Denon AVR1708 won't drive Polk speakers

[Burnedfingers]

Received an email from a friend in regard to his new Denon AVR1708 receiver stating that he cannot use his Polk Audio 5JR's without the receiver going into protection and shutting down.
I am told the specifications for the Denon are for a load of 6-16 ohms and the Polks are 4 ohm nominal. The question is should the Denon be able to power the Polks without the protection circuit turning on? Is the Denon at fault? Is the load too great?

Any suggestions for using the Polks with the Denon? Impedance matching box?

 

[unclejed613]

if he's cranking it up, yes that will happen. another possibility is that he has a shorted rf bypass cap one one of the outputs. if that's the case it will go into protect at low-to-medium volume levels

 

[Burnedfingers]

Thanks for the reply

The unit is still under warranty and has gone back for repair/replacement.

How about hooking the speakers up to an impedance matching box?

 

[unclejed613]

THEthe "impedance matching box" would probably just be a 4 ohm resistor, which if you're buying it commercially as a "black box", you're probably paying way too much. you could probably equip a complete surround system with 4 ohm 50 watt resistors for the price of one "impedance matching box"