I have a new lg 42LB5800 Tv and an outdated JVC speaker system. For my last plasma tv, I was able to connect the red and white RCA cables to get audio from the tv to play on the JVC home theater system but now I cant figure out how to set it up.
In other words,
Is there any way for me to connect my old jvc home theater system to my lg smart tv with RCA AV cables while using the HDMI for video?
Yes, but if you do this person will not be able to utilize true digital sound which is the purpose of having a home theatre system. If you connect it via the analog rca jacks u will only have at best stereo left and right sound. You will have the power to the speakers via the amplifier from the home theatre system but the quality sound will lack as one would not like when playing a bluray move ...in dolby digital 5.1 for example. ....this ties with the use of HDMI .....this output uses both DIGITAL AUDIO AND DIGITAL VIDEO only....like I said you can use the old theatre system but will only get left and righ using the rca jacks...you cant plug hdmi into this old theatre system but you can get true digital video if you connect the hdmi from the tv to a satellite reciever or bluray player u just wont get digital sound from the old reciever. but will get the power to left and right speakers in theatre system or you can get sound from all 54 speakers if you use dolby prologic instead of dolby digital on the amp settings if it has them....this does get a little confusing and also defeats the purpose in my opinion but you can hook it up ...
The only Audio output you have on the LG 42LB5800 is the Optical Digital Output so if your JVC speaker system does not have an Optical Digital Input on it, you will not be able to connect directly to the TV. What you might want to explore is if your set top cable box has an RCA (Red/White) Audio Output on it then you can just connect from that to your JVC speaker system because whenever you watch TV, the audio for those channels goes directly from your set top box to the JVC speaker system. If your set top box does not have RCA Audio outputs then you may want to look for a converter box that allows you to connect to the Optical Digital output on the TV into the Optical Digital Input of the converter box where a digital to analog converter (DAC) converts the signal and outputs to the analog ports that you can connect your JVC speaker system. Make sure that the DAC comverter you get is not just a Digital Coax to RCA. BHPhoto carries the Gefen EXT-DDIGAUD-2-AAUD GefenTV Digital Audio to Analog Adapter but there may be less expensive alternatives available from other retailers.^IV
Here is my basic set up RCA RT2906 receiver with HDMI connected to the tv via hdmi and a Kenwood VR-407 with A and B speakers connected to the tv via optical cable. I Connect my hdmi devices into the RCA and my stereo devices into the old Kenwood. The RCA gets 5 speakers and a subwoofer and the kenwood gets front speakers only in both A and B speaker ports. The RCA Does a decent job with video music and background affects but a really croupy job with speech and talking so I turn the RCA to my preferd volume and then with A and B speakers turned on I turn the Kenwood up to acomidate for the speach impediment of the RCA. It's cheap but it works on the cheap. My advice is if you have any money left after buying that nice tv spend a little more to upgrade the rest of your system to bluray and hdmi but if that's not an option then there are always ways to get around it for not a lot of money.