There aren't any seats up there, but the best vantage point from which to enjoy the Del McCoury Band on Tuesday might have been the crossbeam above the stage of the Barns of Wolf Trap. One would have had a picturesque view of the five members as they created serpentine patterns of movement to the old-time-radio-style center microphone for their solos and vocal turns.

Their music was likewise fluid. Del McCoury's initially workmanlike voice soared to Frankie Valli heights on the gospel standard "Working on a Building," even if it strained a bit on "Let an Old Racehorse Run."

Fiddler Jason Carter and banjo player Rob McCoury, one of Del's sons, likewise exhibited a swaggering confidence. Del's other son, Ronnie McCoury, on mandolin, offered some newgrass-chorded instrumentals and a jack-rabbit-fast playing style that never skimped on subtleties: One could almost hear the breezes his fingers stirred up over the strings. And although most of the band sang at one time or another, it was bassist Alan Bartram, with the band for only two months, whose voice was most surprising, on Hank Williams's "You Win Again." His tenor was limber with youth and tinged with sorrow on this dark breakup song. Here, and on other tearjerkers like Don Humphries's "Take Me to the Mountains" and Richard Thompson's "1952 Vincent Black Lightning," the song's emotional content played hide-and-seek with the players' prowess, in tantalizing bluegrass style.

On the night's jauntiest number, John Sebastian's "Nashville Cats," everyone got a chance to bring a smile: Even Bartram lugged his huge instrument to the mike for three plunking notes, then stepped back again.

-- Pamela Murray Winters