The 10-piece a cappella ensemble Straight No Chaser (above) returns to the Count Basie Theatre Tuesday. Wednesday brings a sonic summit between scatmasters Manhattan Transfer (below) and Take 6.

Two midweek nights, one famous stage, 20 grand and harmonious human voices.

On Tuesday and Wednesday, the sing’s the thing at the Count Basie Theatre, as the venerable Red Bank venue welcomes a veritable convention of lobbyists for the pop vocalist’s art, in all its jazzy, soulful, boundary-busting glory.

Making an encore bivouac on the Basie boards — their first one outside of the holiday-show season — the 10-piece, all-male a cappella group Straight No Chaser arrives on the momentum of its fifth studio release, The New Old Fashioned, and a live act that’s convinced audiences on several continents that the crowd-pleasing live performers (who emerged straight outta Indiana University) are neither a retro-campy college glee-club, nor a self-important bunch of highly competitive spotlight grabbers. The harmonies are precision-drill-team tight, and the good humor comes naturally when SNC offers up a pitch-perfect Tuesday night tour of “multiple influential musical eras, highlighted by signature and singularly unique medleys.” Tickets for the 8 p.m. show ($39.50 – $59.50) are available right here.

Making their first appearance at the House That Basie Built since the 2014 passing of founding member (and Monmouth County native) Tim Hauser, the Manhattan Transfer carries on in the smoothly swinging pop-jazz tradition that won the group multiple Grammys and the occasional trip to the top of the Billboards (“Twilight Zone,” “Boy from New York City”).

For their 8 p.m. concert on Wednesday, the core ensemble of Cheryl Bentyne, Alan Paul, Janis Siegel and newest transfer Trist Curless celebrate TMT’s 40th anniversary with an event for which they’ve called in reinforcements — none other than ‘Bama-bred a cappella gospel sextet Take 6. Boasting a trophy case of 10 Grammy awards between them — one for every singer there on stage — the combined-forces supergroup promises a set that spans contemporary R&B, songbook standards, devotional pop, imaginatively vocalized rearrangements of jukebox favorites and salutes to collaborators that have ranged from Whitney Houston, Queen Latifah and Phil Collins, to Stevie Wonder, Chick Corea and Bill “Count” Basie himself.

Take it here for tickets ($25 – $55) — and check the Basie website for details on upcoming harmonious events featuring In the Mood: A 1940s Revue (April 24) and the Midtown Men (May 20).