The President's House hadn't been completed and the nation's new capital was barely more than a swamp when John and Abigail Adams held their New Year's party in 1801. Musicians in bright red coats provided the afternoon's entertainment in a building in which the first and second floors were connected by ladders and a clothesline held the first family's laundry in the East Room.

The Adams party is recorded as the first public reception at what would later be called the White House. Less commonly known is the reception's other first: the White House debut of the U.S. Marine Band.

It is the oldest continuously active unit in the Marines and the oldest musical group in the United States. The band rode with Abraham Lincoln to Gettysburg and has played at every inauguration since Thomas Jefferson's in 1801. It performed at the opening of the National World War II Memorial, the Statue of Liberty, the Washington Monument and the White House.

Though it was signed into existence by John Adams in 1798, the band was christened "The President's Own" by Jefferson, Adams's political rival, after his own inauguration.

A deep sense of this history underlies the band's affairs, permeating ceremonies that mark changes in directors, the addition of members and an impending move to new barracks.

Earlier this month, Col. Timothy W. Foley, 57, of Arlington, the band's director, passed a gold engraved baton to Lt. Col. Michael J. Colburn, 39, of Burke, who became the band's 27th director. The two conductors wore traditional black with gold cords, nearly identical to the uniforms directors wore a century ago, and the baton was the same one presented to their most famous predecessor, march composer John Philip Sousa. Also, 1st Lt. Michelle A. Rakers, 35, of Woodbridge was set last night to become the first woman to conduct the band as assistant director.

This fall the band will move from the Marine Barracks at Eighth and I streets SE -- the "oldest post of the Corps" -- to new quarters at Seventh and K streets SE. It will be the band's first move since 1801. The new barracks will have more practice rooms and rehearsal space, and new administrative offices.

Also, in October the band will add 11 positions, including clarinet, trumpet, French horn, trombone and tuba players, a percussionist, an assistant stage manager and a library staff member, said the chief librarian, Master Gunnery Sgt. Mike Ressler, 52, of Burke.

These are big changes for an organization of steadfast traditions and precision, steeped in history.

The band's official mission is to provide music for the president and the commandant of the Marine Corps, but its responsibilities now include weekly concerts at the U.S. Capitol, frequent concerts in Northern Virginia, Marine Barracks parades during the summer and a national tour each fall. This year the band will spend seven weeks on the West Coast, playing a different city every night. The band's various ensembles average 800 performances a year.

By providing a backdrop for historic moments, Foley said, the band contributes to the ambiance of the White House for state visitors, honored guests and the first family. Colburn said the band's performances sometimes are background music, but not always.

"You never know when somebody's actually listening with great attention to detail," he said.

Colburn learned that lesson a few years back while he was conducting the English Folk Song Suite at the White House and felt a tug on his elbow. Expecting to see an usher, Colburn turned around. It was President Clinton.

"Clinton said, 'This is one of my absolute favorite pieces; I'm so glad you're playing it,' " Colburn said. Then the president discussed the piece in detail, naming the movements and recalling particular elements.

"He couldn't have played that since high school," Colburn said.

Just as the White House staff, decor and image change with each administration, the musical taste of each president must be discerned by the band leaders, Ressler said.

Although Clinton knew band music better than other recent presidents and once sat in on saxophone while he was governor of Arkansas, Ressler said Jimmy Carter may be the "most musically astute" of modern presidents, often standing near the orchestra to listen.

Ronald Reagan particularly liked country and western music, Ressler said. On one of the last nights of his administration, Col. John R. Bourgeois, the band director at the time, gave him a special-model harmonica.

Standing before the orchestra in the Grand Foyer, Reagan blew a couple of notes. Then, after waiting just long enough to give orchestra members the notion that he had finished, Reagan began a rendition of "Red River Valley," to the orchestra's applause, Ressler said.

Jefferson may have taken the most active role in the band's evolution. During his administration, the band played Saturday afternoon concerts in the summer and fall, often on the White House lawn. Unimpressed by the band, Jefferson, himself a trained violinist, sought to enlist musicians from Italy. By 1805, 18 had arrived, but because of bureaucratic problems with the military, only a few stayed long enough to join the band.

Even musicians who are used to playing at the White House can be impressed by brushes with presidents. Master Sgt. Janice Snedecor, 43, of Crofton, a clarinetist, had been in the band for 11 years when she played in a chamber ensemble celebrating the 200th anniversary of the White House, in November 2000.

Toward the end of the evening, as the ensemble played in the Grand Foyer, Snedecor said, the four presidents in attendance -- Carter, Gerald R. Ford, George H.W. Bush and Clinton -- began dancing with their wives.

"They were right next to us, dancing," she said. "All four of them together like that was something you don't see often."

With performances at a variety of events including bill signings, state dinners, ticker-tape parades and memorial services, the band's musical selection remains a careful process.

For state dinners, Foley said he tried to select music from a leader's country. That is most difficult for Asian leaders, he said, because most Asian music is performed in different modes and scales than traditional Western classical music. Nonetheless, he said proudly, for a visit from the South Korean president he managed to find Korean folk music that could be arranged for the band.

Show tunes, music by George Gershwin and Richard Rodgers, and songs from current movies are favorites, Foley said.

Colburn likens the music selection process, in which he participated as assistant director, to designing a menu for dinner guests. The pieces must fit together, he said, but there must be variety, too.

While practicing, the musicians resemble any concert band, sitting two to a music stand with bottles of diet cola and water at their feet. They dress casually, though to adhere to the Marine code the men tuck in their shirts and sport the required fade haircuts.

Publicly, band members wear red coats with gold cords as they serenade presidents and state guests at the White House or accompany funeral rites at Arlington National Cemetery.

For some members, being part of the band is the realization of childhood dreams formed after hearing performances in Reno, Nev., or Interlochen, Mich. For others, "The President's Own" was simply another audition in the job search that somehow landed them on White House balconies and marching in military parades.

Nationally advertised through music journals and top music schools, auditions often draw 50 to 100 people, Ressler said. The winner of an audition is enlisted for duty with the Marine Band on a contract that prevents the musician from being transferred to another unit. Band members do not participate in basic training, because they're already highly trained in music, Ressler said.

Because most who enlist join for the music rather than the military service, it often takes time for them to fully understand the organization's history, Colburn said. But the traditions -- which include beginning every concert with "The Star-Spangled Banner" and ending with "The Marines' Hymn" -- slowly become as important as the music. Nearly all the band's members stay until retirement.

"Gosh, in this organization, it's hard to find something that isn't traditional," Colburn said.

And then there's Sousa.

The internationally famous director led the band from 1880 to 1892. The son of a military trombone player, Sousa joined the band as an apprentice musician at 13 and became a playing member four years later. Though he left after three years, he returned to direct the band. During his tenure, Sousa began writing the marches for which he is known, including "The Gladiator," "The Washington Post March" and "Semper Fidelis," which is dedicated to the Corps. He wanted to rejoin the Marines when World War I started, but his request was rejected. Instead, he joined the Navy and trained its musicians.

If there's any question about the place Sousa has in the band's memory, a visit to the director's office settles any doubts. Sousa is immortalized in four photographs and paintings, including one of him in a Navy uniform, and perhaps in a fifth -- there is speculation that, in the front row of a Civil War-era photograph of the band, a young Sousa is hiding between two trombone players.

The baton that Foley passed to Colburn was given to Sousa in 1892 and bears his name in gold engraving. Sousa's Tiffany lamp, with a blue and green stained-glass shade decorated with outlines of fireflies, stands in a corner of the director's office. Across the room, a cabinet holds medals Sousa won for skeet shooting and other outdoor activities. The new band barracks may be named John Philip Sousa Hall.

Another Sousa portrait overlooks the room where band members often practice, an ever-present reminder of the tradition to which band members belong.

For some, it's not easy to forget. Staff Sgt. Michelle Urzynicok, 32, of Bel Air, Md., knew she wanted to join the band since she heard it at the Interlochen Arts Academy in Michigan, where she attended high school.

She was studying in Germany in the late 1990s after earning a master's degree when she heard there was an audition for the band, and she flew to Washington to try out. She got the spot and joined in 2000.

As an E-flat clarinetist, Urzynicok often played "Hail to the Chief" on the White House balcony during the Clinton administration's tenure. She made her father proud this summer when she marched in the Reagan funeral procession, she said. She loves the music the band plays, loves being a part of history and is proud to perform with top-caliber colleagues.

"Sometimes I still can't believe that I play here," she said.

From left, Gen. William L. "Spider" Nyland and Lt. Col. Michael J. Colburn thank Col. Timothy W. Foley, the U.S. Marine Band's 26th director, for his years of service at a July 17 concert in Alexandria. Foley recently passed the baton to Colburn.