I picked up a couple of Eclipse SW8102 subs in the last week, but I'm stumped about the impedence listed in the manual. Everything I've seen online for the subs, including the subwoofer catalog (link to a copy) says that the sub is a dual 4-ohm sub. The problem is that the instruction manual included in the box says that they are dual 3.1-ohm voice coils. My amps (1 per sub) are only 4-ohm stable when bridged (2-ohm stereo), and I don't want to damage it if I run these the wrong way. Any advice (besides getting different amplifiers) would be appreciated.