On September 12 in 1975, Pink Floyd released its seventh album, “Wish You Were Here.” After already reaching worldwide fame for the milestone album, “Dark Side of the Moon,” this album became another classic in its own right within the band’s long list of work.

You may only know this album, or “Dark Side” for that matter, for their album covers that have spawned millions of T-shirts. But “Wish You Were Here” is still a significant piece of music from the iconic psychedelic rock band decades later, albeit for different reasons than some of Pink Floyd’s best-known works. Its title ballad is one of their most-played tracks, and yet the rest of the album is more difficult to turn into a radio single, being a tight, detailed composition and a true concept album.

The timelessness of this album, in my opinion, partly rises out of the pain and disillusionment with the music industry expressed by Roger Waters and woven throughout its structure. Partly a criticism of the music business and partly a tribute to ex-bandmate Syd Barrett, who suffered a mental breakdown, it is an older brother in many ways to the band’s later album and film, “The Wall.” “The Wall” dove deep into a portrait of the inner turmoil of a rock star hit by superstardom, tearing apart society’s pressures, rituals, and structures that can destroy the individuals within them. Before that album could come to be, “Wish You Were Here” looked back mournfully at a lost bandmate, a heartfelt examination of the loss of Syd Barrett on the band, particularly on Waters.

Listen to the album without stopping and its cohesion is unmistakable. In my opinion, the standout track here is truly “Shine On You Crazy Diamond”. Although less approachable than some of their other works – perhaps because it has no readily recognizable guitar riff, is over 12 minutes long, and is entirely instrumental until over 8 minutes in – this is one of the band’s masterpieces. Soaked in fond remembrance of Barrett, the song takes on a more existential symbolism in the psychedelic video which later accompanied it.

“Shine On” crosses into “Welcome To The Machine,” which opens with an opening door and ends with sounds of a party. “Have a Cigar” then scoffs and pokes fun at the cynical record industry. The acoustic “Wish You Were Here” then symbolizes both the loss of the ailing Barrett and the conflict in Waters between greed and ambition opposing his own idealism. It then closes with a reprise of “Shine On”.

Take time today to listen to “Wish You Were Here” even just to be transported back to a different time in the 1970s when the music industry was pumping out rock stars, and Pink Floyd felt like one of the few bands criticizing it. The album is an unforgettable journey into a band’s psyche and a timeless entry in the progressive rock genre.

Natalie Hanson can be reached at [email protected] or @NatalieH_Orion on Twitter.