Prewired home...How to connect sub (4 wires)

[brionwarren]

Hello,
My house was prewired for a 5.1 system. The guy told me he wired "in wall"a place to connect my subwoofer. I unscrewed the plate and there are 4 wires. What do I do with them? what do I need to connect them to my polk 10 inch sub?

yes, i am a rookie. Everything else is great though.

brion

 

[Adam]

Welcome to the forum, Brion!

A couple of questions for you:
1. Regarding the four wires - what type of wires are they?
2. What is the model number of your Polk sub?

Thanks.

Adam

EDIT: One more question - did the plate that you removed have connectors in it?

 

[brionwarren]

thanks for responding

There is a hole in the plate where the cable can go through. It says cm-cl2 in it is 4 colored wires...

the sub is a polk psw 10

no connecters.



same cable on end of house where the audio rack is. positive it is the "other end"

 

[Adam]

Alrighty. I'm going to bet that the cable that is in your wall is a four-conductor unshielded speaker cable. Ideally, it would be a shielded 75-ohm cable that you would use with the line-level subwoofer output from a receiver. There are ways to make that work if you really want to use the in-wall cable, but you'll have to see how well it works for you. Others here may recommend fishing a different cable through the wall instead of what you have there right now.

If you can just as easily run a cable straight from the receiver to the sub, that's what I'd suggest. If you want to use the in-wall cable, then there are two things that I'd try, neither of which is ideal:

1. Try using the unshielded cable to run the line-level signal from your receiver's subwoofer output jack into the line-level inputs on the sub. You'd need to attach RCA connectors to each end of the cable. I'm leaving at the moment and don't have time to go into that, but I can later. The potential downside is that the lack of shielding may result in a hum being heard from your sub if the cable picks up sufficient interference.

2. Use the unshielded cable for speaker-level connections instead. Connect the front left/right speaker outputs on the receiver to both your front left/right speakers and to the speaker level inputs on the sub. [NOTE - I would want for others here to bless hooking those up in parallel before you do that, as I think I read that is okay, but I'm not certain.] You would then set up your receiver so that your front left/right speakers were set up to receive bass from other speakers as well as the LFE channel.

If there are two four-conductor cables, then you can improve on option #2 quite a bit, so let us know if there are two cables instead of one.

 

[brionwarren]

ok

There is only one of those cables. It does have a 4/c on there. Honeywell 4/c cm cl2.

The reason I want to use this for the subwoofer is beacause of its location. It cannot be re-wired.

I think I will have to choose option 1 and hope for no interference. Can you help me on what I need to get? Sounds like 2 connects--1 for the sub and 1 for the reciever.

 

[Adam]

Unless your receiver has two subwoofer outputs, then I'd suggest a single RCA connector on each end. Then you'd use a y-splitter to go from the single RCA connector coming from the wall to the two inputs on the sub (the manual seems to recommend using both inputs on that sub).

My pooch is getting anxious, so I gotta go take her for a walk. If no one else chimes in, I'll be back later to try to talk you through putting on those connectors (if I can find a good reference for myself to learn how ).

 

[ParadigmDawg]

Adam, how many times do I have to tell you. Your wife wants to be called honey not pooch and she wants to go out for dinner, not for a walk....

My pooch is getting anxious, so I gotta go take her for a walk. If no one else chimes in, I'll be back later to try to talk you through putting on those connectors (if I can find a good reference for myself to learn how ).

 

[ParadigmDawg]

You just need something like this http://www.bhphotovideo.com/c/product/515880-REG/Phoenix_Gold_QRCMB_QRCM_B_RCA_Terminals.html

Rat Shck should have them and you can use some heat shrink to make a clean install.

 

[brionwarren]

thanks

I'll give this a shot.

Here is what I think you are saying.

Go to the shack....get a connecter the wires go through that y into my 2 sub inputs Left and right.


question: do I use all 4 wires in the speaker cable (2 and 2) or do I use 2 wires (red and black) only.
(The cable coming out of the wall has 4 wires)

 

[ParadigmDawg]

I would twist the blacks together and the reds together so you have a larger AWG. Look for RCA plugs that either use a compression system or lock screws unless you are handy with a soldering iron. I doubt that you need the y-connector but they are 4 bucks at RS so grab one while you are there.

...and hurry...the Rat Shack closes in 15 minutes....

 

[brionwarren]

on my way

I really appreciate your help. Will post the results later

 

[brionwarren]

not quite there

hello again

I'm doing something wrong. I have the rca jack and twisted the red wire aaround the screw and plugged in into the woofer right and and also tried the rca with a y connector going into both right and left. Neither worked.

Then I twisted red and black together into the rca connector. still no luck.

any ideas?

 

[Adam]

Just to be complete in my thoughts, here's one way to do it:

1. RCA cable running from the receiver's subwoofer output jack to the RCA connector that you put on one end of the in-wall cable
2. Single-side of RCA y-splitter plugged into the RCA connector that you put on to the other end of the in-wall cable (you might need another RCA cable in between if the sub is too far away from the wall plate)
3. Double-side of RCA y-splitter plugged into the left/right line-level inputs on the sub
4. Make sure that the sub is on
5. Make sure that the receiver is set up to run the sub (i.e. subwoofer set to on, speakers set to small - we can help you better with this if you tell us which receiver that you have)

You can troubleshoot if it's the in-wall cable/RCA connectors by directly plugging the sub into the receiver and bypassing the in-wall cable. If it works when connected directly, but doesn't work when using the in-wall cable, then we know that's where to focus.

I'll post again when I put together how I'd connect the RCA connector to the in-wall cable.

BTW, what type of RCA connectors did you buy? Male or female?

 

[brionwarren]

hi

male connectors rca

then a female y to connect into the subwoofer


reciever is a brand new onkyo sr 606


I have used it with a yellow video rca jack and the sub works fine.

Sub is on on my my reciever

thanks

 

[Adam]

Would you mind posting a link to the connectors that you bought, or just give me the part number from the package? I'm assuming that you got them at Radio Shack based on the other posts.

Thanks!

 

[brionwarren]

right angle rca

http://www.thefind.com/instruments/browse-solderless-rca-plugs

I got the right angle kind because they were out of the other

http://www.thefind.com/instruments/browse-solderless-rca-plugs

 

[brionwarren]

checked sub again with direct cord works great

off to my son's indoor soccer game will be back to see if you learned anything


this is a great site.

 

[Adam]

I hope that the game was fun!

I'm doing something wrong. I have the rca jack and twisted the red wire aaround the screw and plugged in into the woofer right and and also tried the rca with a y connector going into both right and left. Neither worked.

Then I twisted red and black together into the rca connector. still no luck.

any ideas?

You mention connecting one wire (or two wires twisted together) onto the screw of the RCA connector. However, the RCA connector should have two connections to the wire - there is a signal wire and a return wire. So, one wire connects to the center core, and another wire connects to the outer sheath.

Did the connector come with any instructions? If so, there is hopefully a diagram. You can also check out the final page of this PDF document - the connector is surely different than what you bought, but it gets across the concept.

 

[Adam]

Also, once you get that all working, I have a suggestion for a cleaner install. I have the impression that right now you have a wire coming out of a wall plate that has a hole in it. You can buy inexpensive wall plates with RCA connectors on them.

You could get RCA connectors that have a female jack on one end with the other end open to bare wire, but I'd go with a wall plate connector with female jacks on both ends. That way, you could more easily disconnect from the in-wall cable (that would have a male connector attached to it).

You can get those at Home Depot and other places. I bought some wall plates and speaker binding post inserts from Parts Express and was very pleased with the quality, pricing, and delivery. Their main listing of wall plates and inserts is located at the link here, and I'd be happy to point out specific suggestions.

 

[brionwarren]

back

Hi, I am getting closer. I understood your directions. The rca jacks I got are real cheap. verry difficult to put the "wire" through the tiny ground hole. And the ground is so close to the other connector that it is a mess.

However I followed instuctions and it didn't work.

Before I give up, I am wondering.....I am only using the red and black wires, Do you think that is the problem? the green and white are just sitting there.