You got your new AV receiver because you wanted access to all the new formats. You’ve set up speakers all around your room and even some on the ceiling! Atmos here you come! But now you are noticing something weird. Your AV receiver isn’t displaying Dolby or DTS or even Atmos on the front. You are only getting Multi In. What the heck is Multi In and why is that all your AV receiver is getting? Let’s discuss!
Multi In is short for Multichannel PCM. Multichannel PCM essentially is when your source (DVD player, Blu-ray player, game console, PC, etc.) decodes the audio internally. Now your source is only sending out channel information. It is telling your AV receiver what sounds to play through which speakers (or channels).
Normally, you would bitstream the audio to your AV receiver. When you bitstream, you are sending the encoded soundtrack (again, normally in a DTS or Dolby format) to your AV receiver. Your AV receiver will do the decoding and then send the sounds to your speakers.
If the decoding is done at the AV receiver, it will display the format. You’ll see DTS Master Audio or Dolby Atmos on the front display (see above). If the decoding is done at the source, your receiver will have no idea what format the audio was originally encoded in as it didn’t do the decoding. It only has the channel information so your AV receiver will display Multi In. This lets you know that the source did the decoding.
What If You Don’t Want Mult In?
You didn’t buy this expensive AV receiver to see “Multi In” on the front panel! You want the receiver to do the decoding, not your source. Can you change this?
Some sources, like PCs, game consoles, and some streaming devices, force you to use Multichannel PCM with either all or some of the surround formats. Your best bet is to go into your menus and look for “Bitstream Audio” or “Let my receiver decode audio” settings. If you can’t find them, and a Google search doesn’t help, then your device may be incapable of sending out the encoded audio.
Does Multichannel PCM Sound Different
The decoders in your source and AV receiver are the same. If it can decode it, it will decode it properly. If you are getting Multi In on your AV receiver, the sound will be the same as if the receiver had done the decoding. The downside of having your source send out Multichannel PCM is that upmixing becomes more of an issue. Check out this article for more information.
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