using 4ohm and 8ohm spkrs together???

[mnnc]

Mixing in a 4 ohm center to 8 ohm set-up???

I have oppurtunity to add a higher quality center spkr to my system (rbh!). However, the center is a 4ohm model while the rest of my spkrs are 8ohm nominal. I use a Boston 7120 recv'r in 5.2 mode and if I am not mistaking the recv'r will handle a 4ohm load. Is it ok to just run the center at a 4ohm load while the other channels are being run at 8? I suppose the recv'r will adjust itself? Thanks.

 

[mnnc]

Have the chance to get a rbh center that is 4ohm. All my spkr's are 8ohm currently. If I add the 4ohm spkr in the mix with the others will my recv'r handle that? I use a Boston 7120. Thank you.

 

[Buckeyefan 1]

Have the chance to get a rbh center that is 4ohm. All my spkr's are 8ohm currently. If I add the 4ohm spkr in the mix with the others will my recv'r handle that? I use a Boston 7120. Thank you.

There's a few major issues in doing this. You'll have to boost the center 3dB's for the impedance difference, and that doesn't take into account the spl rating of the speakers. The 4 ohm may be rated at 87dB at 1 watt/1 meter, and your 8 ohm could be rated at 93dB at 1 watt/1 meter. You then would need to boost the center another 6dB to level out your front stage. That would definitely put a strain on the receiver's center channel output, and could result in distortion when pushed to reference levels. A lot has to do with your room size, crossover integration with your subwoofer, and listening tastes.

The other major issue is tonally mismatching the front stage. Whenever buying a center, always try to timber match the front three speakers. Just because your receiver can handle it, doesn't mean it's a wise idea to mix and match. If your budget can handle it, you're better off to get three identical RBH speakers for the front.

 

[billnchristy]

I would think the 4ohm would play louder because youre going to get more power from the amp.

That being said I have a 4ohm center and 8ohm mains and they were designed for each other and sound beautifully.

I havent checked to see what the Yamaha did to level them, but they sound perfect together.

 

[mnnc]

I appreciate the responses and understand level issues which I can adjust accordingly. Timber match is not that big of an issue to me as most people find it to be. It's been my experience that speakers of decent quality, I mean highly regarded spkr's, will sound good with other spkr's even if they are not same brand for movie viewing. I've payed a lot of attention to what comes from the spkr's during a movie by standing in front of them and I don't get much but off-screne effects. The spkr list almost $700 and I acquired for $125! Unless I find two more like it at that price I will have to use my BA towers for the time being and compare the rbh center with my current BA center.
Are there things I should be aware of that might indicate trouble within amp/recv'r when I use the 4ohm spkr? Thanks again.

 

[annunaki]

PLEASE DO NOT start the same thread in multiple areas. It is not very well liked. Just a friendly warning.

 

[audiohead01]

I currently have a sherwood r965 reciver
LR 4ohm
c 8ohm
rear RL 8ohm.

I have no issues with this at all. The speaker system is actually set-up to be used in this manner.
I have the BG Corp z series set-up with a 210i sub.

good luck

 

[mobb098a]

phillips home thetre systems suck

why are digital amps so weak i have a 300 watt phillips home theater system
and i feel like chucking the piece of shite in the garbage because it seems that my clock radio has less distorsion and more power than it

 

[dp_pb]

most receivers will be fine with a 4ohm centre speaker. occasionally a budget receiver might have problems driving rears at a lower impedance.

if you arent worried about tonal mismatch then give it a go!!

cheers,
dp

 

[Nuglets]

why are digital amps so weak i have a 300 watt phillips home theater system
and i feel like chucking the piece of shite in the garbage because it seems that my clock radio has less distorsion and more power than it

I didn't even know Philips made HT's. I highly doubt that it's a digital amp of any sort. Well, I would have never bought a Philips HT and expected good sound out of it so...I guess you got what you didn't do much research about.

 

[Kolia]

Resurecting threads is fun!

I have a question related to miximg various ohm speakers.

What happens to the relative "loudness" of speakers with different resistance? Setting the system at reference level is fine, but I'm not always listening to movies that loud.
Granted, not all speakers have the efficency. That is part of the channel volume setup conpensation we do.

But won't a 8ohm speaker and 4ohm speaker have a different "output slope"? (Don't know how to call it)

In other words, if I lower the master volume to 70% of reference. Will both speaker's output lower the same amount?

 

[fmw]

There's a few major issues in doing this. You'll have to boost the center 3dB's for the impedance difference, and that doesn't take into account the spl rating of the speakers.

It is the sensitivity of the speakers that would determine how loud they play at a give level of input power, not the impedance. The impedance simply affects the amount of current drawn to reach a given volume level.

 

[Kolia]

Okay, so the amplifier is power regulated?

If I plug a 8ohm speaker and set the amp to give 20W and then swap for an 4ohm speaker, it'll still give 20W, but with more current? (2.5 amp vs 5 amp?)