You can either connect the sources directly to the TV if you have a soundbar with one HDMI input, or if you have a receiver with multiple HDMI slots, you can connect all your sources to that instead. Here are a couple of examples of home entertainment setups that take advantage of a TV's audio passthrough. It also means you can connect sources directly to the TV for the best video experience, while the TV passes on the audio duties to the receiver. In short, passthrough is just an option that allows you to get surround sound for multiple source devices with fewer cables.
A 5.1 setup is one of the different configurations you can have, and it's used more with Dolby Digital and DTS signals, while newer formats like Dolby Atmos and DTS:X use more speakers, like 7.1, 5.1.4, etc. You can see that two cables are going to the TV - one for the video and one for the audio. This image is an example of a 5.1 surround sound setup with a TV that doesn’t support passthrough. You can still get the same audio-video experience without passthrough, but you'll have more wires going to and from your TV. Passthrough isn’t a necessity, and it's only important if you have a surround sound setup or a dedicated soundbar. If you use the TV’s speakers, you don’t need to worry about passthrough because sound is played from the TV directly. At least one source device capable of outputting an audio signal.A speaker system with an HDMI ARC or Digital Optical output.Passthrough is only helpful when you have the following: It's important to have a TV that supports passthrough if you watch movies with these audio formats, like Blu-rays that tend to have DTS:X audio.
Most TVs support some sort of audio passthrough over ARC and Digital Optical connections, while more TVs are starting to come out with eARC support for lossless Dolby Atmos and DTS:X signals. Some TVs can only pass audio when it's in a certain format (DTS or Dolby), while others can pass both audio formats.