It isn't the watts that matter as long as they add up to what the head will put out. The important thing is the impedance. The Rumbles that have external speaker jacks are rated for 8 ohms with no external speaker cab and 4 ohms with an external speaker cab. You should never go below the rating for the amp. It will damage it. So, for the Rumbles, when you add external cabs, the total impedance of those cabs should be at least 8 ohms. There are sites that will help you calculate that.Gman, I am seriously green. Now THAT is a stack!
Another noob question for everyone: how can you tell how many "watts" of cabs you can put below a given amp head?
