4 OHM loads driving them?

[ahblaza]

Hello,
I thinking of putting a second HT setup together, I have an Onkyo TX-SR702, mains preout to external amp. I'm considering 3 Behringer Truth 2031P's as a center and side surrounds, since I will only be using the center and surround amps of the 702, will I have trouble driving the 4 Ohm loads of the 2031P's. After reading an older review of the Onkyo TX-SR601 by Clint DeBoer here at AH, he had no problem driving his 4 Ohm Axiom M80's and six Ohm center and surrounds all from the 601's amp section. I don't know how to put up the link of the review but here it is. www.audioholics.com/reviews/receivers/onkyo-tx-sr601-6-1-home-theater-receiver Onkyo support says it will work but may cause serious damage to receiver, speakers or both. Thanks for listening.
Jeff

 

[TLS Guy]

Hello,
I thinking of putting a second HT setup together, I have an Onkyo TX-SR702, mains preout to external amp. I'm considering 3 Behringer Truth 2031P's as a center and side surrounds, since I will only be using the center and surround amps of the 702, will I have trouble driving the 4 Ohm loads of the 2031P's. After reading an older review of the Onkyo TX-SR601 by Clint DeBoer here at AH, he had no problem driving his 4 Ohm Axiom M80's and six Ohm center and surrounds all from the 601's amp section. I don't know how to put up the link of the review but here it is. www.audioholics.com/reviews/receivers/onkyo-tx-sr601-6-1-home-theater-receiver Onkyo support says it will work but may cause serious damage to receiver, speakers or both. Thanks for listening.
Jeff

It won't damage the speakers, but might the receiver. I suspect it will be fine, but since loudspeaker manufacturer and receiver manufacturer publish minimal specs, you won't know for sure until you try it out.

 

[jp_over]

I'd drop a quick e-mail to Onkyo and ask them directly.

 

[TLS Guy]

I'd drop a quick e-mail to Onkyo and ask them directly.

They will say don't do it, as they won't know the load presented by that speaker any better than I will. Unfortunately the impedance spec given by a manufacturer is pretty much useless.

 

[Rickster71]

Since the speakers have an SPL of 89 dB 1w /1m, and he's using them for rear surrounds. (if I under the op correctly)
I'm wondering if it would be OK if not played at reference levels?

 

[TLS Guy]

Since the speakers have an SPL of 89 dB 1w /1m, and he's using them for rear surrounds. (if I under the op correctly)
I'm wondering if it would be OK if not played at reference levels?

I too suspect it will be fine, but no guarantees!

The real problem is receivers and not the speakers. People just need to avoid gear that has any chance of being blown up by a four ohm load. Building gear like that in this day and age just is a total aggravation.

 

[ahblaza]

They will say don't do it, as they won't know the load presented by that speaker any better than I will. Unfortunately the impedance spec given by a manufacturer is pretty much useless.

Mark, that is what onkyo said when I emailed them. I could be safe and go with 2030's, it is rated at 8 Ohm, but I like the 8.5" driver of the 2031. Like you said I won't know till I give it try, I really don't want to fry the receiver. Would the receiver be better ( or less of a chance of receiver frying ) at driving a single Behringer 4 Ohm 2031P? Thanks for yout time.
Jeff

 

[KEW]

Based on this, It kind of looks like it is a 4 ohm capable, but it is wierd they left the 8 ohms blank so maybe it is a typo.

http://www.onkyousa.com/model.cfm?m=TX-SR702&class=Receiver&p=f

Have you considered a 2031P for your center and 2030P's for the surrounds?
If Clint could drive a pair of Axiom 80's along with center and 6 ohm surrounds at decent levels with the 601, I'd think the 702 would have no problem with one 4 ohm speaker and a pair of 8 ohm speakers.
(I think you'd be fine with the three 2031's, but wouldn't want to bet my first born on it!)

Cheers!

 

[zieglj01]

Based on this, It kind of looks like it is a 4 ohm capable, but it is wierd they left the 8 ohms blank so maybe it is a typo.

http://www.onkyousa.com/model.cfm?m=TX-SR702&class=Receiver&p=f

Have you considered a 2031P for your center and 2030P's for the surrounds?
If Clint could drive a pair of Axiom 80's along with center and 6 ohm surrounds at decent levels with the 601, I'd think the 702 would have no problem with one 4 ohm speaker and a pair of 8 ohm speakers.
(I think you'd be fine with the three 2031's, but wouldn't want to bet my first born on it!)

Cheers!

Just watch the volume level - the Onkyo's tend to run hot - they should be able to handle one 4 ohm speaker.
The description says 4 ohm capable - with Onkyo, you never know.

 

[TLS Guy]

Mark, that is what onkyo said when I emailed them. I could be safe and go with 2030's, it is rated at 8 Ohm, but I like the 8.5" driver of the 2031. Like you said I won't know till I give it try, I really don't want to fry the receiver. Would the receiver be better ( or less of a chance of receiver frying ) at driving a single Behringer 4 Ohm 2031P? Thanks for yout time.
Jeff

It is just impossible to say. The amp speaker interface is a can of worms at the best of times. The industry have been resistant to publishing a speaker amp torture index. Even an impedance curve does not tell the full story.

I maintain every amp/receiver should at least be stable to four ohms and preferably below.

This interface issue is the reason, I'm sure that people report such variability in the same model of receiver. It is the speaker load difference given adequate ventilation.

 

[ahblaza]

Based on this, It kind of looks like it is a 4 ohm capable, but it is wierd they left the 8 ohms blank so maybe it is a typo.

http://www.onkyousa.com/model.cfm?m=TX-SR702&class=Receiver&p=f

Have you considered a 2031P for your center and 2030P's for the surrounds?
If Clint could drive a pair of Axiom 80's along with center and 6 ohm surrounds at decent levels with the 601, I'd think the 702 would have no problem with one 4 ohm speaker and a pair of 8 ohm speakers.
(I think you'd be fine with the three 2031's, but wouldn't want to bet my first born on it!)

Cheers!

Kew, no I have not considered that but now I certainly will, thanks for the suggestion
Jeff

 

[j_garcia]

I have installed the 601 previously and it is a pretty stout receiver, but I would not expect it to adequately drive 4 Ohm speakers for long periods or at reference levels realistically. Having said that, if you aren't going to be demanding high SPLs from the system, it WILL work. The 2030s are small enough and don't go deep enough that I would not expect them to present a load that is too difficult to drive for your receiver, especially with them crossed over.

The good thing is the 70x have preamp outs so if it becomes an issue, you can add amps

Driving a low impedance load will more likely cause damage to the speaker first in the near term and to the amp long term due to heat if it can't handle the load. Clipping will occur much sooner when an amp can't handle low impedance loads and that is what kills drivers faster than anything.

 

[ahblaza]

I have installed the 601 previously and it is a pretty stout receiver, but I would not expect it to adequately drive 4 Ohm speakers for long periods or at reference levels realistically. Having said that, if you aren't going to be demanding high SPLs from the system, it WILL work. The 2030s are small enough and don't go deep enough that I would not expect them to present a load that is too difficult to drive for your receiver, especially with them crossed over.

The good thing is the 70x have preamp outs so if it becomes an issue, you can add amps

Driving a low impedance load will more likely cause damage to the speaker first in the near term and to the amp long term due to heat if it can't handle the load. Clipping will occur much sooner when an amp can't handle low impedance loads and that is what kills drivers faster than anything.

Thanks John, it's rediculous to even attempt this, as you say the 702 has preouts to add amps, that is a much better solution and a safe one. Thanks again.
Jeff