• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Question about driving multiple pairs of speakers - mismatched ohms

Murfaman

Murfaman

New Member
I searched around and tried to find this answer but I would like to understand the dangers or precautions to take regarding multiple pairs of speakers.

Receivers (I would never run both at the same time)
Akai AA-1200 (120W)
Sansui 8080 (80W)

Speakers:
Klipsch Chorus II
ADS L810/2

My question mostly stems from the fact that I believe the ADS are 6 ohm and the Klipsch are 8 ohm and I don't know what happens to the source when driving them both together.

Can I run them together off of either receiver or is mixing these pairs a bad idea? Thanks for helping out this cautious noob.
 
Register to hide this ad
Should not be a problem, just keep it out of clipping. A 6 and 8 in parallel gives 4 ohms. I haven't the amps specs as long as they can handle a 4 ohm load. I used to run my Citation on one set and the Marantz 1200 on the other set. Sounded great. You also need to make sure the phase is the same. Some amps outputs are 180 out from the input.
 
Murfaman said:
Receivers (I would never run both at the same time)
Akai AA-1200
Sansui 8080
Click to expand...

Why not?
You can use Y cables to split your source for both receivers (or you can send all of your sources into one receiver and use that receiver's line out into the other receiver) and run one receiver for one pair of speakers and the other receiver for the other pair of speakers.
 
BmWr75 said:
My advice is learn how to appreciate one pair of speakers at a time. Work on speaker placement in relation to your listening position. An equilateral triangle is the typical starting point.
Click to expand...
While I understand your point, it's not really a helpful response. I normally listen to them one pair at a time depending on the material. I've spent hours and hours and inch by inch on placement.

I asked what I did because occasionally, I've run them together at low volumes for a short period of time just to be safe and enjoyed what both pairs bring to the table in tandem, offering two very different presentations that actually play quite well together. Hence my question about the risks of pushing them a bit for longer periods of listening and trying to understand what relationship the ohm measurement has in recognizing a situation that could cause harm to the equipment.
 
opnly bafld said:
Why not?
You can use Y cables to split your source for both receivers (or you can send all of your sources into one receiver and use that receiver's line out into the other receiver) and run one receiver for one pair of speakers and the other receiver for the other pair of speakers.
Click to expand...
I will look into that to make using all my options more convenient. Thanks
 
The formula you're looking for is (speaker A x speaker B)/(speaker A + speaker B). (6*8)/(6+8)=3.4ohms

How well your equipment handles the load depends on what it was originally rated to handle and the volume you're pushing the speakers at.
 
DPotts245 said:
The formula you're looking for is (speaker A x speaker B)/(speaker A + speaker B). (6*8)/(6+8)=3.4ohms

How well your equipment handles the load depends on what it was originally rated to handle and the volume you're pushing the speakers at.
Click to expand...
I suppose what I don't understand is what the effect an ohm rating of 3 vs 8 vs 16 actually means in relation to the stress it creates for the components. What's dangerous and why, and what's something not to worry about. I'm not intending to be an idiot, but I was a journalist and a sales executive. EE is at the polar opposite of my skill set, but at least I'm detail oriented once I understand something. TY
 
Murfaman said:
I suppose what I don't understand is what the effect an ohm rating of 3 vs 8 vs 16 actually means in relation to the stress it creates for the components. What's dangerous and why, and what's something not to worry about. I'm not intending to be an idiot, but I was a journalist and a sales executive. EE is at the polar opposite of my skill set, but at least I'm detail oriented once I understand something. TY
Click to expand...

I'm still learning too.

It takes twice the power to get the same volume out of 4ohm speakers as it would 8ohm speakers so you're pushing your receiver twice as hard. When you're running the 2 sets in parallel (6 & 8ohm in your case) it's the equivalent of running 3.4ohm speakers. I don't know the specs on either of the receivers you listed so you'll have to sort out their ratings and what they can handle. Higher rated speakers aren't an issue, so a receiver rated to handle 4ohm speakers is fine pushing an 8ohm set. The reverse is where you have the potential for problems.
 
Transistor amps will play happily into high impedance loads but will fail into a short circuit, ie zero ohms. The closer you get to zero ohms, the more chance of something going horribly wrong. Pretty much all transistor amps will cope with 8 ohms, and most modern ones will cope with 4 ohms, but going below 4 ohms gets you closer to possible disaster.
Yes, 8 ohms in parallel with 6 ohms gives you 3.4 ohms, but those figures (8 and 6) are really just nominal figures and act as a guide only.
Valve amps cope with a short circuit ok, but transistor amps don't, so transistor amps usually incorporate some kind of protection circuit to prevent (or try to prevent) catastrophic failure when faced with a low impedance load. The protection circuit may utilise a relay to disconnect the speakers, or possibly a circuit to limit the driving voltage to the output transistors.
Anyway, without knowing the details of any specific amp it's impossible to say what will happen with a given load. If you stay above 4 ohms you're pretty safe. 8 ohms is safer still. 3.4 ohms? Personally, I'd be at least a little anxious.
 
Last edited:
DPotts245 said:
I'm still learning too.

It takes twice the power to get the same volume out of 4ohm speakers as it would 8ohm speakers so you're pushing your receiver twice as hard. When you're running the 2 sets in parallel (6 & 8ohm in your case) it's the equivalent of running 3.4ohm speakers. I don't know the specs on either of the receivers you listed so you'll have to sort out their ratings and what they can handle. Higher rated speakers aren't an issue, so a receiver rated to handle 4ohm speakers is fine pushing an 8ohm set. The reverse is where you have the potential for problems.
Click to expand...
Thank you. Makes sense and essentially what I assumed before asking.
 
rothwellaudio said:
Transistor amps will play happily into high impedance loads but will fail into a short circuit, ie zero ohms. The closer you get to zero ohms, the more chance of something going horribly wrong. Pretty much all transistor amps will cope with 8 ohms, and most modern ones will cope with 4 ohms, but going below 4 ohms gets you closer to possible disaster.
Yes, 8 ohms in parallel with 6 ohms gives you 3.4 ohms, but those figures (8 and 6) are really just nominal figures and act as a guide only.
Valve amps cope with a short circuit ok, but transistor amps don't, so transistor amps usually incorporate some kind of protection circuit to prevent (or try to prevent) catastrophic failure when faced with a low impedance load. The protection circuit may utilise a relay to disconnect the speakers, or possibly a circuit to limit the driving voltage to the output transistors.
Anyway, without knowing the details of any specific amp it's impossible to say what will happen with a given load. If you stay above 4 ohms you're pretty safe. 8 ohms is safer still. 3.4 ohms? Personally, I'd be at least a little anxious.
Click to expand...
Perhaps it simply isn't worth the risk with vintage gear, or make sure to only run two pairs of 8 ohm together to keep things at 4 ohms when combined. But even then...maybe just don't. TY
 
DPotts245 said:
It takes twice the power to get the same volume out of 4ohm speakers as it would 8ohm speakers...
Click to expand...
No, that isn't strictly correct. The volume you get out of any speaker is determined by the speaker's efficiency. Some speakers are highly efficient and produce more volume than inefficient speakers regardless of impedance.
However, a given voltage across a 4 ohm load will dissipate twice the power compared to the same voltage across an 8 ohm load.
 
You must log in or register to reply here.
Back
Top Bottom