6 ohm speakers, 4 or 8 ohms on receiver?

Question

I have bookshelf speakers from an old mini stereo system as my front speakers, they are rated at 6 ohms. My receiver has a selector on the back to switch between 4 or 8 ohms, I've had it set to 4. Is this the best selection? I never have my receiver louder than 4/10, which is still loud enough to rattle the windows (it's a 5.1 system). I understand ohms is the rating of electrical resistance, which in terms of speakers would mean...the amount of electrical current they can handle, correct? If that's the case am I correct in thinking the receiver should not be putting out more ohms than the speakers can handle? Thanks.

Answer 1

It's fine either way because it' over the 4 ohms spectrum now if the speakers where 2 ohms than it will be a real problem because it will cause a short on your receiver making it unstable but if you decide to get more speakers along with what you have right now like 8 oms than it's best to switch it to 8 ohms it will be safe to hook up 6-8 ohms by leaving the selector in 8 ohms...

Answer 2

Impedance mismatch is generally a bad idea. The first source below says it best under the heading "Can you survive impedance mismatch?"

"I am convinced that the most common question is not 'how can I properly match amplifier and speaker impedance?', but 'how much of an impedance mismatch can I get away with before something explodes?' "

With an impedance mismatch, you're reducing the life of your amplifier, and really shouldn't do it. However, the least unfriendly option of the two is probably a 4 ohm amplifier driving 6 ohm speakers. Solid state (transistor) amplifiers typically can drive higher impedances than their rating demands, although they won't like it and I don't recommend it.

Go buy 4 ohm speakers and eBay the others.

Answer 3

All the current Onkyos have this option also.  It is highly suggested from experts in the audio field to use the 8 ohm setting.  First off in 4 ohm your reciever will run way hotter than normal which may or may not harm the amplifier in the reciever.

Onkyo even claims in it's owner manual to select 8 ohm when using 6 ohm speakers as being best for it's reciever.  The 4 ohm setting should only be for speakers rated at 4 ohms.

Answer 4

I doubt the rating on those is accurate. I recommend not even using them.

Also even though the ohm is used for symbology it is technically called impedance and relates to a characteristic average of overall frequency response.