For all the self-conscious dedication with which the roots rockers explore earlier styles, they all seem to overlook the gospel-tinged sound of the 1970s. It only flourished for a few years but this soulful and 'authentic' genre included such powerhouse performers as Joe Cocker, Leon Russell, Janis Joplin and even Eric Clapton. That today's players ignore this material says a lot about how far they've drifted from rock's original foundation in R&B. Gospel is still one of the cornerstones of the mainstream, and the right artist can definitely make it work in a contemporary context. A perfect example is Spiritual Thunder, a local duo that gives the raw emotion of soul an ultracool alternative spin. The secret's in the vocals: Lead singer Pauline Houston has a towering set of pipes, and on the pair's accomplished debut disc, 'Birth,' she wails and moans with such authority that it neatly explains why more musicians don't attempt this style. The production and guitar-work of her partner, Robb McCall, are equally strong. --Ramsey Pennypacker, Philadelphia Weekly.