Taking its cue from that great harmonic convergence, Lambert, Hendricks and Ross, the Uptown Vocal Jazz Quartet engages in a lot of challenging wordplay and chordplay on "Half Past Swing." The group's winning vitality and ease prevents the album from becoming just another sentimental journey.

There's something inherently appealing about the ensemble's vocal blend. No matter if the tune is swift or sultry, Ginny Carr, Robert McBride, Lisanne Lyons and Roger Reynolds achieve a seemingly natural vocal chemistry. Among other things, they bring the requisite quotient of cool to the Jon Hendricks and Dave Lambert lyric "I'm Sand, Man," impart a dreamy air to the romantic musing "Close Your Eyes," and charge Duke Pearson's bittersweet rhapsody "Jeanine" with sweeping and vibrant harmonies. Like Lambert, Hendricks and Ross, the UVJC also swear allegiance to Count Basie's brand of imperturbable swing, as its languid reprise of "Li'l Darlin" readily attests.

Throughout much of the album, David Nokes plays the group's silent partner with finesse, fashioning a series of smart, colorful and harmonically tricky arrangements that capitalize on the quartet's vocal dexterity. With help from plenty of local musicians, including pianist Wade Beach, guitarist Paul Wingo and saxophonist-arranger Chip McNeil, the Uptown Vocal Jazz Quartet ultimately make a particularly demanding aspect of jazz performance come alive.

Appearing Friday at the Ice House in Herndon and Saturday at the Theatre at Washington, Va. To hear a free Sound Bite from Uptown Vocal Jazz Quartet, call Post-Haste at 202/334-9000 and press 8131. (Prince William residents, call 690-4110.)