Marantz SR7015 Speaker Ohms

[Phil J N.Z.]

I have read here and on other forums not to change the speaker Ohms setting in the receiver but to leave it at 8 ohms, now I am nervous about this as my old SR6007 blew my center channel and after a lot of research discovered that my center speaker is in fact 4 ohms, all my other speakers are 6 ohms.
The documents with this speaker (B&W) state 8 ohms nominal but checking it with a multimeter it is in fact 4 ohms, I know that the closer you get to Zero ohms you go the closer you are to a short circuit. I don't want to damage my new SR7015 and at the same time want good sound.

Question is what to do am really at a loss to get it right and have been thinking of changing this speaker but what I have available won't fit in the space I have available and it is a true 8 ohms, that way at least I can set the Amp at 6 ohms.

Am semi retired and can't afford to blow this amplifier up.

 

[lovinthehd]

I'd just leave it at the higher impedance setting. Many 8 ohm speakers are closer to 4, too . Try this article https://www.audioholics.com/audio-amplifier/impedance-selector-switch-1

 

[Phil J N.Z.]

I'd just leave it at the higher impedance setting. Many 8 ohm speakers are closer to 4, too . Try this article https://www.audioholics.com/audio-amplifier/impedance-selector-switch-1

Hmmmm, interesting reading, I managed to get a copy of the circuit diagram for this center speaker and the 2 woofers in it are wired in parallel, so it may draw more current at low frequencies, I have it set a large in the receiver so I think I will change it to small and go a bit conservative and set the ohms on the Amplifier to 6 ohms and see if it gets any hotter, it runs quite cool much cooler than my 6007 did.

 

[lovinthehd]

Hmmmm, interesting reading, I managed to get a copy of the circuit diagram for this center speaker and the 2 woofers in it are wired in parallel, so it may draw more current at low frequencies, I have it set a large in the receiver so I think I will change it to small and go a bit conservative and set the ohms on the Amplifier to 6 ohms and see if it gets any hotter, it runs quite cool much cooler than my 6007 did.

If using a sub I'd generally use the small (i.e. use bass management) setting.

 

[Phil J N.Z.]

If using a sub I'd generally use the small (i.e. use bass management) setting.

Yeah am using a sub and already using bass management, odd how the Marantz kept changing my center speaker to large though. Need to override it manually.
Am only using a 5.1 system and it sounds really nice cant see the point in adding more speakers and I dont have the funds to do that anyway.

 

[lovinthehd]

Yeah am using a sub and already using bass management, odd how the Marantz kept changing my center speaker to large though. Need to override it manually.
Am only using a 5.1 system and it sounds really nice cant see the point in adding more speakers and I dont have the funds to do that anyway.

The Marantz shouldn't change speaker setup if you set it up manually unless perhaps a temporary options menu?

 

[TLS Guy]

I have read here and on other forums not to change the speaker Ohms setting in the receiver but to leave it at 8 ohms, now I am nervous about this as my old SR6007 blew my center channel and after a lot of research discovered that my center speaker is in fact 4 ohms, all my other speakers are 6 ohms.
The documents with this speaker (B&W) state 8 ohms nominal but checking it with a multimeter it is in fact 4 ohms, I know that the closer you get to Zero ohms you go the closer you are to a short circuit. I don't want to damage my new SR7015 and at the same time want good sound.

Question is what to do am really at a loss to get it right and have been thinking of changing this speaker but what I have available won't fit in the space I have available and it is a true 8 ohms, that way at least I can set the Amp at 6 ohms.

Am semi retired and can't afford to blow this amplifier up.

You can't check the impedance of a speaker with a multimeter. A multimeter checks the DC resistance of the woofers and nothing else. Resistance and impedance are very different things. You need a woofer tester from Dayton connected to a computer to measure impedance.

 

[Phil J N.Z.]

The Marantz shouldn't change speaker setup if you set it up manually unless perhaps a temporary options menu?

When I first installed it I let the Receiver do it's thing with the sound set up and it set the centre as large with a crossover of 40Hz, as for the surrounds it set them to small with a crossover of 120Hz.
Mains are large and at 40Hz.
I did run it again later on after the amp had bedded in and it switched the centre to large again, so maybe that is the issue software thinking it knows better.

Oh for the simple days of just good Stereo, mind you I do have another rig in my bedroom set up as Stereo and love it.

 

[Phil J N.Z.]

You can't check the impedance of a speaker with a multimeter. A multimeter checks the DC resistance of the woofers and nothing else. Resistance and impedance are very different things. You need a woofer tester from Dayton connected to a computer to measure impedance.

That is some serious kit in that link, is that yours?

 

[lovinthehd]

When I first installed it I let the Receiver do it's thing with the sound set up and it set the centre as large with a crossover of 40Hz, as for the surrounds it set them to small with a crossover of 120Hz.
Mains are large and at 40Hz.
I did run it again later on after the amp had bedded in and it switched the centre to large again, so maybe that is the issue software thinking it knows better.

Oh for the simple days of just good Stereo, mind you I do have another rig in my bedroom set up as Stereo and love it.

So you used the Audyssey feature? The avr manufacturers that used Audyssey often overrode Audyssey's own recommendations when using subs (generally Audyssey advised a starting point of all speakers using small/bass management and a starting crossover of 80hz).

If it set it as large, that's simply turning crossover off except in LFE+Main mode in D&M units where a crossover may also be set. I generally ignore the D&M settings and using subs set up bass management, and may vary crossover depending on speaker capability but tend to higher crossovers with my multiple subs. If you rerun Audyssey it will simply use the latest results for suggestions, but in manual speaker setup you can override such recommendations.