I just found out that I can change the impedence on my receiver from 8 ohms to 6 ohms. However, it only does one or the other, and I have a mix of speakers that have different impedences (the m60s and the qs8s). What is the difference between the output with 6 or 8 ohms, and is either way not good for the speakers?

Also, it has 120 watts per channel. Is it even possible for me to damage a set of m60s with that kind of rating?

DS, welcome. The purpose of having a switch or internal setting on a receiver for lower ohm speakers is to satisfy UL(Underwriters Laboratory)safety requirements relating to possible overheating. The lower setting reduces the maximum voltage available, and because of Ohm's Law(power equals volts times amperes; amperes equals voltage divided by impedance)the maximum current and power available are also reduced at the lower ohms setting. The higher setting should always be used, regardless of the impedance of the speakers(even if the manual suggests otherwise for liability reasons)to allow maximum power capacity to be available.

The M60s could handle far more than 120 watts(although in practice this would almost never occur in home use), so this is no cause for concern.

Hey DS, welcome...

I am very surprised how often this question comes up on the forums. I won't even try to top John's response. Anyway, just leave it in the 8ohm position and you'll be fine.

Very cool. Thanks for the info.