4 Ohm Speakers, 8 Ohm Amps


I own a pair of Vienna Acoustics Beethoven's and a Maestro center channel. I have been using a Carver 806x amp to power all of the speakers (the sides and rears are 4 Waltz's). I have just purchased a pair of Carver Silver 9T's to power the Beethoven’s and I was going to bridge two of the channels on the 806x to accommodate the Maestro center.
I was on the phone with Rita from the Carver Service Center talking about the bridging method, but when I told her I had 4-Ohm speakers she IMMEDIATELY said, "Carver is not responsible for damage to the speakers or the amps." Rita said that they do not recommend driving 4-Ohm speakers with the 806x or the Silver 9T's. I was also told that bridging is not recommended for 4-Ohm speakers. Believe me, I am a little lost because the science of this does not make that much sense, but that is why I am writing this email to solicit ideas and opinions and possibly a solution to my dilemma.

A 4-ohm load will draw more current from the amplifiers. The current may exceed the capability of what the transistors and output stage devices can handle during certain listening conditions. This can cause failure of these devices from excessive heat. If the amp is strained too much from the high current, it will clip. The distortion that follows causes the speaker cone not to move while still receiving power. Since the speaker cone doesn't move, the heat build up is not removed and the voice coil gets damaged.

That's not to say that the amps will sustain damage low volume listening - but if Carver says don't do it...why would you be willing to even consider advice to the contrary?
It will be fine. Most 8 ohm speakers dip to below 4 ohms anyway.. Any decent amplifier can handle a 4 ohm load without much difficulty. If it were mine, I wouldn't think twice about doing it. I've owned numerous 4 ohms speakers before, without any single issue.
Bridging a stereo amp with a 4 ohm speaker means that each amp sees 2 ohms, and many cannot opearate properly with such a low load. A 4 ohm speaker, not bridged, should not be a problem with any decent amp.
I am somewhat new at this but I believe that the problem is that when you bridge the amps you increase the power but the load the the amps see is double as well. In other words the amps will see a 2 OHM load which may definately harm some amps. I am sure there are many members who are able to explain it better.
I wouldn't be too worried about running 4 ohm speakers with the amplifiers in stereo mode, as long as you don't play your music extremely loud!!

I probably wouldn't run a 4 ohm speaker on the bridged amplifier. Does the amp have enough power that you could just use one channel to run the center speaker? If you do this, you might want to take some precautions to protect the unused channel, i.e. put an 8 or 16 Ohm resistive load on it??
I am not a tech,but I had Mission 765's,a 2-way,4 ohm speaker for,hey!,I still have them under the pool table,anyway,I had various amps,some powerful,some not and had no problems.Good luck,Bob