I think You want to play audio files from a hard disk.
You do need a device (called a High Definition Media Player, HD Media Player, or a HDMP) to do that. It will also connect to a TV, so You can see what You are asking it to do via the included remote control.
eBay has hundreds of them.
You will need to decide what kind of display You want (VGA, HDMI, etc.) and read the description carefully to make sure that one comes with a SPDIF (optical audio) output.
An eGreat R300 would work; I have one, but they are expensive.