4 Ohm Speaker with an "8 Ohm Minimum" Reciever

I drove a pair of 4 ohm bookshelf speakers for years with various "8 ohm minimum" receivers with no adverse consequence.

I was always careful not to crank it, but with a small box speaker I doubt it will stress the receiver much at all.

A resistor is not a good solution. Besides wasting a lot of power, it will cause the frequency response of the speakers to deviate from flatness in proportion to the variations in the impedance vs. frequency curve of the speaker. It will also severely reduce damping factor, degrading bass performance.

I notice that Audio Advisor sells a package consisting of the L54 together with PSB speakers which are specified as 6 ohms nominal, 4 ohms minimum. Also, it would be unusual for an amp or receiver to be designed to truly be limited to 8 ohm speakers. I suspect that calling NAD and also Googling to see what other speakers people have used with the L54 may end up supporting the conclusion that the manual is incorrect.

Regards,
-- Al

My brother was "sold" a reciever with such a warning as part of a package with speakers that were a nominal 4 Ohm load. Needless to say, at anything near loud volume, the the reciever would cut out. These "salesmen" should be ashamed of themselves. Rather than selling the speakers, I would suggest returning the reciever.

I don't know if this is useful in your situation but I used to have a pair of older Monitor Audio 4-ohm speakers that worked quite well with a Parasound amp. When I switched speakers I sold the Monitor Audio's to a friend who planned to use them in his new house.

When he hooked them up to his inexpensive multichannel receiver it almost immediately shut down every time he turned it on. Fortunately, the receiver had an overload protection circuit. I went over to have a look and noticed he was using 18 gauge lamp cord for speaker cable. When we replaced it with the same 12 gauge cable I had been using it worked fine and he's still using the combination several years later. The speakers were just pulling too much juice through too small a wire and the resistance was causing major overheating.

Sfar...What are you thinking!! The smaller wire would slightly INCREASE the impedance seen by the amp and make the load easier to drive. Something else caused the change.