Not enough people know this about home theater passthrough

Formats can wreak havoc with a home theater system. Generally speaking, streaming services, studios, and many device makers do what they can to make sure media plays in the best available format. But home theaters are often Frankensteinian creations borrowing parts from multiple brands and years, and all it takes is one component being outdated or otherwise lacking format support for you to be left with disappointing results.

The solution to this — in some situations, anyway — is something known as passthrough. For those unfamiliar, I’m going to explain the basics. But even if you know something about it, there are limitations that you need to be aware of, particularly if you’re into console or PC gaming. Typically, gaming is so dependent on high-performance specs that your system is better off if it’s armed for the latest standards from the start. Passthrough is best used with movies and TV shows.

What is passthrough, and what does it solve?

Check for these options on your devices

One of my biggest gripes with TV makers is how stingy many of them are with format support. Usually I’m concerned with HDMI bottlenecking (more on that in a moment), but you’ll also run into issues with which formats are supported in the first place, and how well they’re handled. Many TVs can’t decode DTS:X, for example. It could be that your TV doesn’t support spatial audio formats at all, or that connected speakers and/or receiver will do a better job of decoding whatever it is you want to play. If you let your TV try to decode a mix before it heads out, you could end up stuck with a lesser format (such as “plain” 5.1-channel surround sound) or simply inaccurate handling of an available option like Dolby Atmos.

Quiz

8 Questions · Test Your Knowledge

Home theater systems
Trivia challenge

From surround sound to 4K projectors — how well do you really know your home cinema setup?

AudioDisplayFormatsHardwareHistory

Begin

What does the ‘1’ refer to in a 5.1 surround sound system?

AA single front center speakerBA low-frequency effects (subwoofer) channelCA rear surround channelDA height speaker channel

Correct! The ‘.1’ in any surround sound configuration refers to a dedicated low-frequency effects (LFE) channel, which is typically handled by a subwoofer. This channel carries bass-heavy sounds like explosions and deep musical tones, adding physical impact to your listening experience.

Not quite. The ‘.1’ refers to the dedicated low-frequency effects (LFE) channel, handled by a subwoofer. The ‘5’ counts the full-range speakers — typically front left, front right, center, and two surrounds — while the subwoofer handles the deep bass on its own separate channel.

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What is the native resolution of a Full HD (1080p) display?

A1920 x 1080 pixelsB2048 x 1080 pixelsC1280 x 720 pixelsD3840 x 2160 pixels

Correct! Full HD, commonly known as 1080p, has a native resolution of 1920 x 1080 pixels. It became the standard for HDTVs in the mid-2000s and remains widely used today, even as 4K (3840 x 2160) becomes more mainstream in home theater setups.

Not quite. Full HD (1080p) has a resolution of 1920 x 1080 pixels. You might be thinking of 2K cinema (2048 x 1080), which is slightly wider, or 4K (3840 x 2160), which is four times the resolution of 1080p and increasingly common in modern home theater displays.

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Which audio format was developed by Dolby Laboratories and introduced with Blu-ray as a lossless surround sound option?

ADolby DigitalBDolby Pro Logic IICDolby TrueHDDDolby Digital Plus

Correct! Dolby TrueHD is a lossless audio codec introduced alongside the Blu-ray format, capable of carrying up to 14 discrete audio channels. It is the codec underlying Dolby Atmos on Blu-ray discs and delivers studio-master-quality sound to home theater enthusiasts.

Not quite. The answer is Dolby TrueHD, a lossless codec introduced with Blu-ray that can carry up to 14 channels of audio at full master-quality fidelity. Dolby Digital is an older lossy format from the DVD era, while Dolby Digital Plus is an enhanced but still lossy codec used for streaming services.

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What is the primary function of an AV receiver in a home theater system?

ATo upscale video content to 4K resolutionBTo decode audio signals and amplify them to connected speakersCTo store and manage a library of digital media filesDTo convert HDMI signals into optical audio output

Correct! An AV receiver is the hub of a home theater system, responsible for decoding audio formats like Dolby Atmos and DTS:X, then amplifying those signals to power connected speakers. It also handles video switching, allowing multiple source devices to route through a single HDMI connection to your display.

Not quite. An AV receiver’s primary role is to decode multi-channel audio formats and amplify the signal to drive your speakers. While many modern receivers include video processing features like upscaling, their core purpose has always been audio decoding and amplification — making them essential for true surround sound setups.

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In what decade was Dolby Surround — the first consumer surround sound format — introduced to home video?

A1970sB1980sC1990sD2000s

Correct! Dolby Surround made its way into home video in the 1980s, first appearing on VHS and LaserDisc releases. It was a matrix-encoded format derived from Dolby Stereo used in cinemas, and it laid the groundwork for the more sophisticated discrete surround sound formats that followed in the 1990s.

Not quite. Dolby Surround arrived in homes during the 1980s, encoded into VHS tapes and LaserDiscs. While the technology had cinema roots in the 1970s, it wasn’t until the 1980s that consumer home video hardware began to support it, kicking off the era of home theater surround sound.

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What does HDR stand for in the context of modern home theater displays?

AHigh Definition ResolutionBHybrid Display RenderingCHigh Dynamic RangeDHorizontal Detail Ratio

Correct! HDR stands for High Dynamic Range, and it refers to a display’s ability to reproduce a wider range of brightness levels — from deep blacks to very bright highlights — as well as a broader color gamut. Formats like HDR10, Dolby Vision, and HLG are all HDR standards used in home theater TVs and projectors.

Not quite. HDR stands for High Dynamic Range. It’s a display technology that dramatically expands the contrast ratio and color range of a picture, making bright highlights more dazzling and shadows more detailed. Common HDR standards you’ll see on home theater equipment include HDR10, Dolby Vision, and HDR10+.

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Dolby Atmos introduced a fundamentally new concept to surround sound mixing. What was it?

ALossless compression of stereo audio tracksBObject-based audio that places sounds in three-dimensional spaceCWireless transmission of surround sound signalsDAutomatic speaker calibration using a microphone

Correct! Dolby Atmos revolutionized surround sound by introducing object-based audio. Instead of assigning sounds to fixed speaker channels, sound designers can place audio objects anywhere in a three-dimensional space, including overhead. The system then renders those objects dynamically based on whatever speaker configuration you have at home.

Not quite. Dolby Atmos introduced object-based audio, which was a major departure from traditional channel-based surround sound. Rather than mixing sounds into set channels like ‘left surround’ or ‘center’, mixers place audio objects in 3D space and the Atmos renderer figures out the best way to reproduce them through your specific speaker layout, including height channels.

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Which physical disc format won the high-definition home video format war in 2008, defeating its main rival?

AHD DVDBBlu-rayCUMDDDVD-HD

Correct! Blu-ray, backed by Sony and a broad coalition of studios and manufacturers, defeated HD DVD — championed primarily by Toshiba and Microsoft — in early 2008. The turning point came when Warner Bros. announced it would go Blu-ray exclusive, prompting several major retailers and studios to follow suit, effectively ending the format war.

Not quite. Blu-ray won the high-definition format war in 2008. The conflict between Blu-ray and HD DVD had raged for roughly two years, but Warner Bros.’ decision to go exclusively Blu-ray in January 2008 proved decisive. Toshiba officially discontinued HD DVD shortly after, leaving Blu-ray as the standard for high-definition physical media.

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Passthrough (sometimes labeled bitstream) is meant to solve this situation, not just on TVs, but on equipment like media streamers, Blu-ray players, and game consoles as well. Devices that support it attempt to pass along data without processing, saving that job for a receiver or soundbar. With DTS:X, passthrough might be a way around the missing compatibility I talked about. Similarly, if you’ve got an Atmos-capable receiver, it can potentially handle channel metadata better than your TV, which may result in noticeable differences in the final output.

I’m focusing on audio here, but there is such a thing as video passthrough as well. Mainly I’m thinking of 4:4:4 chroma passthrough, which you may want enabled if you’re connecting a PC or console and want better color representation, albeit possibly at the expense of things like refresh rates. I’m not going to touch on video passthrough much in this article, since its use cases tend to be more niche.

There are some key limitations on passthrough support, the most obvious being that the output device still needs to understand the format you’re working with. If your Blu-ray player and an inserted disc support DTS:X, but your soundbar or receiver doesn’t, the whole endeavor is pointless. Likewise, you can’t pass through VRR (variable refresh rate) graphics to a TV that’s locked at 60Hz.

Perhaps the most significant barrier is HDMI compatibility. It’s not about specific format support — different HDMI specs simply have more bandwidth available, so if a format consumes data beyond a port or cable’s capacity, it won’t matter what your input or output devices are ready for. You can’t force lossless Dolby Atmos or DTS:X through an HDMI 2.0 ARC connection. If your TV doesn’t have an HDMI 2.1 port with eARC, which offers a 48Gbps (gigabits per second) pipe, you’ll have to revert to one compressed audio standard or another. You can get compressed Atmos over ARC, in case you’re wondering, and that’s not such a big deal given that most streaming services rely on it.

Be sure to check devices not just for general HDMI specs, but their specific HDMI passthrough functions. If you want lossless Atmos, you’ll have to guarantee that HDMI 2.1 passthrough is available.

How do you enable passthrough?

Options on TVs, consoles, and other gear

On a TV or add-on media streamer, this is going to depend on the exact software platform it’s based on, and which formats you want to flow through. Roku devices, for instance, may ask you to go to Settings -> Audio -> S/PDIF and ARC to toggle one form of passthrough, and Settings -> Audio -> Digital output format for another. On Google TV devices, you may be able to head over to Settings -> Display & Sound -> Advanced sound settings -> Surround sound mode and select Passthrough.

Notice that the word “may” has popped up twice, owing to both hardware compatibility and the possibility that you may be on a different OS version. With Google-based devices, there’s the additional issue of companies casually relabeling menus and options. Things can get confusing. When in doubt, you’ll want to refer to manuals or web instructions, particularly for soundbars, receivers, or dedicated Blu-ray players.

Speaking of labeling, as I mentioned earlier, passthrough is sometimes marked as bitstream. Technically, there is a difference, but only in that bitstream is the “what” and passthrough is the “how.” Keep this in mind for all platforms and devices.

Case in point: two of the leading game consoles, the Sony PlayStation 5 and Microsoft’s Xbox Series X. On a PS5, you have to head over to Settings -> Sound -> Audio Output and flip Audio Format (Priority) to Bitstream (Dolby) or Bitstream (DTS). The Xbox equivalent of this involves navigating to Settings -> General -> Volume & audio output, setting HDMI audio to Bitstream out, and picking Dolby Atmos or DTS:X under Bitstream format. If that’s not awkward enough, expect to change additional settings to get this to work for Blu-ray discs, possibly in the middle of playback.

The situation gets even more complicated if you’re connecting a Mac or Windows PC. Windows 11 requires you to launch mmsys.cpl from the search bar and check Allow applications to take exclusive control of this device under an HDMI output’s Properties -> Advanced right-click menu, then set your Windows sound to stereo to deliver raw output. Once that’s done, you may still need to make sure the apps you’re using (like Plex or VLC) are set for passthrough if they support it.

As for video passthrough, there’s not usually much that has to be done on computers, but you will need to explore HDMI-related options on TVs and other devices to see if anything is applicable. For features like VRR or 4:4:4 chroma, you’ll also want to check if they’re enabled on an input device — they may not be active by default.

4K Capability

Yes

What’s Included

PlayStation 5 Digital Edition, Dualsense Wireless Controller, 2 Horizontal stand feetm HDMI cable, USB cable

Brand

PlayStation

Storage

1TB SSD