At the start of 2009, Pearl Jam were without a record deal and seemingly without a meaningful future. As the only major survivor of Seattle grunge and 90s mainstream rock to resist implosion, the band, still based in Seattle after all these years, appeared anachronistic, past-it, irrelevant. Beginning with 1996’s “No Code,” and most noticeably with 2000’s “Binaural” and 2003’s “Riot Act,” Pearl Jam produced minor, experimental records, collections of songs in different genres rather than coherent albums. Worst of all, these albums visibly lacked ambition, an inexcusable failing in a band that had once sought to change the world. Increasingly, Pearl Jam were out of sync with the wider marketplace and with the zeitgeist of contemporary rock. As grunge died, they responded by moving into the past, absorbing the traditions of classic rock. The group’s eponymous album was an attempt, in part, to recreate their grunge roots; it was dominated by lean, brief, hard rock songs, but though it attracted some moderate critical approval it soon faded away, having failed to excite even the faithful.

With this background, it is almost ridiculous that in 2009—18 years after their debut, “Ten,” and with all five members well into their forties—Pearl Jam should release “Backspacer,” a propulsive, relaxed, enjoyable, and timely album. Few, if any, other bands could have released their finest work in such circumstances and at such a stage in their careers; “Backspacer” is a wonderful, genuine, rare surprise. How were Pearl Jam able to recapture lost magic and acquire magic they never had?

Part of the answer seems to be that Pearl Jam has never before been so at ease with themselves. On their early grunge albums, melodramatic tales of abuse and depression fit into a wider theme of anger at the vicissitudes of life. On “Riot Act” and “Pearl Jam,” their most overtly political albums, Eddie Vedder sounded like he had the weight of the world on his shoulders. “Backspacer,” by glorious contrast, features Vedder and the band deriving immense enjoyment from their craft. In every riff and solo, in Stone Gossard and Jeff Ament’s versatile rhythm section and Matt Cameron’s punchy drumming, their pleasure and relaxation can be felt.

But the biggest revelation is Vedder. For the first time, the lyrics are upbeat, not dwelling on the world’s woes so much as engaging with the hope of overcoming those difficulties. Of course, many bands sing and play optimistically, but few manage to embody that positivity with the conviction that Pearl Jam does, most evidently on “The Fixer,” the album’s lead single and the song Bono wishes he could write. “When something’s broke, / I want to put a bit of fixin’ on it,” Vedder sings. The lyrics are reminiscent of Coldplay’s 2005 hit “Fix You,” except that where Chris Martin simpered, Vedder sings with irresistible gusto and belief. “The Fixer” is also the best showcase for the band’s newfound verve; it is propelled by a simple but catchy melody, stadium chant chorus, and exhilarated playing.

The pervasive optimism is part of what makes the album so timely. With the recession in retreat, and hope and change the buzzwords of a new president, Pearl Jam show that it is possible for rock to embody a new, forward-looking American spirit. The album’s hardest rocking songs are also its most exultant. “Gonna See My Friend,” “Supersonic,” and “Johnny Guitar” have short, punky riffs and sing-along choruses. Memorable hooks and melodies have been a trademark of Pearl Jam’s work from the time “Alive” first blasted through radios in early 1991, but these songs show that the band’s most enduring musical gifts are best suited to positive, not depressive, material.

Pearl Jam have finally achieved a kind of comfortable maturity, most evident in the album’s pace. “Backspacer” has several of the slower, contemplative songs that have often been the best showcase for the band’s musicianship and Vedder’s vocals. In the past, the ballads were let down by overbearing, even clumsy lyrics; now, the lyrics are simpler but also more poignant. “Oh, I’m a lucky man / To count on both hands / The ones I love / Some folks just have one / Yeah, others they got none,” Vedder sings on “Just Breathe.” The song has none of the wordplay or metaphor that filled earlier Pearl Jam love songs. But the wistful melody and the subtlest vocal performance of Vedder’s career turn the innocuous lyrics into an achingly beautiful song.

No longer does the tempo alternate only between slow and fast, either. “Among the Waves” is a midtempo anthem whose only real precedent is 1998’s fan favorite “Given to Fly”; like that song, “Among the Waves” has tempered verses that lead into a soaring refrain that perfectly enunciates a vision of triumph.

Perhaps the frenzied vocals and indelible melodies of “Black” and “Jeremy” will continue for decades to move 14-year-olds and aging Gen-Xers to a place that no other band can reach. But for listeners who don’t fit either of these descriptions, “Backspacer” may well be the first Pearl Jam album they can genuinely enjoy.

—Staff writer Keshava D. Guha can be reached at kdguha@fas.harvard.edu.