My center is rated 6 ohm with max wattage of 400, and fronts are rated at 8 ohm with max wattage of 200. My surrounds are 8 ohm with max wattage of 150. I'll be using the AVM 20 as my processor. I'm looking at 7 channel amps now, but I'm not sure if I should get a 200 watt amp (sherbourn or b&k) or 105/125 watt (PVA 7). None of the top amps are rated at 6 ohms...they're all 8/4/2. I'm wondering which way to go? Would the 200 watt amps overpower my surrounds? Would a 105 amp be too little for my center channel?