LONDON (Reuters) - Pink Floyd, the British progressive rock group whose "Dark Side of the Moon" is one of the best selling records of all time, has announced its first new studio album in 20 years will be released on Nov 11.

"The Endless River" is a tribute to Rick Wright, the band's keyboardist who died in 2008, the band said on its website.

The album is primarily made up of music that Wright, guitarist David Gilmour and drummer Nick Mason put together during a session in 1993 that led to the last studio album, 1994's "The Division Bell".

"The band have spent the last year recording and upgrading the music, using the advantages of modern studio technology to create 'The Endless River'," the website said.

It is a primarily instrumental offering, with just one song.

"(Wright's) keyboards are at the heart of the Pink Floyd sound," the band said.

Pink Floyd is one of the most successful bands in rock history. According to Billboard, its 1973 "Dark Side" album is estimated to have sold more than 45 million copies worldwide.

The band's style - epitomized by other 1970s releases such as "Wish You Were Here" and "The Wall" - was cutting edge for its era, mixing soft and heavy rock with philosophical lyrics and pioneering electronic sounds.

The band also is known for its revolutionary light shows and ethereal album artwork.

"The Endless River" continues the latter tradition, featuring a standing man, back to the viewer, rowing an old boat across the clouds toward what is either a sunset or sunrise.

Gilmour and Mason are the two remaining members of the band still working under the Pink Floyd name. Original member Roger Waters left in the 1980s for a solo career.

With Wright, the four played together in a one-off reunion in July 2005 for the "Live 8" anti-poverty concert in London.

The fifth member, Syd Barrett, died in 2006. He left the group in 1968 suffering from what is widely believed to be drug-induced mental illness.

He is still considered by many to be the driving force behind all that Pink Floyd became, however.