Soundbar ARC vs Optical: Which Connection?

What ARC and optical name on a listing

The two connection words you will meet on a soundbar listing are HDMI ARC and optical, sometimes written as digital optical. Both names describe how a TV sends audio to a soundbar, but they are different kinds of connections.

HDMI ARC stands for Audio Return Channel. It is a feature of the HDMI connection that lets audio travel from the TV back to the soundbar over the same cable. The newer version, eARC, is described by the HDMI specification overview as simplifying connectivity and providing greater ease of use while supporting the most advanced audio formats and highest audio quality.

Optical, also called Toslink, names a fiber optic audio port. It carries digital audio in one direction, from the TV to the soundbar, through a separate cable. On a listing, you will see HDMI ARC or eARC in the port section, and optical or digital optical next to it.

A soundbar title often reads "Soundbar with HDMI ARC" and lists the other ports in the bullet list below, or it names both connections side by side. The title is the first place to look, and the bullet list names the ports in full.

Audio formats each connection carries

The important difference between the two connections is how much audio they can carry. eARC, the newer version of ARC, is described by the HDMI specification as supporting the most advanced audio formats and highest audio quality. That is the connection a listing pairs with format words such as Dolby Atmos.

Optical has a lower bandwidth than an HDMI connection. It can carry compressed digital audio such as Dolby Digital, which is common on broadcast and streaming sources, but it cannot carry the lossless formats that a Dolby Atmos setup calls for. If you are choosing between the two, the format words on the listing tell you what the maker states the connection can carry. A listing that names only optical and no format words is a simpler pairing.

The optical input limitations article explains this in more detail.

When you read a listing, look at the connection words together with the channel layout and format words. A listing that names both HDMI eARC and Dolby Atmos pairs the connection with the format. A listing that names only optical and a 2.0 layout is a simpler setup. The audio codecs support article walks through how format words appear.

Ease of use with ARC, eARC and CEC

ARC is the easier connection to live with in most setups. It carries audio in both directions over one cable, so the soundbar plays audio from the TV's apps and from devices connected to the TV. The HDMI specification overview notes that eARC simplifies connectivity and provides greater ease of use.

ARC also pairs with HDMI CEC, a control feature that lets the TV remote adjust the soundbar's power and volume. The HDMI CEC explained article covers how CEC appears as a listing word. For a fuller comparison of the two ARC versions, see HDMI ARC vs eARC.

Optical is a one-way connection. You send the TV's audio to the soundbar through the optical cable, but the TV and soundbar are controlled separately unless the soundbar's listing names its own remote or an app. You may also need to change the TV's audio output setting when you switch between the TV's speakers and the soundbar. This is why optical setups often keep the TV remote and the soundbar remote both on the table.

Checking your TV's ports before buying

The right connection for your setup is the one your TV has. Look at the TV's listing or manual for its port names. An HDMI port on a recent TV is often labeled ARC or eARC, and many TVs also have an optical port labeled Digital Audio Out or Optical. An older TV may only have optical, and a budget TV may have neither.

If your TV has an ARC-labeled HDMI port, choose a soundbar whose listing names HDMI ARC or eARC. If your TV has only optical, choose a soundbar whose listing names an optical input. If your TV has both, ARC is the connection to build the setup around, and optical can be a backup.

The connectivity options article reviews all the connection words you will find on a listing, from HDMI to Bluetooth.

If you want to compare soundbars by their stated connection details, the best HDMI ARC soundbars guide is the place to start.

What this site cannot say

This article explains what the two connection words mean and how to read them on a listing. It cannot tell you which connection makes a particular TV and soundbar work together, which audio format a given TV sends over ARC or optical, or that one connection is a better match for your room. Those questions are answered by the TV's manual and the soundbar's maker page.

The connection you choose does not change the channel layout of a soundbar. A 2.0 bar and a 5.1 bar each state their layout in the title; the connection word names how the audio gets to the bar. The soundbar channels explained article covers the layout words.

What to pick for your situation

Questions

What does ARC mean on a soundbar listing?

ARC stands for Audio Return Channel. It is a feature of an HDMI port that lets audio travel from the TV back to the soundbar over the same cable, so the soundbar can play audio from the TV's apps and connected devices.

What does optical mean on a soundbar listing?

Optical, also called Toslink, names a fiber optic audio port that carries digital audio in one direction from a TV or another source to the soundbar.

Which connection supports more audio formats?

eARC, the newer version of ARC, is described by the HDMI specification as supporting the most advanced audio formats and highest audio quality. Optical carries compressed digital audio but has a lower bandwidth.

Can I use both ARC and optical at the same time?

A soundbar may list both ports, but the TV sends one audio signal at a time. You would choose one connection in the TV's audio settings. Read the soundbar listing and the TV manual for the switching steps.

Does ARC work with any HDMI cable?

ARC works over an HDMI connection. Read the soundbar's listing for what the maker includes in the box. If a cable is not included, check the maker's page for the recommended cable type.

Does optical carry multi-channel audio?

Optical carries compressed digital audio formats such as Dolby Digital, which can include multi-channel content. It does not carry the lossless formats that eARC supports. Read the listing and the maker's page for what a given soundbar's optical input accepts.

Is optical still worth using?

Optical is the connection to fall back on when a TV has no HDMI ARC port. It carries compressed digital audio and is a common port on older TVs and budget soundbars.