ROBIN AND LINDA Williams spent much of the past year writing songs for and performing in "Stonewall Country," a musical about the Civil War campaigns of Gen. Stonewall Jackson, staged this summer in Lexington, Va. And they are frequent, honored guests on "Prairie Home Companion."

But their latest album, "Nine 'til Midnight," draws on neither of those endeavors, catching them instead in a live club performance that gathers new songs, some old favorites and several tunes from their early, long-out-of- print recordings.

For all the album's diversity of moods and textures, what we have here is a seamless performance, as enjoyable for the Williamses' stirring, unsweetened harmonies as for their taste in worthy songs and musicians (Peter Ostroushko is on mandolin and fiddle; Bruce Calin on bass).

It helps, of course, that Robin Williams is such a fine songwriter in his own right. "Whippoorwill," "Haunted Kind" and "They All Faded Away" not only rank among his best work, each imbued with a poignant grace, but also provide splendid showcases for the duo's contrasting yet complimentary voices. Other tunes from Willie Nelson, Townes Van Zandt and the bountiful realm of Public Domain round out this warm and wonderful recording.