The Manhattan Transfer spent Wednesday night at Wolf Trap in fine form, reminiscing in tempo and reveling in four-part harmony.

As always, swing was the quartet's thing for much of the concert. There were contrasting tributes to Ella Fitzgerald (a sultry "A-Tisket, A-Tasket") and Benny Goodman (a rousing "King Porter Stomp") as well as Cheryl Bentyne's lovely reading of Django Reinhardt's "Nuages," sensitively framed by Wayne Johnson's acoustic guitar.

Backed by a versatile five-piece band, the veteran vocal ensemble also moved between bop and doo-wop effortlessly, with Jon Hendricks's witty lyrics paving the way for the former and singer Alan Paul's campy croon and choreography enlivening the latter. The bop recitals, with their tricky intervals, demanded and drew the best ensemble performances, though there was plenty of room left over for Janis Siegel to shine on the gospel-powered "Operator" and for Tim Hauser to indulge his passion for playing the hipster (with bassist Michael Bowie's help) or to unearth an old Eddie "Cleanhead" Vinson blues. Not surprisingly, the quartet saved its hit recording of "Birdland" for the encore, pairing it with a jazz smash from another generation, "Tuxedo Junction."

Singer and keyboardist Vonda Shepard, best known for her appearances on TV's "Ally McBeal," opened the concert with a mildly diverting performance. Whether singing new songs like "Baby, Don't You Break My Heart Slow" or drawing familiar tunes from the "McBeal" soundtrack, Shepard demonstrated great affection for soul music traditions. Unfortunately, her slant on the genre often seemed more mannered than moving.