This amp has a cool history and is certified awesome. i have a 6505+ combo that is best run out of a 4x12 like you have here. I've got a hankering for gt12-75 so i put one in the combo and my 4x12 is an x-pattern v30 / GT12-75 which is face melting loud. the only bummer with it is that there is a surface-mount pc board that is the chassis and it's prone to having contact lifts which cause it to fade in and out. i had mine fixed by a pro downtown but it was a pia. otherwise i love it. also the logo glows blue at least it does on the combo but mine kind of frizzes on and off randomly, the tech said just turn it off it's unfixable etc i keep it going bc it makes the amp look like its about to blow up '-)