A Fleet Foxes cover version posted to YouTube in 2008 brought them buzz, their debut album The Big Black & Blue released in 2010 brought them acclaim, and now First Aid Kit - a.k.a Swedish siblings Klara and Johanna Söderberg - return to face high expectations with follow-up The Lion's Roar. It's a fitting title, really - for it's an album which is bigger, better and bolder than its predecessor. It revisits all that was initially charming about First Aid Kit - but everything is that bit more refined this time around, hardly surprising considering producer Mike Mogis was at the helm (the man behind such indie heavyweights as Bright Eyes and Rilo Kiley).

It's worth remembering that the Söderberg sisters were both born in the 1990s - for, it would seem that in the interim between albums, they've been taking lessons at the Laura Marling School of Writing Folk Songs Far Beyond Your Years. The maturity of their sound can probably be attributed to the experience of those around them in studio - but their lyrics, well, they speak for themselves. Their words suggest that they have well and truly run the gauntlet of life - gone are the fables of their debut, and instead now there's a mournful, nostalgic and at times bleakly poignant honesty. It's not convoluted in any way - simplistic language to convey the simple trials and tribulations of life - and it works for them, brilliantly.

However, this is not to be misconstrued as to suggest that The Lion's Roar makes for a depressing listen - for it does not. There's endearing and even somewhat nourishing warmth to be felt from the ten tracks throughout. The album starts off with an emphatic declaration of intent in the form of title track and lead single 'The Lion's Roar'. Subsequent second single 'Emmylou' follows, a sweet n' soulful ballad which alludes to the great working relationships of country music - Emmylou Harris and Gram Parsons, June Carter and Johnny Cash - the Söderbergs' true affection for the genre shining through. The gradual build of 'This Old Routine' is magnificent, absolutely one of the standout tracks of the album. However, whilst the presence of a full band delights, the simple yet enduring beauty of First Aid Kit backed by a lone guitar cannot be denied either - case in point, the intro to 'A Poet' - a song which serves as perhaps the finest example of the Söderberg sisters' vocal abilities at their best, beautiful refrains and intricate harmonies against a backdrop of sweeping orchestration. The Lion's Roar finishes on a high with the brilliant 'King of the World', Conor Oberst lending his talents to take the lead on verse two as the song ascents into an all-out hoedown.

The Lion's Roar is not without its faults, however. There's a danger that it could veer into background music territory; initial listens may lead to believe that it's very samey - the choruses of 'Emmylou' and 'I Found Away' could be easily mistaken for eachother, for example - but with repeat listens, its full charm will be revealed. Stick with it, and you'll find one of the early 'must-haves' of 2012.

Words: Elaine Buckley