The Black Keys have never been afraid to look backward — especially concerning the blues. The first two tracks of their 2002 debut, The Big Come Up, were lively, low-fi covers of tunes by Mississippi juke-joint bluesmen R.L. Burnside and Junior Kimbrough, and their 2006 EP, Chulahoma, was a full-on, we’re-not-worthy Kimbrough tribute that ended with a voicemail from the late blues belter’s widow telling them how much she loved their renditions.

Kimbrough and Burnside’s rough ’n’ rowdy guitar wailing and foot stomping has fueled the Keys’ own variety of the baby-I’m-howlin’-for-you garage rock. After the band became platinum rock stars, the blues still provided a foundation for the rockier moments of comparatively polished LPs like 2015’s Turn Blue and 2019’s “Let’s Rock.”

Now, on Delta Kream, the Keys are returning to their wellspring, with covers of songs by Kimbrough, Burnside, Mississippi Fred McDowell, and others. They recorded the stripped-back affair in between legs of the “Let’s Rock” tour, but this album couldn’t sound more different. Each of its 11 tracks seem like off-the-cuff recitals of Dan Auerbach and Patrick Carney’s favorite songs, with a little help from two notable journeymen: Kenny Brown, slide guitarist on some of Kimbrough’s best records, and bassist Eric Deaton, a onetime Burnside sideman. 

And while Brown’s easygoing, singing guitar is the clear star throughout the record, something feels off overall, since the renditions here rarely live up to the originals. Although the Keys can still command a Kimbrough-like boogie — “Walk With Me” has an admirably danceable thump, and they redo their stiff-collared Big Come Up cover “Do the Romp,” loosening it up — they don’t add a ton to Kimbrough’s originals. Their “Poor Boy a Long Way From Home” has a distinct Burnside wallop, but since it’s one of the oldest blues songs, period, there are already jaw-dropping versions by Gus Cannon, Bukka White, and Howlin’ Wolf. And it’s hard to imagine anyone turning to Auerbach to hear “Coal Black Mattie,” Ranie Burnette’s ode to a woman who got so drunk she threw her clothes outside.

Mostly, the Keys have streamlined some great blues songs into sleek, rock-leaning jams, sometimes for the better. Kimbrough’s swaggering “Stay All Night” sounds more relaxed here, and they turn Burnside’s barnburner “Going Down South” into an even-tempered R&B number, thanks to Auerbach’s falsetto vocals and a stunning Brown solo. But even at its best, the record sounds like bonus tracks for some more exciting release. Sometimes history’s bounty is best left unmessed with.