It was a confab of crooners young and old at Patsy’s Italian Restaurant on West 56th Street when Michael Bublé sat a table away from Frankie Valli on Sunday night.

Spies said Bublé, 38, was with family including wife Luisana, baby Noah and grandfather Demetrio, while Valli, 80, was celebrating the opening of Clint Eastwood’s movie “Jersey Boys” about his career with the Four Seasons.

The joint’s chef, Sal Scognamillo, came out of the kitchen to introduce the singers who’d never met — and a spy said, “Bublé told Valli he’d try to perform some of Valli’s classics, but doesn’t think he can hit all the notes.”

Scognamillo then treated both tables to a dessert not found on the menu: sfogliatelle napoletana.