Ok, got a response from Rotel and it isn’t pretty. I will let you read it for your self.
“Basically, the amplifier is bridged so that now it sees 2 ohm speakers instead of 4 ohm speakers. This will generate a lot of heat from the unit. In the long run the heat could eventually cause the amplifier to fail or, depending on how hard you drive the system, something to blow up. If you can keep the amp cool enough during use then you will notice that it works but your distortion rating when running in bridged mode plus 4 ohm speakers is going to be about eight times greater than normal.”
This gave me some major concern, so I decided to check if I had done any damage. I turned all the bridging off and checked each of the channels. The first one was DEAD (Oh No!!!). The other 5 seemed OK (whew!!!). Well I popped the cover off (love that power supply) and found a fried fuse. A quick trip to Radio Shak and I am up and running again. However, instead of bridging, I am bi-amping the M80’s (as per Rotel's recomendation inplace of bridging). I would say the difference is subtle (better), but it is noticeable. And because the 976 has variable gain controls on the front, I can customize the volumes of the highs and lows. I think Axiom got the crossovers in the M80's correct, because I perfer the sound with both being neutral. However it is nice to be able to tweak it a little.
Interesting to me all the huge money spent on exotic speaker cables and inter-connects when the signal still has to travel through a glass tube with a wire in it about .5 millimeters in dia; called a fuse.
Anyway Rick, thanks for the heads up. This probably saved me a lot of grief down the road.
Does anybody know how the math works on this? If I have an amplifier delivering 100 watts into 4 ohms and I bi-amp the speakers does that give me 200 watts?
