Robert Plant and Alison Krauss

The Led Zeppelin reunion got all the big headlines last year, but the really good reviews went to singer Robert Plant’s collaboration with bluegrass star Alison Krauss. The resulting album, Raising Sand, produced by T-Bone Burnett, has been nominated for umpteen statuettes in just about every music-awards show you can name, and numerous critics have strained themselves with their gushing praise.

Don’t get me wrong; I like Raising Sand. It’s great to hear a famous wailer like Plant singing softly in harmony with Krauss’s feminine alto. And it’s great to hear Krauss singing outside of her safety zone. But like everything else T-Bone Burnett has done lately, it’s mellow, moody, and a little fussy. It often sounds more like an advertisement for expensive vintage recording gear than it does a showcase for human performances. At its best, all that soft singing sounds like Plant and Krauss playing to each other’s strengths. At its worst, it sounds as though they’re being edged out by the production. Last year I saw a show billed as “T-Bone Burnett and Friends” — in this case, the friends included Neko Case and John Mellencamp. You wouldn’t think those two would have much in common, but Burnett’s arrangements managed to make them sound almost interchangeable.

Judging from the live recordings I’ve heard, Burnett manages to dominate Plant and Krauss’s live performances, too. Still, Plant and Krauss rise above their surroundings in beautiful numbers such as “Killing the Blues,” “Please Read the Letter,” and “Sister Rosetta Goes Before Us.” And, in concert, they’ve been playing “Black Dog” as a banjo-fueled bluegrass number. Okay, T-Bone, I give in: That’s pretty cool.

ROBERT PLANT/ALISON KRAUSS, Humphrey’s Concerts by the Bay, Monday, June 30, 7 p.m. 619-224-3577. Sold out.