It should. You need to check with Peavey (someone) as to whether or not the speakers on your combo will be disengaged with the cab plugged in. I know on a Valveking it does, but not sure on the Ultra. I'm guessing they would. You also need to find out what the ohms on that cab are. I'm guessing 8 mono but I couldn't read the pic.

So ya.....bump.