I'm replacing a 10 year old surround AVR. Just ordered a Denon 3802. I was reading downloaded manual and it says impedence of surround speakers should be greater than 6 ohms. My 4 surround speakers (2 rear & 2 side) are 15 year old Canton Plus 4 ohm custom installed into the house. The Denon manual stated that using lower impedence speakers (< 6 ohms) would cause damage and activate the protection circuit, if the speakers were played to loud too long. It did not specify if the amps or the speakers would be damaged, or what defined too loud for too long. I doubt that I would play them too long or too loud. Could I add a 2-4 ohm resistor in series with each of the speaker leads (one per speaker) to increase the overall resistance seen by the amps, or should I just go for it and not worry. My previous surround AVR did not specify and has been running these speakers for over 10 years with no apparent problems. Please respond if you have ideas, experience, or technical knowledge.