OK, I'm thinking of getting a new amp and I need some help figuring out what a few terms mean. First, on a cab (an Ampeg, can't remember the model number) it was listed at 200W or 400W program. What does that mean? Also, on a head (also an Ampeg) is was listed at 200W or 400W depending on the ohms. Again, I have no idea what that means. Can someone please explain to me what these things mean? Also, are there any reasons you wouldn't want a cab to have more wattage than the head powering it? I can understant why you wouldn't want a head that was more powerful than the cab, but I don't know about vice-versa. Thank you in advance to anyone who answers these questions (which are probably pretty dumb questions).