Making their Severn Records debut, the Fabulous Thunderbirds mark a new beginning with On the Verge, a departure for the blues rockers as they explore their soulful side. Front front man Kim Wilson notes, ''we're defining our own genre.'' With On the Verge the T-Birds have crafted a fresh sound, one that's sure to satisfy diehard fans while bringing new blood into the fold of the band's faithful legion.