Valli, the frontman and only original member still performing with the Four Seasons, launched an extended farewell tour billed “The Last Encores” in October 2023. ALBUQUERQUE, N.M. (AP) — Frankie Valli , whose legendary falsetto defines the sound of the 1960s rock group the Four Seasons, has cancelled the remainder of the band’s 2026 tour dates, citing health concerns. “I’m so sorry to disappoint the folks who have purchased tickets to my shows, but I have decided to take the rest of the year