The 400+ claims the output is 500W @ 2 Ohms. It doesnt say how many Watts at 4 Ohms. The Ampeg Cab says it will handle 400W @ 4 Ohms. I am eventually going to get a Mesa Roadready 410 Cab for the Mesa 400+ but I dont have the cash right now. Will I in any way harm the Cab by playing the Mesa 400+ through it ? Do I need a Cab with 2 Ohms impedence with this head ? Thanks in advance.