No one likes to acknowledge that their heroes have become passe. Seeing vitality in the idols of one’s youth is a means of prolonging it – or denying that it’s ended anyway. But with the release of “Face the Truth,” the third post-Pavement album by Stephen Malkmus, the conclusion is unavoidable. While it holds certain nostalgic pleasures for children of 1990s indie rock (of which I am one), it also reinforces just how long ago the music mattered.

If, as is often said, everyone that bought a Velvet Underground record started a band, then everyone that bought a Pavement record started a zine.(For those too young to remember: It’s like a blog, only printed on paper.) The music epitomized what a colleague once called “collar-out music”: sarcastic, hyper-literate, arty indie rock.

Pavement was to the 1990s what R.E.M. was to the 1980s – the underground’s favorite son. Only, by the 1990s, to be “indie” was much more a conscious decision. At a time when greasy hair and macho flannel ruled the pop chart, Pavement – along with bands like Luna and Yo La Tengo – provided an intelligent alternative to alternative rock.

Singer-guitarist Stephen Malkmus was the perfect vehicle for this nerdchic. He had the floppy-haired, cross-country-runner looks that made the horned-rimmed-glasses girls swoon, and wrote stream-of-consciousness lyrics – smart, funny, and damaged – that made semiotics post-grad students react much the same way. Suddenly, the smartest kid in class could also be the coolest.

The music took the experimentalism of noise and lo-fi with the fury of hardcore, presenting the rackety result with a smirk. But, like R.E.M., there were always lovely melodies lurking just beneath the rough surfaces. Sometimes just above them. “Slanted and Enchanted,” Pavement’s breakthrough 1992 album, and 1994’s “Crooked Rain, Crooked Rain,” the height of their ragged craft, alternated pop gems like “Zurich Is Stained” and “Cut Your Hair” (a radio and MTV hit) with blasts of feedback and whipped-off shambles.

This sugar-then-rat-poison bait and switch played out, writ large, in the band’s career. They followed “Crooked Rain, Crooked Rain,” which seemed to set them up as Nirvana’s zeitgeist defining successors, with “Wowee Zowee,” a half-hearted album even by Pavement standards. It was, it seemed, their penance for the success of “Cut Your Hair.” Like the Replacements before them, Pavement had an instinct for self-sabotage.

But if they saw no future for themselves, they saw rock’s future as equally dubious. “Crooked Rain, Crooked Rain” ends with the elegiac “Fillmore Jive.” On it Malkmus maps the rock tribes: “The Jam kids on the Vespas / and glum looks on their faces / This street is full of punks / they got spikes / See the rockers with their long curly locks …” then bids them all farewell, “goodnight to the rock ‘n’ roll era / they don’t need you anymore …” It was a swan song for an era – a surprisingly prescient one. Part of the reason no one else saw it coming was that Pavement made the music seem so vital and full of possibility.

“Face the Truth,” Malkmus’s new album, belongs to the changed world he foresaw. The indie underground is no longer in dialogue with the pop charts, and this loss of tension robs Malkmus’s music of much of its potency. What we’re left with is an aggressive playfulness and an urge to amuse himself.

Reviews are calling the album “psych-folk,” but only for lack of a better term. The opening song, “Pencil Rot,” has a weirdness worthy of Beck’s “Midnight Vultures.” Over a bed of squibbing electronics and squelched, ThinLizzy-sounding guitars, Malkmus trades lines with a trio of Malkmusfalsetto backup singers. A little later, he delivers Beck-like pomo raps over muted electro beats: “I’m here to sing a song about privilege / the spikes you put on your feet / when you were crawling and dancing to the top of the human shit pile.”

Unlike Beck, however, Malkmus doesn’t have the patience to stick with a single style; “Face the Truth” is all over the map, “I’ve Hardly Been” has a vaguely bossa nova vibe. “Loud Cloud Crowd” begins very much like an attempt at a Simon and Garfunkel tune by someone who knows he can’t pull it off, then blossoms into dreamy orch-pop choruses. The minimalist funk of “Kindling for the Master” sounds like the beginnings of an LCD Soundsystem beat.

Malkmus has always tried to contain his inner Neil Young, and on the eight-minute “No More Shoes,” he lets it out to play, interrupting long guitar solos with dadaist lyrics like “spare me your contrarian thaw” and “I want my Alka-Seltzer.”

But the album’s best moment is its simplest, and not coincidentally, it’s most nostalgic. “Freeze the Saints” is a pretty, sun-kissed piano tune that recalls equally languid late-Pavement songs like “Spit on a Stranger” and “Major Leagues.” On it he implores the listener to “learn to sing along and languish here / help me languish here.” It’s an invitation they’ll gladly accept.

Stephen Malkmus plays Irving Plaza June 7 (17 Irving Place, at 15th Street, 212-777-6800).