The ‘90s country superstar digs deep into her roots here. Nashville-bred Morgan (her dad was ‘50s country king George Morgan) taps her inner countrypolitan crooner on a cover of the Patsy Cline B-side “Strange,” with an Owen Bradley-esque arrangement to match. The inherent soulfulness in her voice is underlined in an achingly spare, subtle take on Bobbie Gentry’s “Ode to Billie Joe.” And Letting Go … Slow isn’t all covers; even new tunes like the steel guitar-soaked weeper “Lonely Whiskey” and wanderlust ode “Something About Trains” take on a timeless quality.