I've asked before, with no replies =( I have an Ampeg 210-SP combo, which I like alot. I bought it at the Guitar Center, where they even told me I could add an extension cab. Well, I can't. I was wondering if I could have somone mod it so I could add a 15" external extension cab (or any cab for that matter), or is it not possible? And if it is possible, would it boost the wattage?