Your last post cleared up a bunch of things and it showed that the cell spacing had no tweeter area and the Bass Panel backplate which is perfect. I have attached the owners manual to the UB800 and it does say 50 ohms but here is where I am getting mixed up. With your impendance curve at 20HZ it reads 30 ohms and at about 500hz it is about 9 ohms.So where does the 50 ohms specification come from? I didn’t know if the transformers were different or something else at flat settings. That was my puzzling question. It may be if you measure the impendance curve on the woofers, it may be very different. That was my curious question.