So I have a Blu-ray Disc with Dolby Atmos I watched on a Samsung BD-J7500 passed thru to a Denon 4300H AVR. The Denon showed Dolby Atmos as the audio format without a problem. I then copied the blu-ray with MakeMKV onto an external hard drive. Next, I tried viewing the movie via Plex on the J7500 directed thru the 4300H. However, the audio format shown on the 4300H was not Dolby Atmos, but Dolby Digital + (LogoS) (the DD logo plus an S) That format is described in the 4300H manual as Dolby Digital+ with Dolby Surround, not Dolby Atmos. So I’m wondering what happened to the Atmos format. Is it being lost in the MakeMKV copy, the PLEX playback thru the J7600, or the 4300H interpretation? MakeMKV posts say it copies Atmos without any problems. Any thoughts?
Also, does the PLEX client specifically for Samsung Blurays support Atmos pass-thru?
Hello, when you use MakeMKV you don’t loose anything from the Blu-ray, because what you actually do is to “transfer” the information from one “container” (Blu-rays use TS or M2TS container) to the other (MKV container), so the video stream is transferred untouched, the same with the audio, so the Atmos information is untouched.
Also, in case you don’t know, Dolby Atmos is not a new audio codec, instead, it is a new encoding method that uses the already existing codecs: Dolby TrueHD for Blu-ray and Dolby Digital Plus for streaming services like Netflix. This means, for compatibility purposes, every Dolby Atmos stream include whether Dolby TrueHD or Dolby Digital Plus at its core.
Since you say that you used the same Samsung BD-J7500 with the Plex app installed, maybe The Plex server still doesn’t support pass-through for Dolby Atmos + TrueHD, that means the server is transcoding the TrueHD part into Dolby Digital Plus and that’s what you see in your receiver’s display.
I recommend you to test a Dolby Atmos with Dolby Digital Plus to see what happens, you can download it from here:
This is a 3D audio experience, where you can test different demos but you can download only the one on the right.
I have the same issue and I can confim this is a Plex problem.
I have a Dolby Atmos app on my Xbox One S. When I watch all movies demos, the AVR (setup a Pure Direct Stream) displays Dolby Atmos and I can hear all my speakers are used by the sound.
On the same Xbox One S, I run Plex and I watch a Dolby Atmos demo or a movies that contains Dolby Atmos track (Hans Zimmer Live in Prague for instance), the AVR displays Dolby Digital. and only 5.1 config is used.
So, same player (Xbox One S), same receiver (Pioneer VSX-LX302), two different results :
- Dolby Atmos 7.1 from the Dolby App for Xbox
- Dolby Digital 5.1 from Plex for Xbox
