Theater types should be grieving as openly as rock fans are at the death of Lou Reed.

Reed was part of the Warhol Factory scene which formalized and popularized “happenings” and performance art in the 1960s.

His biggest hit, “Walk on the Wild Side,” was inspired by an assignment from Joe Papp’s Public Theater to create a musical based on the Nelson Algren novel of the same name. (Reed discusses this at length on his loquacious Live Take No Prisoners album.)

Two of his last three albums were originally staged as theater pieces:

• The Raven, based on the works of Edgar Allen Poe, was first presented in Berlin and New York (at BAM) under the title POEtry, a couple of years before the album (with an all-star cast of actors reciting Poe’s works) came out.

• The album Lulu, made with the metal band Metallica, is based on songs Reed composed for a German production of Frank Wedekind’s famous play, directed by Robert Wilson and performed by the Berliner Ensemble at Theater am Schiffbauerdamm in April of 2011. As with The Raven, it was two years after the stage presentation that a related album was finally released.

Reed inspired countless theater productions. I have great memories of a Yale Summer Cabaret rendition of Brecht’s Baal directed by Tea Alagic in 2005, with Reed represented as the title character and the Warhol scene the demimonde he inhabited.

Reed was also an obvious (and acknowledged) influence on one of the most important musical theater pieces of the last 20 years, Hedwig & the Angry Inch. That show’s getting a Broadway revival next spring starring Neil Patrick Harris.

He also, of course, was with Laurie Anderson, who did as much to expose a mainstream pop audience to performance art and experimental theater techniques as anyone since, well, the Velvet Underground. Reed and Anderson married in 2008 after having been together for a decade. They performed together occasionally, including at the Manchester International Festival in England in 2009.

But when I think of Lou Reed at his most theatrical, it’s Berlin hands down. One of the greatest rock concept albums of all time, its highly defined characters and dark dramatics have sadly never been fully explored in other media. The closest Berlin has come to a proper fleshing-out is the live concert version done at St. Ann’s Warehouse, filmed by Julian Schnabel and released on DVD in 2008.

Listen to Berlin. Give The Raven another chance. Don’t listen to what the pop critics and the Metallica fans said about Lulu. Lou Reed has a theater fan base that gets him in ways that his other fan bases don’t. Join it.