WATCH: Lou Reed: Perhaps Bisexual, Definitely a Voice for All

While some commentators are describing Lou Reed, the legendary singer-songwriter who died Sunday, as the first openly bisexual rock star, Reed was often evasive about his sexual orientation -- but he was also a voice of acceptance for all.

The Velvet Underground, the band with which Reed first gained fame, cultivated an androgynous image, and Reed wrote and sang about gay and transgender friends as well as his own experience with "ex-gay" therapy -- he underwent electroshock treatment as a teenager to curb "homosexual tendencies," an experience he described scathingly in his 1974 song "Kill Your Sons."

He sometimes told interviewers, however, that the androgynous image was just that, an image, which led acerbic music critic Lester Bangs to write in 1973 that Reed may be "rock's ultimate closet queen by virtue of the fact that he came out of the closet and then went back in," or perhaps "a heterosexual onlooker exploiting gay culture for his own ends." He was married three times to women; his last marriage, to performance artist Laurie Anderson, who survives him, was by all accounts a happy one.

Reed's songs, though, were often odes to diversity and acceptance. His biggest commercial hit, 1972's "Walk on the Wild Side," was about the gender-bending and sexually multifarious entourage that surrounded Andy Warhol, including transgender performers Holly Woodlawn and Candy Darling, and gay-for-pay actor Joe Dallesandro. He also wrote about Darling in "Candy Says," which has the lyric "Candy says I've come to hate my body." He eulogized friends lost to AIDS in "Halloween Parade" and denounced right-wing intolerance in "Sex With Your Parents."

Reed "wrote about all kinds of topics that were taboo before he started exploring them," including the lives of gay and transgender people, Rolling Stone senior editor Simon Vozick-Levinson told CNN.Slate contributor Mark Joseph Stern, noting rumors about Reed's male lovers and the artist's own cryptic comments about his orientation, concluded that "the precise parameters of his sexuality ... remain unclear. Whether Reed was bi, pan, or ambisexual, we only know for sure that he was, to the end, a thoroughly modern man."

Watch video below of "Walk on the Wild Side" and "Kill Your Sons."