The collaborations between former Belle & Sebastian cellist Isobel Campbell and Screaming Trees frontman Mark Lanegan have little to do with either of their respective backgrounds. 'Hawk', their third, presents a pleasant, unobtrusive collection of songs influenced by folk, country and occasionally soul.

The success of Campbell & Lanegan's work together lies almost entirely in the wonderful combination of their two voices. Though on 'Hawk', Lanegan often sounds much less gruff than in the past, there's still a splendid contrast between his rough, gravelly tones and Campbell's airy wisp of a voice. Initially a strange prospect, after three albums together their union now seems to make perfect sense. Having already found their common ground, here the pair mellow out in sweetly harmonised Americana, with a few rock & roll breaks to liven things up.

Interrupting the sedate tone for the old school country rock of 'Get Behind Me' and the distorted brass and familiar bass line of the title track is enough to keep 'Hawk' from falling into tedium. Though the country vibe is the strongest here, Campbell and Lanegan try their hand at soft, mellow soul on 'Come Undone' which echoes the James Brown Classic 'It's A Man's Man's Man's World' with its repeated piano chords. Elsewhere, the duo cover not one but two songs by Townes Van Zandt. The simple acoustic guitar of 'No Place to Fall' fits in perfectly here, while their version of 'Snake Song' with its thumping rhythms and dark bluegrass energy, is one of the album's highlights. Yes, sometimes 'Hawk' feels a lot like background music, but in the best possible way.