Old stereos produce audio with analogue technology, unlike the digital format employed by High Definition Television (HDTV). Even though a new HDTV uses different types of ports for the digital connections, many HDTV sets are also backwards-compatible with analogue audio devices and are equipped with RCA-type jacks for connecting older equipment. This makes it possible to run the audio signal from an HDTV through an older system to use the speakers connected to the stereo.
Unplug the stereo and TV from the electrical socket while hooking the two components together.
Connect the white plug on the stereo cable to a left-audio input jack on the back of the stereo receiver or amplifier, then push in the red plug to the right-audio input. Most components have several input jacks, so locate any unused pair of inputs for the connection, such as a second tape deck input.
Insert the white plug on the other end of the stereo cable into the matching white analogue audio out jack on the rear of the HDTV.
Plug in the stereo and HDTV to the electrical socket and turn on the equipment.
Shut off the built-in speakers, if desired, by accessing the audio functions onm the HDTV. This may vary among different models, but typically involves pressing a "Menu" or "Display" button, then pressing the down arrow key to scroll through various video and audio options to reach "Speakers." On many TV sets, highlight "Speakers" with the down arrow key, then press the left or right arrow keys to turn off the built in speakers. Press the left or rigth arrow key once more to highlight the "On" setting to reactivate the built-in speakers.
Set the stereo selector knob on the front of the amplifier or receiver to the jacks that connect it to the HDTV.
Connect the stereo cable between the HDTV and older stereo before plugging in or powering on the electricity.