If 2008's extravagantly titled Med Sud I Eyrum Vid Spilum Endalaust was Icelandic band Sigur Ros' pop album, follow-up Valtari is a return to their quietly soaring, and occasionally cacophonous, past.
The intervening years have been a little fraught, what with shelving their first attempt at a follow-up to MedSud and then going on hiatus.
In the interim frontman Jonsi Birgisson released an excitable and poppy solo album, and Sigur Ros a live album, Inni.
On Valtari they cover familiar territory. Its eight tracks, across 55 minutes, encompass everything from beautiful, eerie, and fragile moods to sometimes noisy, climactic and clamorous ones.
Though the songs are sounding more subdued these days compared to the rousing power they conjured up on 1999's Agtis Byrjun and 2002's ( ).
Take the eight-minute title track, a pure ambient song with slivers of icy sounds shifting in slow motion as lovely chimes ring out, but that's it. Which might be beautiful for fans of the band, yet possibly a little bland for non-believers.
Last track Fjogur Piano is an achingly lonely sounding song, and with lovingly laboured piano-playing, but as it starts to shimmer into life you find yourself willing it to intensify but it never does.
However, there's no denying the immensity of Varuo, with its choral vocals and quietly bristling guitar that escalate to a thunderous percussive crescendo as if the song is about to fall apart. That's when Sigur Ros are at their best.
