The credibility of blues-rock has ebbed and flowed wildly for 40 years. Once upon a time it was simply the common currency for all major British and American rock bands, as exemplified by Led Zeppelin. Punk’s Seventies heyday put the kybosh on all that and blues-rock has been a less loved creature since, redolent of lazy parochial pub jam bands. However, from George Thorogood and the Destroyers to the White Stripes via Mississippi’s Fat Possum Records, it’s also become a major niche flavour for connoisseurs of raw guitar Americana - the scuzzier, the better.

Although a relatively new name around these parts, Kathleen Edwards has been alt-country’s nearly girl for almost a decade in her native Canada (as well as the doyenne of many campus radio stations across the States). But praise goes much further. Dylan likes her almost as much as Sheryl Crow, the Stones have had her on tour and in fact almost everyone who listens to her enjoys the way she injects warmth and lightness into musical styles normally bowing under the weight of earnestness. Voyageur, her fourth LP, has an even easier manner than before.

Before the internet and the Kindle were invented, generations of Americans saw their lives refracted through the pages of Life magazine. In particular, through its photography, since writers at Life were largely relegated to supplying glorified picture captions. They were also allowed to carry the photographers' equipment.

Nova Scotia-born Leslie Feist is the very model of a 21^st-century artist: independent in spirit yet able to work the mainstream industry to her advantage, technologically savvy and au fait with all the means to build and sustain a profile and sales while still maintaining some sense of artistry and dignity.

“Cocaine Blues” is a song whose murky origins lie at the very roots of blues, folk, country and rock’n’roll, possibly right back to the last days of minstrelsy. When Johnny Cash performs it on his riveting 1968 live album At Folsom Prison, it fairly hums with potency, just about as heartening as popular music gets. When Merle Haggard has a crack at “Cocaine Blues” on his latest album, however, the mood is the polar opposite. The clean easy-going tone conjures a country and western version of Hugh Laurie’s recent sedate, chart-bothering take on the blues.