Jack Blacking it
One half of the band that thinks they're the best at rockin' and jivin'. The other half is a guy who uses a pick to pluck a guitar.
Jack Black is the cool one in the band. The other guy is the weird one who talks to the guitar.
In the movie, he's the one who makes the guitar talk. The other guy is just there to pluck it.
He's the one who sings. The other guy just plays the guitar like it's a toy.