Unorthodox speaker wiring

[Pat O'Malley]

I recently bought a home with a pair of speakers installed in the ceilings of three separate rooms each pair of speakers are wired to a volume control installed in the wall nearby each volume control is fed with only one pair of wire for input, for example one volume control has a single pair with the black wire terminated on the L- post and the red wire terminated on the L+ post, the out puts are wired with a pair for each speaker with both red wires spliced together and terminated at the L+ post of the volume control output side and both black wires spliced together and terminated at the L- post of the volume control. Is this arrangement normal? All the wires are routed within walls so running additional input pairs would be a monumental feat. I hooked up each input pair to a speaker selector switch and connected the selector switch to a new Yamaha amp and it worked for a while then stopped, I assume that channel of the amp blew. Anybody have any suggestions?

Thanks

 

[everettT]

What speaker selector switch? Are the VCs impedance matching? What Yamaha? More Information would help.

 

[Pat O'Malley]

The speaker selector is a Monoprice MS-6 6 channel speaker selector, the amp is a Yamaha R-S202. As to the volume controls I must admit ignorance I don't know if they are impedance matching. Is there a way to tell by looking at it? I have had them all out of the wall and there are no manufactures names or numbers tha l can find.

 

[Pat O'Malley]

I have attached photos of the VC if that helps.

 

[everettT]

Thanks for the photos. Not sure why they would have the wires out to the speakers twisted together in that manor. I would put each speaker on its own terminals. Make sure you have the protection circuit engaged on the speaker selector, start with one zone and rewire the VC and check for sound. As for the amp channel being blown can you check it with no speaker selector connected and directly connected to the pair with the corrected VC wiring? It might just be the SS that's fried.

 

[BMXTRIX]

There is only one feed into the volume control and there are two sets of speakers, so the entire system is being run in mono, not stereo. This is (IMO) just a stupid install. Someone didn't know what they were doing and didn't know to run four conductor wire to the volume control, and this is what you end up with.

The Monoprice MS-6 has internal speaker protection, which is likely a good thing to leave on as this load would likely be 4 ohms per location at the very least.

This isn't the more horrendous setup I've seen, and I don't see a clear cut reason why the SS-6 would have an issue with a 4-ohm load being presented to it from every volume control. I just wouldn't expect a bunch of volume out of things overall. Still, at under 20 bucks, that's an incredibly inexpensive speaker selector.

 

[highfigh]

I recently bought a home with a pair of speakers installed in the ceilings of three separate rooms each pair of speakers are wired to a volume control installed in the wall nearby each volume control is fed with only one pair of wire for input, for example one volume control has a single pair with the black wire terminated on the L- post and the red wire terminated on the L+ post, the out puts are wired with a pair for each speaker with both red wires spliced together and terminated at the L+ post of the volume control output side and both black wires spliced together and terminated at the L- post of the volume control. Is this arrangement normal? All the wires are routed within walls so running additional input pairs would be a monumental feat. I hooked up each input pair to a speaker selector switch and connected the selector switch to a new Yamaha amp and it worked for a while then stopped, I assume that channel of the amp blew. Anybody have any suggestions?

Thanks

If you want to run two speakers from one feed, use a jumper to connect the two input terminal sets and connect one speaker to each output set. If possible, set the output of the amp to Mono. If the amp is separate from the receiver, get a summing adapter- Edcor sells them and they're not expensive- far better than blowing an amp and losing part of the music because someone didn't wire the house correctly.

 

[Johnny2Bad]

Those devices with the volume controls in the walls are L-Pads ... they provide a constant impedance load to the amplifier (you can see the transformers in the picture). So, regardless of the other issues, they won't cause the amp to "blow".

I've seen installations like this one before, the idea is to provide "background music" in various rooms rather than HiFi. Ideally there would be a summing adapter that properly combines the L + R channels into mono, or there could be a mono switch on the receiver / amp / etc. that should be used, although that would also affect the main installation. The assumption being that you would not be listening to the main system and the background systems at the same time.

You could convert it to a stereo system if you wanted, but it's a lot of expense if you do just use the remote systems for background listening. You would have to replace the L-pads for stereo units (maybe, they might be stereo already, they do look like mono units, but you would have to check) and do the re-wiring.

See the examples here:

https://www.parts-express.com/cat/speaker-l-pads/306