A friend of mine recently got a new HDTV. It has an optical audio out port (the black square kind… Toslink or SPDIF, maybe?)
My question is: If he has an existing set of analog 5.1 PC speakers, is there any way to connect them to the TV while maintaining 5.1 surround sound? I THINK what I’m looking for is some sort of digital-to-analog converter, but I have zero experience with these things.
The speakers normally accept three 3.5mm" stereo minijack connections from a computer sound card (front left+right, rear left+right, center+subwoofer). The three cables from the sound card connect to the subwoofer unit, which then connects to the 5 speaker units using thin red & black cables.
Most audio equipment doesn’t have the audio inputs/outputs broken out the way your sound card does. I’m not aware of any simple devices that will convert from the optical output of the HDTV to something that your speakers can readily use.
I think your best bet will be to connect the A/V audio out connectors (#5 on your diagram) to the input of your computer sound card. You may need an adapter to go from the 2 RCA jacks to a mini-stereo plug, depending on what the line-in on your sound card will accept. The sound card can then take the dolby audio and distribute it to the appropriate speakers.
After looking at the users manual from the link for your speaker set, you should be able to connect the HDTV directly to the MP3/Aux jack on the control module for the speaker set (see # 6 on the speaker connection diagram). You will need an adapter cord to go from the red/white RCA connections on the back of the TV to the stereo mini-jack on the control module. You can pick one of these up at any Radio Shack or electronics store. Stay away from the over-priced “Monster Cables” that they will try to foist on you.
I would be very surprised if this did not properly decode the 5.1 stereo inputs from your TV signal.
