Entertainment Center: TVs, Stereos, VCRs and DVDs - Panasonic plasma TV - problem with audio

I have a new plasma flat screen that I have connected to a Sony home theater system. A problem I am having, most noticable while watching movies on the cable companies premium movie channels, is that it is difficult to hear the actors' dialog. In order to make it audible, I have to turn up volume to the point where the backround music (and other sound effects) is too loud.

To provide a little more information, my home theater system is an older, inexpensive, system that does not have connections for optical/digital cable. As a result, I've had to connect it to the TV with RCA cables. I mention this because I've wondered if this might be the root of my problem since with this set-up I don't seem to get any audio on the center speaker. Am I possibly only getting the dialog on the side and rear speakers, in which case the solution probably would be to upgrade the home theater system so that I can connect with optical or digital cable?

Am I on the right track here, or does anyone have any other suggestions? I have not found any audio adjustment on either the TV, cable box, or receiver that remedies the problem, but would love to know if there is anything I can try short of upgrading the system.

Thanks.

Without more detail it's difficult to say where the problem lies but the lack of center speaker sound is a good clue. Don't think it has anything to do with your cables.
I assume your home theater system has a Dolby Digital 5.1 decoder; is this selected or is your system trying to produce center channel sound through one of the "sound field" settings?

I just re-read your post. If you are connected through the RCA connectors then there is no center channel info going to the home theater system. So there will be no sound on the center channel. However the stereo sound should still be OK, the balance between speech and background should be normal. But you need to select regular Dolby stereo on your home theater.
If you want center channel you will have to upgrade to a 5.1 decoder (and optical/digital connections) but there is no reason your current setup can't give perfectly adequate stereo, you should not be having this problem.

While it is true you cannot pass a dolby digital or DTS signal over stereo RCA cables, you can still get surround sound. Dolby pro logic is a 4 channel surround format (left, right, center, surround) that can be passed over stereo RCA cables. Most receivers also have built in simulated surround sound modes that work on any type of input signal (stereo, pro logic, etc.)

If the stereo is receiving a surround format and you are getting no sound from the center channel speaker, that is your problem. The majority of dialog is sent to the center channel so if that is not working correctly that is why you are not hearing the dialog. Is the center channel speaker working correctly with other sources? (radio, cd, dvd, etc.) If it is working, check the audio output settings on the TV (bass, treble, fixed / variable volume, surround mode, etc.) Also check the setting on the stereo. (surround mode, center channel level, bass, treble) If the center channel does not work with any source, check the speaker cables / connections. Also check the RCA connections to make sure they are no loose.

-Mike
"I just said we'd make it across. I didn't say anything about the wheels staying on."

For my setup, I find the built in simulated surround mode on my receiver provides the best sound when watching non Dobly Digital cable channels.

KenB: The Audio is coming from a cable box so the choice is almost certainly either 5.1 over optical/digital or regular Stereo over RCA, not Pro Logic. The Home Theater system apparently does not have a 5.1 decoder. So logically you should just get regular stereo out of the front right and left speakers only, but the voice-to-background ratio should be OK. If the system has simulated surround sound capability, you should get output on all the speakers. Are you using a simulated surround setting? And are you getting output on the rear speakers? So anyway, as Mike says, the absence of decent level dialog out of the right/left speakers indicates that the system is in a mode that creates a center channel output but there is a problem in either the Home Theater system, the connections, the cable or the speaker itself that is preventing the center channel from working.

Ironhead has accurately described pro-logic.

My experience with cable was similar to Texasbrit's experience. I had to upgrade to digital cable to get any kind of surround sound and then it was only 5.1 and that was only if the premium channel broadcast in 5.1.
Switched to satellite and now have digital sound on ALL channels. If its not 5.1, I still get pro-logic, even on the so-called analog channels.