Turntables, vinyl records, boom boxes and microphones are being sought by the National Museum of American History for an exhibition on hip-hop culture.
Grandmaster Flash has donated a mixer and a hat
The project will assemble objects that trace hip-hop's origins in the Bronx in the 1970s to its current global reach.
It is expected to cost $2m (£1.1m) and take up to five years to complete.
"Hip-hop is part of American culture, just like jazz," said a spokeswoman for the museum, part of the Smithsonian Institute in Washington DC.
Personal effects - ranging from photographs, posters, handwritten lyrics, clothing and costumes - are being sought from hip-hop's early artists.
Grandmaster Flash, Afrika Bambaataa, Ice T and Fab 5 Freddy are among the hip-hop icons who have already donated exhibits.
At a ceremony in New York on Tuesday, impresario Russell Simmons called the Smithsonian's recognition "a great statement".
Russell Simmons is the founder of Def Jam Records
"It's not a signal to the end of hip-hop," said the co-founder of the Def Jam label. "We know it will be a lasting fixture.
"All over the world hip-hop is an expression of young people's struggles, their frustrations and opinions."
The Smithsonian initiative - entitled Hip-Hop Won't Stop: The Beat, the Rhymes, the Life - follows a similar exhibition - Hip-Hop Nation: Roots, Rhymes and Rage - held at the Brooklyn Museum of Art in 2000.
A spokesman said it planned to feature an exhibition on graffiti art later this year.