfish to clean it," said Mrs. Spasowski, "but I'm afraid the raccoons will eat them."

Inside, a large drawing room is on the left, with antique Polish furniture and paintings of Polish scenes by Witold Kalicki, a Pole now living in Alexandria. A very fine secretary with ormolu painted by Paul Sormani of Paris stands in the room.

The dining room on the right of the hall has three large glass front cabinets in the Biedermeyer manner, one is original, the others copies. A long library is beyond the dining room, here with traditional furniture currently being reproduced in Poland. The tambour desk, though, is an antique.

Across the back of the house is a long sunroom.

Mrs. Spasowski sat with us here the other afternoon, over lunch she had cooked. She talked about other troubled times in Poland. "I was only 12 when the Nazis invaded Poland," she said. "But all of us worked for the Underground. I used to carry anti-Nazi pamphlets from the printing presses to the distribution points. Once I was stopped, and the Nazi officer examined my shopping bag and my pockets, but I had the pamphlets in my muff, and he didn't think to look there."

Spasowski, whose is seven years older, was immediately suspect because of the reputation of his father, a university professor. He had to go underground. Even so, the two were married when she was 17. "My father said, you know it will be more difficult for your husband because you are married, but we thought we might have only a little time and we wanted to be together, so after the Warsaw uprising we were married. Our first child was born two years later."

Surviving the war, Spasowski joined the Polish army and was sent in the military liason to Germany. Then he was named a consul in Du sseldorf. He has also served as ambassador to Argentina and in offices in Saigon and India.