But the pieces with Lewis are the revelations. Nirvana's "Lithium" gets twisted with a recurring hiccup in the meter. (Lewis calls it a "sloshing" take on the song; see "Wendy Gets Bad," below.) Wilco's "Radio Cure" is both stark and cheerful, with first Lewis's solo voice, then rich, thrumming accompaniment from Anderson, then a pause for Iverson's ascending chromatic scale. Throw in the beautifully deployed dissonances and it becomes a down-mood art song.
There are touches like that all through the album, but the difference is Lewis's voice. That shouldn't be a surprise — what can provide a more immediate emotional connection to a song than a human voice singing lyrics? Lewis plays it straight, and the band have given her arrangements that comport. They've actually stripped the bombast out of Pink Floyd's "Comfortably Numb" — no strings, no guitar solo, just Iverson's cascading arpeggios and Anderson providing his earthy bass lines as well as vocal harmonies. When Iverson solos, he's understated, brooding. And the Flaming Lips' "Feeling Yourself Disintegrate" is positively majestic, with tubular bells added into the final chorus.
Of course, in the band's mind, For All I Care doesn't represent a big departure. When I get Anderson on the phone and tell him about my early reaction to their use of covers, he says, "We never do these things as a joke. We play these songs seriously and with a lot of love. People find it amusing because — especially when we first started doing it — it was a novel thing to play rock or pop. People were surprised and didn't know how to react, but we've always done it with a really serious intention."
Aye, but there's the rub. "People didn't know how to react." Don Byron used to like to say, taking his cue from Stravinsky, "Music is objective." Meaning it doesn't care who plays it, but also meaning that its "greatness" can be determined strictly by its musical properties. But how? Both Anderson and Iverson have talked about all music's being on a continuum — jazz, classical, pop. And in that sense, they're no different from classical prodigy Gunther Schuller, who as a child said to his father after hearing "Daybreak Express" on the radio, "Dad, last night I heard a piece by Duke Ellington and it was as good as anything by Beethoven or Mozart."
And yet. For All I Care has sent me back to the Bad Plus discography and given me new appreciation for the way they treat the melody of Tears for Fears' "Everybody Wants To Rule the World" (those Iverson arpeggios again, and even a jazz harmony here and there). And it's given me renewed respect for originals like "Mint," "Physical Cities," and "Cheney Piñata" (nothing if not humor). But, still, music isn't all that objective. It all comes from somewhere. Would I love the Bad Plus's "Life on Mars" if I didn't know the Bowie original? In the Bad Plus's estimation, you'd have to be from Mars not to.
THE BAD PLUS WITH WENDY LEWIS | Berklee Performance Center, 136 Mass Ave, Boston | April 3 at 8 pm | $22-$28 | 617.876.4275 or www.worldmusic.org