If the Red Hot Chili Peppers hadn’t lost longtime guitarist John Frusciante, they may not have had anything left to prove. Not after 25 years of documenting their steamy yet traumatizing adolescence (Blood Sugar Sex Magik) and middle-aged transcendence (Californication) under producer Rick Rubin’s watchful eye, and certainly not after the sprawling, two-disc Stadium Arcadium. But with new guitarist Josh Klinghoffer, the Chili Peppers deliver a remarkable album with a clear-cut caveat: embrace the fact that they’re growing up.

Traces of older melodies occasionally surface; Flea’s familiar, jittery bass drives opener “Monarchy of Roses,” and “Annie Wants a Baby” conjures memories of Stadium Arcadium‘s “Death of a Martian.” But Klinghoffer fills in on his own terms. As in the otherwise straightforward “Look Around,” his solos are brief and ethereal, mirroring the spirituality Kiedis sings about. He’s also expanded the group’s approach to songwriting — a number of songs on I’m With You incorporate both guitars and keyboards. Piano-pounder “Even You Brutus?” may mark a sonic sea change, but it complements Kiedis perfectly as he spits out spoken word like a newsboy yelling headlines.

Klinghoffer, who’s nearly 20 years younger than Kiedis, actually learned guitar by along to old… read more »