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Discussion Starter · #1 ·
Hello, I have a question about speakers. If the speakers are 3 OHM and I have a Sony STR-K740P receiver which I think is rated at 8 OHM. Will this hurt the speakers or the receiver? This is for my parents surround sound system that I threw together. Just average use, not turn up too loud or anything?


Thank you,

Robert Smith
 

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Correct expression is speaker impedance (makes you sound less of a noob) and as that AVR doesn't show a rating for speakers that low, I'd suggest don't use them together. It *might* work OK, but there is the potential to damage the receiver.
 

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this is not my area of expertise, but why wouldn't wiring a 4 ohm resistor in line (series) with the speaker not work. it should bring the total resistance up to about 7 ohms, which will be fine for your amplifier. they only cost a couple bucks and then you wouldn't have to worry about it.
 

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Quote:
Originally Posted by LTD02 /forum/post/19615467


this is not my area of expertise, but why wouldn't wiring a 4 ohm resistor in line (series) with the speaker not work. it should bring the total resistance up to about 7 ohms, which will be fine for your amplifier. they only cost a couple bucks and then you wouldn't have to worry about it.

It will make the load safe but it will dissipate half your output power as heat.
 

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Quote:
Originally Posted by moparbob7 /forum/post/19614565


... Just average use, not turn up too loud or anything?

This is the key piece; you'll be fine. There are no issues with real speakers when amps are run significantly below their rated power.


Here are a couple Audioholics links if you'd like to learn why from someone who knows what he's talking about, not just repeating it.
http://www.audioholics.com/education...ector-switch-1

and, even more to the point
http://www.audioholics.com/education...r-or-amplifier


Specifically addressing Onkyos (I have a 707), the 4ohm mode limits power to 35W/ch. The spec sheet says it can deilver 240W/1 ch @ 4 ohms, so I run mine (3ohm MTMs) in 6ohm mode and don't worry about it. The cooling fan has never turned on.


Have fun,

Frank
 

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Quote:
Originally Posted by Eternal Velocity /forum/post/19615687


Why are you getting 3 ohm speakers anyways? You would need a robuts separates amp for that.

may be B&W speakers
 

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Discussion Starter · #12 ·
Just looking at Samsung speaker sets that from the HT-C550 system. Found the set for $25. Just looking for something cheap.


166 WATTS WITH 3 OHM IMPEDANCE

* 2 FRONT (PS-FC550) SPEAKERS

* 2 REAR (PS-RC550) SPEAKERS

* 1 CENTER (PS-CC550) SPEAKER
 

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thanks kal.


most speakers blow 97% of their power into heat anyways and he said his folks won't be blasting the tunes anyways.

http://www.parts-express.com/pe/psho...tnumber=004-20


get four-five of these per speaker.


wire them in parallel and then in series with your speaker.

.

.
..................../ -------resistor--------\\
.................. / -------resistor--------\\

.amp + -----/..................................\\--------- + speaker
..................\\ -------resistor--------/
................... \\ -------resistor--------/

.

.

.amp - ---------------------------------------- - speaker

.

.

this will give you a 5 ohm increase and 40 watts of power (which is more than your folks will be using).


$4 per speaker and you are good to go.
 

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Quote:
Originally Posted by LTD02 /forum/post/19615855


thanks kal.


most speakers blow 97% of their power into heat anyways and he said his folks won't be blasting the tunes anyways.

http://www.parts-express.com/pe/psho...tnumber=004-20


get four-five of these per speaker.


wire them in parallel and then in series with your speaker.

.

.
..................../ -------resistor--------\\
.................. / -------resistor--------\\

.amp + -----/..................................\\--------- + speaker
..................\\ -------resistor--------/
................... \\ -------resistor--------/

.

.

.amp - ---------------------------------------- - speaker

.

.

this will give you a 5 ohm increase and 40 watts of power (which is more than your folks will be using).


$4 per speaker and you are good to go.

Sure but do you think a newbie is capable of this?
 

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Quote:
Originally Posted by moparbob7 /forum/post/19615826


Just looking at Samsung speaker sets that from the HT-C550 system. Found the set for $25. Just looking for something cheap.


166 WATTS WITH 3 OHM IMPEDANCE

* 2 FRONT (PS-FC550) SPEAKERS

* 2 REAR (PS-RC550) SPEAKERS

* 1 CENTER (PS-CC550) SPEAKER

Here's some advice: Do not buy speakers that have been excised from a HTiB. There is good reason that they are so cheap. Buy real speakers, even cheap ones from BB, that are intended to be sold separately.
 

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Quote:
Originally Posted by moparbob7 /forum/post/19616097


Which is better 4 6 or 8 ohms? I have no idea what it is all about? I just buy speakers and go with a high watts...lol


Speakers don't even have watts.


As for which is better, it's hard to really say what I want to say.


All I'll say is that an 8 ohm speaker will give you the easiest time in matching with a receiver.
 

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Quote:
Originally Posted by Kal Rubinson /forum/post/19616258


In this particular case, nothing.

For the first time in a long time when reading something on the internet, I really did laugh out loud. Thanks Kal and moparbob
 
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