Re: Bonnie Raitt and George Marinelli - what a great guitar tone!
The magic in his tone, besides the P-90's and his touch, is that Bad Cat amp.
I can't tell which model Bad Cat it is, but I've gotten some of the best blues/roots tones out of Bad Cat, 65 Amps, and Matchless amps. They sound fat and harmonically rich, like no other amps.
And that reminds me of how anxious I am to go to the LA Amp/Guitar Show next week.