"When You're In" is a track from Pink Floyd's 1972

1972 in music

-Events:*January 17 – Highway 51 South in Memphis, Tennessee is renamed "Elvis Presley Boulevard"*January 20 – The début of Pink Floyd's Dark Side of the Moon at The Dome, Brighton, is halted by technical difficulties,...

 album Obscured by Clouds

Obscured by Clouds

-Singles:*"Free Four"/"Stay" *"Free Four"/"The Gold It's in the..." -Personnel:Pink Floyd*David Gilmour – guitars, vocals, pedal steel guitar, VCS3*Nick Mason – drums, percussion...

. It is entirely instrumental

Instrumental

An instrumental is a musical composition or recording without lyrics or singing, although it might include some non-articulate vocal input; the music is primarily or exclusively produced by musical instruments....

, with a repetitive guitar riff repeating until the piece fades out.

This song, along with "Obscured by Clouds", was played live in late 1972 and usually opened shows on the 1973 The Dark Side of the Moon

The Dark Side of the Moon

The Dark Side of the Moon is the eighth studio album by English progressive rock band Pink Floyd, released in March 1973. It built on ideas explored in the band's earlier recordings and live shows, but lacks the extended instrumental excursions that characterised their work following the departure...

tour. The live performances were often an extended version which allowed David Gilmour to perform a guitar solo and Richard Wright

Richard Wright (musician)

Richard William Wright was an English pianist, keyboardist and songwriter, best known for his career with Pink Floyd. Wright's richly textured keyboard layers were a vital ingredient and a distinctive characteristic of Pink Floyd's sound...

 to add a Hammond organ

Hammond organ

The Hammond organ is an electric organ invented by Laurens Hammond in 1934 and manufactured by the Hammond Organ Company. While the Hammond organ was originally sold to churches as a lower-cost alternative to the wind-driven pipe organ, in the 1960s and 1970s it became a standard keyboard...

 and Minimoog

Minimoog

The Minimoog is a monophonic analog synthesizer, invented by Bill Hemsath and Robert Moog. It was released in 1970 by R.A. Moog Inc. , and production was stopped in 1981. It was re-designed by Robert Moog in 2002 and released as Minimoog Voyager.The Minimoog was designed in response to the use of...

solo.