A practical guide to TV audio formats: from stereo to Dolby Atmos without the jargon

Modern TVs and streaming apps offer a long list of audio formats, from simple stereo to Dolby Digital and Dolby Atmos. The names can look confusing, and it is not always obvious which settings actually improve what you hear at home.

This guide explains the most common TV audio formats in plain language and shows how to set them up so you get the best experience from your existing equipment, without chasing buzzwords in the menu.

What “channels” really mean on your TV

Most TV menus mention numbers like 2.0, 3.1 or 5.1. These numbers describe how many separate channels are in the audio track. The first number is the count of speakers around you, and the last “.1” is the low frequency effects channel for deep bass.

For example, 2.0 is traditional stereo, with left and right channels. 5.1 means left, center, right, two rear channels and one low frequency channel that usually feeds a subwoofer. Even if you do not own that many speakers, your TV or bar can mix these channels down to what you have.

Stereo: still the default for many setups

Stereo is a two channel format that almost every device supports. Broadcast TV, older consoles and many YouTube videos are still delivered in stereo. If your TV is connected directly to a basic pair of speakers or a simple bar without surround features, stereo is usually the most reliable option.

In the audio settings, this often appears as “PCM” or “2.0”. PCM sends an uncompressed signal, which is easy for any receiver or bar to understand. It is also a safe choice when you get silence or strange effects with more advanced options.

Dolby Digital and 5.1: the common surround baseline

Dolby Digital (often labeled AC-3 or just Dolby) is the standard compressed surround format used on many TV broadcasts, DVDs and some streaming services. A Dolby Digital 5.1 track can carry discrete rear and center channels in relatively little bandwidth.

If you own a true 5.1 home theater or a bar that supports 5.1 via HDMI ARC or optical, enabling Dolby Digital in your TV’s output settings can activate those extra channels for movies and sports. When your equipment does not support it, you may get downmixed stereo or no audio, so check your receiver or bar manual for supported formats.

DTS formats: when they matter and when they do not

Some discs and older media players use DTS formats instead of Dolby. Many modern TVs, bars and game consoles no longer prioritize DTS, especially in streaming apps, so support can be inconsistent. If your devices clearly list DTS capability, you can enable it in the TV settings to get full surround from compatible sources.

If not, selecting DTS may cause silence or a fallback to basic stereo. For most streaming-focused setups, it is simpler to stick with Dolby formats or PCM, since those are more widely used by current apps and TVs.

Dolby Atmos: what it really adds

Dolby Atmos is an object based format that can carry height information, such as a helicopter moving above you. Some Atmos systems use ceiling speakers, while many bars use up-firing drivers and processing to simulate height with reflected audio.

Not every stream with the Atmos logo will feel dramatic, and the benefit depends heavily on both the content and your room. To get Atmos from a TV app into a compatible bar or receiver, you usually need HDMI eARC and must set your TV’s audio output to “Auto” or “Passthrough” for Dolby formats, instead of forcing PCM stereo.

ARC vs eARC: why the HDMI port label matters

HDMI ARC lets your TV send audio back down a single HDMI cable to a bar or receiver. This is convenient, but standard ARC has limited bandwidth. It typically handles stereo PCM and compressed formats such as Dolby Digital and basic Atmos from streaming apps.

HDMI eARC increases bandwidth so the TV can output higher quality formats, including lossless surround and more robust Atmos tracks. If your TV and bar both support eARC, enable it so you can select the richer options in the TV’s audio menu, especially for streaming services that offer Atmos.

Pass-through vs PCM: which setting to pick

Many TVs present a choice between “PCM”, “Bitstream” or “Passthrough”. PCM means the TV decodes the audio and sends a simple uncompressed signal, often as stereo. This is ideal when your bar or receiver is basic, or when other formats cause compatibility issues.

Passthrough or Bitstream sends the original compressed format directly to the connected device, which then decodes it. Use this when your bar or receiver clearly supports Dolby Digital, Dolby Digital Plus or Dolby Atmos, and you want to retain full surround information from streaming apps or external players.

Simple setup tips for everyday viewing

If you feel lost in menus, a short checklist can help. First, connect your bar or receiver with HDMI ARC or eARC whenever possible, instead of optical, since HDMI usually supports more formats and better lip sync options.

Next, start with PCM to confirm everything works, then switch to Dolby Digital or “Auto” and test with a movie that specifically lists 5.1 or Atmos. Leave DTS and rare options off unless your hardware and media clearly require them.

When to change settings and when to leave them

You do not need to adjust audio formats for every show. Once you find a stable combination that works across live TV, games and streaming, leave it alone. Only revisit the menu if you buy a new bar, add a receiver or start watching content that you know supports Atmos.

The aim is not to enable every advanced format, but to match your TV settings to the capabilities of your connected equipment. With a few careful choices, you can avoid silent channels and enjoy a consistent, engaging experience from your existing system.