Setting up a home audio system can be confusing if you're not sure what each port on your devices does. Many ports have multiple names or look similar, but they serve different purposes. This guide will help you identify the most common home audio ports and understand what they’re used for.
Optical (Toslink) Port
Also called: Digital Optical, SPDIF, Optical Audio
What it looks like: A small square port with a flap or red light inside
Used for: Sending digital audio from a TV, game console, or Blu-ray player to a soundbar or AV receiver
Cable type: Toslink (optical audio cable)
HDMI ARC / eARC Port
Also called: HDMI Audio Return Channel, Enhanced Audio Return Channel
What it looks like: A standard HDMI port labeled “ARC” or “eARC”
Used for: Sending audio from your TV back to a soundbar or receiver using the same HDMI cable that carries video
Cable type: HDMI High-Speed or Ultra High-Speed cable
3.5mm Audio Jack
Also called: Aux, Headphone Jack, Line In, Line Out, Line Level
What it looks like: A small round port, usually green, black, or blue
Used for: Connecting headphones, portable speakers, or sending and receiving analog audio between devices like phones, computers, and stereos
Cable type: 3.5mm stereo cable
RCA Ports
Also called: Analog Audio, Red and White Audio
What it looks like: Two round ports, usually red and white
Used for: Sending stereo analog audio between devices like CD players, TVs, and amplifiers
Cable type: RCA stereo cable
Coaxial Digital Audio Port
Also called: Digital Coax, SPDIF Coax
What it looks like: A single round port, usually orange
Used for: Sending digital audio using an RCA-style cable
Cable type: Coaxial digital audio cable
Speaker Terminals
Also called: Binding Posts, Spring Clips
What it looks like: Red and black terminals or clips
Used for: Connecting speaker wire from an amplifier or receiver to passive speakers
Cable type: Bare speaker wire or banana plugs
USB Audio Port
Also called: USB Audio, USB Input
What it looks like: A standard USB-A or USB-C port
Used for: Connecting a computer, streaming device, or media player to a speaker, soundbar, or receiver that supports USB audio
Cable type: USB cable (type depends on the device)
Quick Tips
- Match the port label on your device to the cable type you’re using
- Don’t force a cable into a port that doesn’t fit easily
- If your device has multiple audio outputs, choose the one that matches your speaker or receiver’s input
Need Help?
Monoprice offers a wide range of cables and adapters for every type of home audio connection. If you're unsure which cable or port to use, our support team is happy to help.