Hello, hoping that someone can help. I have a Nemesis 210 combo, I normally have the Master set to half and the Gain set to something below that. If I try to raise the Gain to half or more it starts to make a high pitched noise, any ideas as to why this is? http://www.eden-electronics.com/nemesis/indiv/nc210.asp Also I'm not up on the handling capacities and Ohm's and things like that could I add the SWR Big Ben 18" cab to the amp succesfully? http://www.swrsound.com/products/customproseries/bigben.html Any help apprieciated.