Some things take time if you want them to be good -- sourdough bread, bourbon, wine, and music from Catherine Irwin. Irwin's second solo album, Little Heater, arrives a decade after her solo debut (2002's Cut Yourself a Switch), and seven years after she last recorded with Janet Beveridge Bean in Freakwater (2005's Thinking of You), but if Little Heater sounds modest on the surface, it's emotionally powerful and deeply moving music that shows her deliberate pace as a songwriter reaps impressive rewards. Little Heater was produced and recorded by Tara Jane O'Neil, with members of the band Ida providing accompaniment, and the collaboration is an inspired one -- while the music is more artful and adventurous than the stark acoustic backings of Freakwater's best-known work, there's a spare, gentle approach that suits these songs perfectly, and O'Neil strikes a lovely balance between the painterly approach of the musicians and the rough-hewn beauty of Irwin's voice. Sounding like a long lost member of the Carter Family, Irwin sings like a whiskey-addled red dirt angel on Little Heater, and the sweet, unaffected twang of her instrument gently winds itself around the fragile emotional purity of her phrasing, and it brings the spiritual undertow of songs like "Sinner Saves a Saint," "Piss to Gin," and "The Whole of the Law" to life. (Irwin also includes her own interpretation of "Dusty Groove," which she wrote for Kelly Hogan's superb album I Like to Keep Myself in Pain, and it's instructive to compare how two gifted vocalists can find so many different and equally apt things in one great song.) No one else in contemporary music writes and sings with the spectral beauty that comes as second nature to Catherine Irwin, and Little Heater is a lovely, evocative album that touches the heart, the soul, and the intellect with equal force; this is the work of a singular artist working at the top of her game and it demands to be heard.