im looking to get a denon avr 3808ci. it says it is rate for 6 and 8 ohms. my front tower speakers are 2 ohms. how does this effect sound? what doed ohms mean? i know it means power some how but not sure. if 2 ohms is lower, shouldnt it be better? my friend said that i should get an amp to run the front tower speakers. what do you guys think?