6 Ohm speaker set on an 8 Ohm receiver, this OK?

[Steven P. Administrators]

I have a 5.1 Sony STR-DE59 (bought as part of a 5.1 home theater set in 2006) and since the thing still works great (not a lot of mileage in the 11 years I've had it tbh) I am not interested in replacing it since it works fine, but the speaker set  I have for it does need replacing, one satellite doesn't work anymore and the front grill covers have varying damage throughout the years (mainly drops and knocks).

 

Saw this set which are the Onkyo SKS-HT728 - 5.1 and it's in my budget for what I want to pay, but the set it 6 Ohm.  

 

With online search for this question, the answers vary from: the receiver must be the same as the speakers, to 6 Ohm is fine on an 8 Ohm system (as well as) unless you plan to max out volume each time, the receiver could get too hot (I don't).

 

I just wondered what our audiophiles have to say on this matter

 

PS: I confirmed it is the satellite that is broke, because I've tried it on different channels with the same result.

 

[JamesCherrill]

Any amplifier is designed and built for a given nominal loudspeaker impedance to deliver their maximum power.  If the loudspeaker Impedance is higher then then the maximum power will be reduced (but not so much that you would notice). If  the loudspeaker impedance is way lower then the maximum power is also reduced, but with an additional risk that the amplifier may overheat.  Any half-decent amp will be designed with this risk in mind, and will include circuitry to turn itself off before any damage is done.

But... Those impedance figures (Ohms) are not cut and dried for loudspeakers. For a start they vary enormously with the frequency (pitch) of the signal. The impedance is also, in maths terms, a complex number, with phase as well as amplitude. The number they quote is just a simplified average guideline figure.  In practice there's no significant difference between a nominal 6 ohm and a nominal 8 ohm; I wouldn't worry for one second about mixing them.

[Steven P. Administrators]

Decided to go for this (ONKYO HT-S5805) instead, which is €80 more expensive but also has Dolby Atmos in the receiver. So I'll have a 5.1.2 speaker setup and I see the subwoofer is quite a bit smaller (W × H × D) 230 mm × 425 mm × 410 mm 9-1/16" × 16-3/4" × 16-1/8"(incl. projection) than the one included here Onkyo SKS-HT728 (W × H × D): 275 x 507 x 411 mm. The one I ordered isn't far off the dimensions of my current Sony subwoofer (24 mm x 38 mm x 44 mm), which is already set at below 50% level which is fine for my room.

 

Even the wall brackets I bought a couple weeks ago for my current Sony setup have a keyhole adapter which will need to be used with he Onkyo front speakers, which is a good thing