Chuck and Gap Mangione, the Jazz Brothers, came roaring out of Upstate New York in the early '60s like an improvisational metaphor for the baby boom. Thursday night at Concerts by the Sea, they made a 25th anniversary effort to revive the innocent enthusiasms of that earlier band.
The energy was still there, propelled by the clockwork percussion of Adam Nussbaum and the down-home, let-it-all-hang-out tenor saxophone of Sal Nistico.
But the brothers themselves were surprisingly laid back, with fluegelhornist Chuck playing with a passivity that defied Nussbaum's most fervent efforts to bring the music to life.
Pianist Gap managed to develop a bit more heat, especially on his brother's soul-soaked "Hey, Baby." Yet, his solos, despite their barrage of right-hand frills and flourishes, were a triumph of style rather than substance.