It was an intriguing dream: Create a museum of popular music in downtown Seattle that would celebrate the musicians who have defined the genre for the past 50 years.

The curators scoured archives and collections for artifacts that would help trace rock-and-roll from its infancy to today's sound. They brought together the familiar recordings as well as tapes of forgotten sessions. They gathered the tangible trappings: the stage costumes, the posters, the instruments, the tickets. They documented the contributions of Hank Williams, Willie Mae "Big Mama" Thornton, Chuck Berry, Elvis Presley, Bob Dylan and bands like the city's Nirvana and Soundgarden and early rappers Sugarhill Gang and Grandmaster Flash.

The man driving the dream is Paul Allen, co-founder of Microsoft and someone whose money can match his vision, which he calls the Experience Music Project. His touchstone has been Seattle's great Jimi Hendrix, an icon of the hard-rock era and a man who inspired a generation of musicians to break rules and take risks.

Allen wanted that same kind of sweet inspiration captured in some way by the museum itself.

That, everyone knew, would be harder. How does a museum trace the way a group of guys singing on a corner in New York got a record contract and a Top 40 hit? Or how a club owner in Minneapolis in the 1980s heard the Replacements and decided punk was the future of rock? What oral histories would help tell that story? How did "sampling" develop? And Allen wanted more: studios so visitors could attempt to make music themselves.

He recruited architect Frank Gehry, an understated 70-year-old who could hardly be mistaken for the king of rock-and-roll. But the architect--who has also been chosen to design an addition to the Corcoran Gallery in Washington--has a reputation for taking challenges and making them into one-of-a-kind conversation pieces. He was, Allen decided, the man to design a building to embody these ephemeral strains.

Gehry confronted the question of what such a music museum should look like. Should it have a confining shape--a triangle, perhaps--so small and so tight, representing the moment the songwriter plays with words and makes a ballad? Or should it be an old-fashioned box, open yet predictable like the thousands of arenas the bands pass through? Or a series of rooms with low ceilings where one could feel blues, jazz and folk music suspended in the air?

Or should a music museum take its cues from the sports arenas, where people are packed under a dome and showered with special effects and gigantic video screens? Or perhaps the shape is a ring--like records, like CDs, like the music that seems to be constantly circling back around.

After six years of planning, the collaboration between Gehry and Allen, who is bankrolling the project with $100 million of his own money, is taking shape at Seattle Center, the city's sprawling entertainment district. Next to the landmark Space Needle, the Experience Music Project is something like a disc, albeit a wobbly one--a vinyl 45 left out in the sun. Right now, some of its curved ribs are showing and the outside is a series of vaulted buttresses. Eventually all will be covered by broad colored sheets of stainless steel and aluminum. This is way past Gothic arches. The outside panels have been dipped and dyed in purple, gold, blue, silver and red. One of the connecting pavilions has even been built over the city's landmark Monorail train, which now zips through a corner of the structure.

No one knows quite how to describe the building. "It's electric, magnetic," says Paul Zumwalt, the project's design and construction manager, as he stands amid cranes and mounds of dirt at the site. Some of the exterior walls are in place, and the colors can be seen some distance away. The galleries, auditoriums and shops will eventually encompass some 140,000 square feet.

That gives the designers enough space to display 3,000 of its 80,000 artifacts at a time; among EMP's huge collection are guitars used by Hendrix, Dylan and Kurt Cobain. The cultural and musical innovations of rock are the core story of the museum, but there will be exhibits on blues, funk, hip-hop, wing, ska, country, world music, reggae and punk.

This site was the location of the 1962 World's Fair, the year the Space Needle debuted. Now the Needle looks down on a modest amusement area, a science museum and Gehry's uncompleted creation. From the observation deck, the museum looks like a genetically altered cauliflower.

Allen told his architect and designers that he wanted to let everyone groove a little, "rather than displaying static exhibits as most traditional museums do."

Gehry says he initially was a little baffled by the talk of paying homage not only to the individuals but also to the creative process. "Getting together on the ideas took a while," he says. Allen, who plays the guitar, kept talking about "making it swoopy," a catch phrase for something with a look of suspended curves.

"He is a left-brain guy--where the computer and the music live. My realm is the right one. Initially it was hard to connect to him," Gehry says. Hendrix was often the guidepost in their discussions, and Allen also gave Gehry a book of guitar history. "He talked a lot about Jimi Hendrix, the rock guitars and the rock period he grew up in. I watched that period but I didn't jump into it," Gehry says.

But he was game to have a handsome budget at his disposal as well as a chance to work with a younger visionary. Gehry constructed and deconstructed about 40 models for Allen.

"He also picked things in my office that were ideas prior to this. He kept saying 'swoopy.' And soon I thought it was endearing, sweet. I just loved him for saying it," Gehry says. Because of this, there are no straight surfaces.

This is Gehry's fourth museum: In Los Angeles, he did a temporary home for the Contemporary Museum; in Minneapolis, he did the Frederick R. Weisman Art Museum; and in Spain he designed the Guggenheim Bilbao, which has been called the most important building of the last quarter-century.

Gehry is trying some new things. The three-dimensional sketches for the EMP were done on a computer system developed by the French and picked up by Boeing for its 777 jetliner. Gehry used the same system, called CATIA, toward the end of the Bilbao design phase. "We did a building by computer for a computer guy," says Gehry. He has not visited the site since construction started but checks on its progress every day using the project's award-winning Web site (www.experience.org). Very quickly, Gehry can check the installation of the curved steel beams--600 ribs have been installed to date--and the attachment of the aluminum and stainless steel panels, 4,000 in all. He checks to see if the purple, gold and silver sheets that have been dipped in an electrically charged acid bath glow as they did in his mind's eye.

"We took it quite far," Gehry says. The museum is expected to open in May and draw 800,000 visitors a year. At Experience Music, Gehry has also designed the interiors of the lobby, cafe and store. "As we pushed the envelopes of the shape, they created the technology to create it. They kept telling me I could do it."

Rainbow Vision

The centerpiece is the Sky Church, an open area that curves on two sides. It takes its name from Hendrix's vision of the communal rainbow peacefully creating and performing. The space will contain a huge frieze with still and moving shots of great musicians and moments in music history, and there will be room for live concerts, too. This section is, as befits something inspired by the creator of "Purple Haze," under a purple cover. There is a gallery for Hendrix that will display the guitars from the first Woodstock and the Monterey International Pop Festival, and other artifacts.

Since Allen originally thought this would be a Hendrix memorial, there is a significant amount of rare Hendrix material in the exhibits. Last year the museum acquired 19 tapes of him--encompassing 50 live recordings--made at New York's Fillmore East in 1969 and 1970 during his Band of Gypsies era. There's an audio mixing board from his Electric Lady Studio and headbands and other apparel from appearances at Newport and other festivals. (The Hendrix heirs, who have their own multimedia commemoration to the entertainer, have no relationship with the Allen museum, says family spokeswoman Janie Hendrix.)

The Hendrix retrospective is part of the museum's Crossroads Gallery. Included in that area is a tribute to music created in the Pacific Northwest. Ray Charles made his first recording--a ditty called "Confession Blues"--in a Seattle studio in 1949. It will also range from Bing Crosby (a native of Tacoma) and Quincy Jones's younger years to the rockabilly acts of the 1950s to Seattle's part in the fight to get the Kingsmen royalties for their 1964 hit, "Louie Louie." There will also be recognition of bluesman Robert Cray, Pearl Jam, Nirvana and Alice in Chains.

Throughout the museum are rare artifacts: jazz and R&B posters from the 1930s and 1940s, Elvis Presley's black leather motorcycle jacket, a 1986 Chevrolet Beauville van used by Soundgarden. Guitars are a running theme throughout, with the collection including an acoustic guitar owned by country legend Hank Williams, and others that date from the 18th century.

At the heart of the live-music attractions is the Sound Lab, a spot where visitors can get a tutorial on drums or keyboards. Museum-goers can reserve a "pod" for a more private jam session, or climb up on a stage and perhaps get the sensation of standing in front of a screaming crowd. "It's part music, part hands-on science, part Disney," says project manager Zumwalt. Bring your own groupie.

There's an Electric Library, a media resource center where the visitor can kick back and learn more about people and musical styles. In all of this is a 200-seat theater for performances, films and master classes. The exhibition areas are covered with a metallic red and gold skin.

A particularly unusual feature--this one wrapped in blue--is Artists' Journey, a ridelike attraction that will strap visitors in and rock them through a film about the lives and music of various artists. The film is being designed by Digital Domain, the company that did special effects for "Titanic" and "Apollo 13." The ride component is being designed by The Floating Co., a San Francisco group that does the Rolling Stones' stage sets.

Hum a Few Bars

Music is one of the hardest art forms to capture in a museum, and so far there are few successful blueprints for the Experience Music Project.

Despite the inherent challenges tied to a sound experience, there are some prototypes.

The Country Music Hall of Fame, after years in downtown Nashville, is building a new, $40 million home that will open in 2001. The Rock and Roll Hall of Fame in Cleveland opened in 1995 and enjoyed a blockbuster start, but the flow of visitors has tapered off to about 600,000 a year.

Detroit's Motown Historical Museum and Gospel Music Hall of Fame are both modest operations. The Delta Blues Museum in Clarksdale, Miss., is considered a shrine. A group in New York is considering a museum dedicated to jazz. And plans are underway for a National Music Museum in downtown Washington, scheduled to open in 2003. That museum, being organized by the Smithsonian Institution, the Library of Congress and private interests, will have the arrangements, films, scrapbooks and clothing of Frank Sinatra at its core.

Jason Hunke, Experience Music's communications manager, thinks the Seattle museum will capture imaginations because it has at its center a simple idea.

"This is about music, creativity and education," he says. "You wouldn't put a museum like this is a square box."

UP NEXT FOR GEHRY: THE CORCORAN

The colorful, irregular exterior of Frank Gehry's Experience Music Project in Seattle might be reminiscent of the Temptations' coordinated suits, the flowered shirts of Jimi Hendrix, the prewashed jeans of Bruce Springsteen, the candy colors of Cher, the blondness of Stevie Nicks and the roughness of the times from the blues to grunge.

In Washington, where Gehry's next project is an addition to the Corcoran Gallery of Art on New York Avenue, his inspiration might be the whiteness of the surrounding buildings or the green of the Ellipse and the Mall or the country's flag. Gehry says he learns from each of his projects and takes that knowledge on to the next one. In Washington, the influence of the Seattle project will come from the research and innovation he did, not the specifics. "The pool of research will impact the Washington thing. This building is one of a kind."