In Rainbows (2007)

Perhaps not since The Jazz Singer marked the end of the silent-film era has a popular artwork's format occasioned as much hubbub as Radiohead's In Rainbows, which debuted on an untold number of hard drives in the wee hours of Oct. 10. It's not just that the set is download-only; it's that the band, now a free agent, is offering a pay-what-you-will policy on the album website (inrainbows.com), accepting the inevitability of file sharing while appealing to the conscience of its sizable and unusually devoted fan base. (A boxed set, including expanded vinyl and CD versions of Rainbows and priced around $80, will be available later this year.) The strategy's success, despite unconfirmed reports of a million-plus downloads, remains to be seen. However things shake out, it's making for the music-biz Story of the Year.

So what about the music? Despite some dressing up compared with live versions (fans know many of these songs from concerts), Rainbows' 10 tracks are among Radiohead's most straightforward. The electronic swarms that marked 2000's Kid A and 2001's Amnesiac are either gone or folded seamlessly into arrangements. There's empty space here: On parts of the multifaceted opener ''15 Step'' and the quietly unnerving ''Nude,'' you hear just drums and an undistorted guitar, with maybe a modest bass line, behind Thom Yorke's plaintive warbling. Elsewhere, synthesizer washes provide ambient backdrops. And despite a few aggressive bursts — ''Bodysnatchers'' is a flailing rocker that has Yorke wailing ''I'm alive!'' — Rainbows may be the gentlest, prettiest Radiohead set yet.

That's not to say the band's vision has gotten sunny, though the gang of children shouting ''Yay!'' in the middle of ''15 Step'' might give that impression. Many songs are about love and desire, double-edged swords by definition. And the themes cut both ways. ''I love you, but enough is enough,'' Yorke murmurs on the delicate ''Faust Arp,'' which, like ''Nude,'' might refer to an artist's relationship to his fans as well as to a lover. The ballad ''House of Cards'' is that old soul-man trope, the adultery invitation — though in Yorke's hands it becomes something more complicated, as he intones the word denial (in a strange echo of ''Smells Like Teen Spirit'') amid brooding strings and rapturous falsetto.

Some critics have geekily quibbled over the fidelity of the MP3 format, which is slightly less than CD quality. But through decent earbuds on an iPod, or on a burned disc in my car, Rainbows sounds great, well worth the $10 I chose to pay for it. Using the full musical and emotional spectra to conjure breathtaking beauty, the collection is well named. It may have arrived via computer, but the vision is timeless. A

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