Ohm settings for amp'd LSi9

kirko

Hello,
I just purchased Outlaw 2200 amps monoblocks for my LSi setup (see my sig for details). I'm ready to hook it up but I'm not sure what should I set Ohms to on Onkyo 875 receiver.
Does anyone have any suggestions?

Thank you.

leroyjr1

4 ohms if you're using the receiver to power any of the speakers. For the LSI 9's since you're using a external amp it doesn't matter because you're not using the internal amp to power them.

kolyan2k

leroyjr1 wrote: »

4 ohms if you're using the receiver to power any of the speakers. For the LSI 9's since you're using a external amp it doesn't matter because you're not using the internal amp to power them.

why 4 ohms ? i have been using 8 ohms for at least 2 years now driving my LSI/FXs (before also LSiC)

EDIT: as far as I know it should be 8 ohms unless your AVR uses low quality heat sink (which might be the case with 875 as many people report overheating)

heiney9

kolyan2k wrote: »

why 4 ohms ?

EDIT: as far as I know it should be 8 ohms

Because they are 4 ohm speakers.

No, it shouldn;t be 4 set at 8 ohms. The 4 ohm setting will probably incorporate a current limiter to help keep the receiver from over loading.

Now kolyan2k, if you want to use your 8 ohm setting............more power to you, but it's not really the correct advise for all situations.

H9

kolyan2k

heiney9 wrote: »

Because they are 4 ohm speakers.

No, it shouldn;t be 4 set at 8 ohms. The 4 ohm setting will probably incorporate a current limiter to help keep the receiver from over loading.

Now kolyan2k, if you want to use your 8 ohm setting............more power to you, but it's not really the correct advise for all situations.

H9

and why would you want to limit the current ?

here is an article from Audioholics:
http://www.audioholics.com/education/frequently-asked-questions/connecting-4-ohm-speakers-to-an-8-ohm-receiver-or-amplifier

and this is a quick quote from the article:

"NOTE: Some Receivers have an impedance selector switch. DON'T USE THEM! The manufacturer puts them there for UL approvals as well as easing consumer concerns about driving low impedance loads. These switches step down voltage feed to the power sections which will limit dynamics and overall fidelity. Keep the switch set for 8 ohms regardless of the impedance of your speakers and ensure proper ventilation of the Receiver."

heiney9

kolyan2k wrote: »

and why would you want to limit the current ?

Because a receivers PS is not capable of driving such low impedance's; hence the current limiters.

Don't make me laugh.....I don't read stuff at AH.........they are perpetrators of more BS than I know of. If that's where you get your info from.............I feel sorry for you.

H9

kolyan2k

heiney9 wrote: »

Because a receivers PS is not capable of driving such low impedance's; hence the current limiters.

Don't make me laugh.....I don't read stuff at AH.........they are perpetrators of more BS than I know of. If that's where you get your info from.............I feel sorry for you.

H9

I dont know anything about AH. All I know is that here or at Avsforum I was given this advice (2-3 years ago) to set ohm setting to 8 and for 2-3 years now I dont have any problems. And it makes sense.....if my AVR drives my LSiFXs at 8 ohm without limiting any current, why would I want to limit it ?

leroyjr1

kolyan2k wrote: »

I dont know anything about AH. All I know is that here or at Avsforum I was given this advice (2-3 years ago) to set ohm setting to 8 and for 2-3 years now I dont have any problems. And it makes sense.....if my AVR drives my LSiFXs at 8 ohm without limiting any current, why would I want to limit it ?

Just leave it then.

concealer404

kolyan2k wrote: »

I dont know anything about AH. All I know is that here or at Avsforum I was given this advice (2-3 years ago) to set ohm setting to 8 and for 2-3 years now I dont have any problems. And it makes sense.....if my AVR drives my LSiFXs at 8 ohm without limiting any current, why would I want to limit it ?

It's a safety feature in that case more than anything.

But if you don't want to flip that little switch even after given the reason to switch it to 4ohms, then don't. It's your gear.

dorokusai

Don't worry about that switch, it means nothing.

McLoki

Actually if you are using the receiver strictly as a pre-amp - run the receiver in the 4-ohm setting. It does limit the current and power but you don't care (since you are using external amps to power your speakers) - but in the 4-ohm setting, the AVR will also draw less power and produce less heat as the amps in the AVR idle with no load.

Less heat in your cabinet is usually considered a good thing.

If you are powering your speakers with your AVR - leave it in the 8-ohm setting, but provide good ventilation.

Michael

Jetmaker737

If I was you I'd leave it at 8 ohm setting so you don't current limit your speakers and risk damage due to clipping. As I understand it the issue is heat, so you need to keep an eye on that. See this article (page 6):

http://www.hometheaterhifi.com/receivers/469-a-secrets-receiver-review.html?start=5

You've already taken a load off of it by using the outlaws on your mains. So you're only left with the center and surround for the AVR to drive anyways. All that being said, the Onk 875 will probably drive the 4 ohm speakers just fine on the 4 ohm setting. It was the 876 (and 806) where the amp was seriously down-powered at 4 ohms.

kirko

Thanks,
At this point I'm only running 3 outlaws (mains and center), but I'm actively looking for 2 more. I also built an array of 5 computer (very quiet) cooling fans for AVR, so heat is not an issue.

jparker82

When I added a seperate 2 channel amp to power my LSI 25's it seemed to free up alot of power. My Integra DTR 7.8 now seems to run alot cooler. The statement amp really brought my speakers to life. I also added Nordost blue heaven biwire rev2 at the same time. I am sure that made some diff. I have always been told that the LSI speakers are very power hungry. I am running LSI c, LSI 9, LSI 7, LSI 25(not real happy with built in subs-- I added a definitive and turned one of the polks off) Sort of funny when I am watching a movie and cranking it, my light dim in the house.
P.S.
Makes me laugh with prev post talking about Audioholics, the owner of that web site is on of my neighbors. Not going to comment on him just laugh!!!