Anthony "Tony T" DeCarolis and "Wildman Joe" Marchetti are keeping their fingers warm for Oct. 30  when Jolly Weldon throws the grand opening of Jolly's Dueling Piano Bar near Rittenhouse Square (2006 Chestnut St.).

Weldon is promising a happy hour (6 to 8 p.m.), a small-plates menu under $10, and no cover charge at his 125-seat venue.

"Romper Room for adults," he calls it.

The concept of dueling pianos harkens to New Orleans during the Depression. It's been tried around here; a joint at 20th and Arch Streets recently closed after making a go of it for a couple of years.

"From my piano bar [formerly in the Latham Hotel], I saw how the crowd reacted, especially to the rock-and-roll songs," Weldon said. He visited operations in other cities, including Howl at the Moon, Bobby McKey's and the Shout House.

House pianists DeCarolis and Marchetti, who have a 2,000-plus-song repertoire, will play Tuesdays through Saturdays from 8 p.m. on, and will take requests. Their "duel" turns into a giant sing-along. 

The small-plates menu from Brendan Smith of the nearby Smiths restaurant will include blue cheese sliders, mini crab cakes, and flatbread pizzas. Smith and Weldon will do offsite events -- "road show to go" is how Weldon explains it.

Weldon, a D.C. native, came to Philadelphia in 1997 to open the Prime Rib in the Warwick with his brother Garth. The brothers had run the Prime Rib's D.C. outlet.

In 2001, the brothers parted. Jolly Weldon -- that's short for Jolyon -- opened Jolly's American Bar at the Latham. Four years later, he moved into a space on 19th Street, where Smiths is now, for a short-lived sports bar.