It’s been three years since the last album from The Black Keys, the longest gap between records for the Akron, Ohio blues-rock duo, but there’s certainly been plenty to keep frontman Dan Auerbach busy in the meantime. He's been involved in two divorces – his own, marked by a rather surreal battle for Bob Dylan’s hair; and Jack White’s. And he's been producing for artists as diverse as Lana Del Ray and Dr John. In the background of all that, the band seemed to stealthily shift into an arena-filling behemoth, mainly thanks to the radio-friendly direction of 2011’s El Camino. You can understand why Auerbach has suddenly found his diary a little more busy than usual.

Turn Blue, the duo’s eighth LP, suggests that he might also be pretty booked up for the foreseeable. Continuing in a similar vein to El Camino, it’s a record built around soul and R&B, rather than the sparse, scratchy blues that Auerbach and drummer Patrick Carney originally dealt in. Of course, it’s a little disingenuous to still call The Black Keys a duo, given the increasing role that co-producer/co-writer Dangermouse has played in their music since 2008’s Attack & Release. His role, and the change in direction that the band have made since he became involved, feels all the more prominent here on Turn Blue, and ultimately any appreciation of the record will come down to your feelings about that mid-stream switch.

Lead-off single ‘Fever’ gives a good hint towards what you can expect – Auerbach’s raw, throaty vocals stretched over a tight, unashamedly catchy keyboard riff and a bouncing rhythm, a confident track from the same lineage of ‘Gold On The Ceiling’ or ‘Lonely Boy’.

It’s interesting that for a duo who began with just guitar, drums and vocals, a lot of the tracks here focus on other instruments – that organ on ‘Fever’, the insistent bass line that propels ‘Bullet in the Brain’, the strings and angelic backing vocals that weave their way around ‘Year In Review’ – as if the years of restricting themselves themselves has resulted in a build up of creative ideas that are now being unleashed. Hey, you could say the same for ol’ Jack White as well, not that he’d be pleased to hear himself mentioned in the same breath as Auerbach once again.

The thing is, you can see why Auerbach and Carney aren’t going to be spending too much time fretting about moving on from their roots, as the tracks they’re now crafting can be just as impressive for the indie snobs, whilst also appealing to their new audience. ’10 Lovers’ is a great case in point – built around one of Carney’s off-tempo, funk-inspired rhythms, it contains more infectious melodies than most bands could fit in a whole album, but has a casual, swinging air, as if it’s one of many such tracks the band put together in the studio. Nonchalantly writing something so instant is a rare talent, and one that Auerbach seems to have in abundance.

That’s not to say that Turn Blue is a completely ‘pop’ record. Opener ‘Weight Of Love’ seems to have been scheduled to deliberately misguide listeners, opening the album with a folky pastoral strum before giving way to some electrifying rock bluster over an expansive seven-minutes. Lyrically, the album is mired in the gloomier side of Auerbach’s recent experiences, which adds some tone to even its most immediate moments – indeed, the closest ties to the band’s blues-rock roots is probably the over-riding sense that most of what Auerbach is singing about is that a women gone done him wrong, and he’s pretty cut up about it.

It’s a little bit lazy to suggest that Turn Blue simply carries on where El Camino left off, but that’s a large part of what the record represents. It’s definitely more downbeat than its predecessor, and therefore might take a little longer to sink into the skin, but it’s not going to send The Black Keys back to the toilet circuit. If you were hankering for a return to their garage-rock roots, then Turn Blue is going to disappoint; however, if you’ve liked where the band have gone since Dangermouse came on board, you’ll find plenty to appreciate here.