Emmy Lou Harris has always had a gorgeous voice, and Leo Kottke has always had quick fingers on the guitar. As they've matured, Harris has gained the confidence and Kottke has learned the restraint to make the most of their natural gifts. Last night at Wolf Trap, Kittke's opening set and Harris' headline set were qualitatively beyond anything they've done on record.

In the past, Harris has often sounded hesitant to unleash the full power of her voice for fear of losing control of the song. Last night she had the confidence to let herself go. On the traditional hymn "Wayfaring Stranger," Harris' voice kept rising until each vowel trembled at the edge of control.

Returning to her old D.C./Virginia stomping grounds, Harris opened the show with Willie Nelson's "Sister's Coming Home." She sang it with the unhibited fervor of a graduating high school senior. She closed the song with a whoop and then shouted, "I'm home!" She further proved her local sympathies by suggesting that Rodney Crowell's "Even Cowgirls Get the Blues" should be retitled "Even the Cowboys Get to Lose" for the evening. The seven country musicians backing Harris more than earned their name, "The Hot Band," with guitarist Frank Beckard shining in particular.

Now that Kottke no longer has to prove just what he can do with a guitar, he can concentrate on making the instrucment more expressive. Last night he picked a complete cast of personalities out of his guitars. The fine nuances of his voicings made some notes bounce out playfully and others break off decisively. Some phrases built a furious charge while others whipped intimately. Kottke only sang three numbers allowing his far more eloquent instrument to carry the rest.