Speaker-out to RCA-in Question

[threeeyedtoad]

I've poked around a bit on these forums to try to find an answer to my question, but have not yet found one.

I've recently acquired a receiver capable of 5.1 output. I have four speakers + a sub, which I have hooked up (typical installation). However, my question is in regards to the center channel.

I would like to use the speakers built-in to my television as a the center channel. The speakers are normally driven by line-level inputs via RCA connections (two of them, one for left and one for right). However, I would like to use the speaker terminals out of my receiver to drive the speakers in my television. (The impedance is rated 8 to 16 Ohms, if that matters...)

Here's my theory: I want to take a standard pair of stereo RCA cables, cut and strip down to bare wires for each left and right at one end, and then attach those wires to the center speaker terminals on my receiver. I would expect that left AND right positive (is that the inner or outer wire of an RCA cable?) would get attached to the positive (red) terminal, and then left AND right negative would get attached to the negative (black) terminal. I'm hoping that way, I'll get sound to both speakers.

So, in this communities' opinion... how bad an idea is this?

Thanks for the feedback/insight.

 

[Adam]

3-eye, first...welcome to the forum!

Second, don't do that! The speaker outputs on your receiver are much higher power than the RCA-style line-level signals that your TV is expecting.

We can help you get that set-up, I'm sure. My question for you is...does your receiver have pre-outs on it, especially for the center channel? That's what you'd want to use.

Adam

 

[Adam]

Oh, another question. Does your TV allow you to use the speakers as a center channel independent of the video source?

 

[threeeyedtoad]

Answers as best as I am aware:

1. The receiver we're talking about is an old Sony STR-DE675. It's on it's last legs (I believe there is a short in the rear speaker circuit that causes me endless frustration), but when it works, it does the job. Unfortunately, it has no pre-amp outs.

akamaipix.crutchfield.com/Manuals/158/158STRE575.PDF

2. I'm not sure if I can select video sources independently of audio sources. Why is that relevant?

So, is there some way of cutting the speaker level down to line level, preferably for cheap?

Thanks for the quick feedback!

 

[Adam]

Answers as best as I am aware:
2. I'm not sure if I can select video sources independently of audio sources. Why is that relevant?

It depends on how you use your TV. If you only use it as a monitor (so, don't use the built-in tuner), then it doesn't matter because you will always have it set up to use those RCA inputs. If you do use the built-in tuner to watch TV, then it won't use those RCA inputs for the sound (instead, it will play whatever sound is there for the show that you're watching) - unless you can set it up to use those RCA inputs regardless of what you're watching.

So, is there some way of cutting the speaker level down to line level, preferably for cheap?

Not that I know of, but I'll let some more experienced people jump in on this one.

If your receiver can do it, you might want to just (for now) set it up to run a phantom center channel. Perhaps that's what you have it doing right now. Have you considered getting a seperate center channel? For quite some time, I wanted to be able to use my TV speakers for the center channel because it seemed so convenient and less expensive, but I'm quite glad that I got a good center channel because I'll bet that it sounds a lot better than the TV speakers would have.

 

[threeeyedtoad]

Adam,

Thanks for the quick feedback. I see why you were asking about the TV inputs now. Yes, I'm just planning on using the TV as a monitor -- all audio and video switching will be handled by the receiver.

I poked around a bit, and found several "line level converters" around the interwebs. (Don't know why it didn't occur to me to run that search sooner...) It seems they are a common item for car audio enthusiasts. Looks like the part will run me about $20.

Thanks again for the prompt response(s), and for the words of caution. Probably saved me blowing out the speakers on my TV.

Now I just need to solve that short in the rear speakers circuit...

 

[Adam]

I poked around a bit, and found several "line level converters" around the interwebs. (Don't know why it didn't occur to me to run that search sooner...) It seems they are a common item for car audio enthusiasts. Looks like the part will run me about $20.

Hey, thanks for the info! I never knew that those existed. Great stuff.

Good luck with getting your system set-up the way that you want, and with that short!

 

[j_garcia]

Yes a line level converter will work, but it still isn't the best idea because the TV speakers aren't going to match with the rest of your speakers. At the very least, I recommend having the front 3 speakers matching because they play the vast majority of your sound for movies.