It’s a sweltering night in London and the usually cold stone of the Union Chapel offers little in the way of relief: it’s hot everywhere.  Chris Turpin, one half Ida Mae, has broken a sweat before their set has even begun.   It’s the second of two consecutive headline shows at the venue for Josh Ritter with the Norwich duo in support.  Packing not one but two National guitars, the pair are quick to demonstrate their powerful, groove-laden blues.  Turpin’s husky gospel passion is augmented by Stephanie Jean Ward’s pin-point harmonies, delivered with all the righteous sass of a true soul diva.  Ida Mae have been based in Nashville since cutting their debut ‘Chasing Lights’ with Ethan Johns, and have been honing their craft across the States.  As a result, their performance tonight is firmly in the pocket.  From the relative smoothness of ‘Released’ through the rowdy stomp of ‘Reaching’ to the brooding of ‘Chasing Lights’ itself, Ida Mae’s tight-knit set goes down a storm with Josh Ritter’s crowd and packs a serious punch; the knockout blow coming in the form of ‘Sick In Love’, a blues so swampy I’m minded to go directly home and shower.