Quick wiring question.

[collegeaudio]

Im running a Sony STR-DB940 (pdf available here: http://www.docs.sony.com/release/strdb940.pdf) for a receiver and have a few questions with the wiring of a sub. It's a Polk PSW505 (pdf available here: http://www.polkaudio.com/downloads/manuals/home/PSW303_404_505Manual.pdf) You can view the hookups here: Newegg.com - Polk Audio PSW Series PSW505 12" Powered Subwoofer Each

So, my understanding is that I have a few options for hooking this sub up, from what I can see. The sub features speaker in and out connections, Line In (Filtered) and LFE In (unfiltered). Which is the most ideal setup for my receiver? I was assuming I would be using a sub wire to connect my sub-out to the receiver, but with l/r speaker connections I'm not so sure anymore. What are the advantages/disadvantages of using that instead?

 

[Adam]

With the filtered inputs, both line level and speaker level, the Polk is going to apply it's own internal low-pass filter based on where you set the "LOW PASS" dial on the sub.

With the unfiltered input, the sub will play the signal as received.

If you are using your Sony to do the bass management (which most people do), then connecting one of the Sony's subwoofer outputs to the Polk's unfiltered LFE input is the way to go, IMO.

 

[collegeaudio]

Thanks. So all I would need is a digital coax, like this one?

For only $4.28 each when QTY 50+ purchased - 15ft High-quality Coaxial Audio/Video RCA CL2 Rated Cable - RG6/U 75ohm (for S/PDIF, Digital Coax, Subwoofer, and Composite Video) | High Quality RG6 Digital Audio 24K Gold-Plated Cables w/ Fancy Connector

 

[Adam]

Thanks. So all I would need is a digital coax, like this one?

Yep, that'll do it. You can actually use any RCA cable, but one like that with better shielding is nice. If you have some RCA cables around the house, video cables tend to have more shielding than audio cables - and you can easily tell because the cables are thicker.

 

[collegeaudio]

Quick bump with a problem.

I finally got around to hooking up the sub with the coaxial cable and the receiver doesn't seem to be outputting anything to the sub. The cable seems fine, if I connect the cable to the unfiltered LFE and grab the other end, I can generate sound from the sub. However, neither sub outputs seem to be sending any signal to the sub. Do I need to be playing through a certain mode for it to send output to that channel? Using my ipod/laptop and a 3.5mm to 2 RCA cable, none of the inputs seemed to change anything.

 

[j_garcia]

Quick bump with a problem.

I finally got around to hooking up the sub with the coaxial cable and the receiver doesn't seem to be outputting anything to the sub. The cable seems fine, if I connect the cable to the unfiltered LFE and grab the other end, I can generate sound from the sub. However, neither sub outputs seem to be sending any signal to the sub. Do I need to be playing through a certain mode for it to send output to that channel? Using my ipod/laptop and a 3.5mm to 2 RCA cable, none of the inputs seemed to change anything.

Go into the speaker setup in the receiver and set some or all of your speakers to small, make sure the sub is set to ON or YES.

 

[collegeaudio]

Go into the speaker setup in the receiver and set some or all of your speakers to small, make sure the sub is set to ON or YES.

Speakers are set to small and the subwoofer is YES. It's even lit up on the display, yet it doesn't seem to be working.

Anything I might be missing?

 

[j_garcia]

And you are using the LFE input on the sub? Have you tried FM stereo or another input to see if it is working? Also check the level setting for the sub in the speaker setup, to make sure it isn't turned down. Default is probably "0", with it going up and down from there. Does that receiver have other pre-outs? Try testing with one of the main L & R outs just to see if the sub gets sound. Which output from the receiver did you use? If there are two, try the other one.

 

[collegeaudio]

It has two subwoofer pre-outs, neither of which seem to be working. However, I just tested the 'Center' pre-out and it appears to be working. Both L/R main pre-outs were working when I was using the line-in connection.

Would a Y splitter connected to the L/R pre-outs combine the signal and send it through the coaxial cable?

I ran through all the levels settings, it was set at 0db and there was no change when I cycled through both negative and positive db.

 

[j_garcia]

No, both of those outputs are the same thing, so it shouldn't matter which you use and using both won't make any difference.

So you used the center out to the sub and the sub turned on? That means it is likely the receiver that has the problem, not the sub.

 

[collegeaudio]

I was hoping that wasn't the problem, but figured it probably was. My receiver desperately needs an upgrade.

Is there a temporary solution using pre-outs? I'm running speaker cable right now and need the channels.

 

[j_garcia]

Use the main L&R outs to the filtered inputs on the sub, set mains to Large and no sub, the rest to small. That is actually Polk's recommended setup for their own satellite speakers, but for a temp solution, it should work for you too.

 

[collegeaudio]

One last question. Is there any problem using the coax cable to connect the L or R channel to the corresponding filtered input and playing stereo and mono music? For stereo it should only be missing the other channel and for mono it should be theoretically normal... correct?

My roommate has a lot of mono music and this would hold him over for the next few days while I wait for the RCA cable I need.

 

[j_garcia]

Yes, that is correct.