I have a bigbutt Peavey 1x15 cabinet at our practice space, but it's not quite enough volume so I'm wanting to add something to it. Don't really need more bottom end, need more volume. So, what would you add to the 15? Another 15, or a 2x10? I'm leaning towards the 2x10 so it will be up higher and will add some frequencies that the 15 does not. I know how some people feel about mixing driver sizes and all that though...would the 2x10 reach it's limits way before the 1x15? I guess a 4x10 is an option as well if that would be the best way to go by a wide margin.