First Class Support for “Surround” Music

Feature Suggestions
1

Short Version

  1. Recognize that there is a lot of music available in 5.1 and 5.0, and make an effort to play it back correctly wherever possible. (My idea of “correct” is every channel going to its intended speaker. Small losses in quality due to transcoding are going to be unavoidable in some cases.)
  2. Document what works and doesn’t work with various clients. For clients that do support surround music, list the necessary client and server settings.

Obviously, there is some limited support for this now (details below), but it seems like an afterthought and I could find no official documentation on the subject. At the very least, as a first step, provide some documentation.

Details

Personally, I have an Apple TV (4th generation) and a PlayStation 4 hooked to my receiver. I prefer to use the Apple TV since it has no fan noise and uses the least amount of power, but I’d have to use the PS4 for the DVD version anyway, so I could live with that (if it worked).

I’ve tried every combination of surround format and Plex client available to me. Here’s what I found.

Apple TV

  • DTS in a movie container from a movie library is transcoded to AC3 and plays correctly
  • Everything in a music library (DTS, AC3, LPCM) is transcoded to stereo MP3, but is audible

I don’t think there’s any technical limitation causing this, based on the way movies are handled. It would be great if 5.1 formats in a music library received the same treatment as 5.1 audio tracks attached to movies.

PlayStation 4 (version 01.17)

The PlayStation app is maddeningly close to functional.

  • LPCM: Plays correctly
  • DTS 5.0: The progress bar moves as if the track is playing, but there’s no sound
  • DTS 5.1: Plays correctly, but the last 5-6 seconds of every track are dropped
  • AC3: Plays correctly, but the last 1-3 seconds of every track are dropped

For what it’s worth, VLC seems to (sometimes) get confused about the length of DTS tracks too, so it could be some underlying library they both use.

Plex Media Player Preview (version 1.0.3.132-16fa0ecc)

On a Retina MacBook Pro using HDMI out…

Mostly good news here. All surround formats appear to play correctly all the way to the end of the track, but a fraction of a second is dropped from the beginning (at least with DTS). This causes quite a few songs to start abruptly.

Having said that, I have no intention of adding a full blown computer to my living room on top of everything else.

This being one of the newer clients, maybe this indicates the future direction for all platforms, and maybe the improved surround support was intentional. But I doubt a direct port of this player will ever be possible on some hardware, so special attention to get surround music working on more clients might be necessary.

Thanks.

2

Yes! Surround Sound support is a must have in a media player that lives in the living room, hooked up to powerful audio equipment! +1000

3

Currently have my surround sound albums as mkv files and marked as movies (Windows Plex server running in the basement, going to my Roku, and into my AV system). The surround seems to work appropriately. But, the surround aspect of flac files do not appear to be supported at all (had to re-encode a few files after discovering this), and the library management is all off, since they get identified as any movie that happens to fit the bill. Reset agent to Personal Media, and it seems ok (a few remnants of the previous identification hanging around).

In truth, if there was a publicly accessible online db of surround albums that Plex could sync to, it would probably be pretty good.

4

and the library management is all off, since they get identified as any movie that happens to fit the bill.

Which is why it’s better to split it into separate tracks (discarding the video) and add them to a music library instead. The music matching all works.

Of course, anything that’s released on a commercial DVD should be matched in a movie library, so people could keep them as “movies” if they prefer. If that’s what you’re after, see https://forums.plex.tv/discussion/201846/feature-surround-music-library-for-5-1-mixes-ripped-as-video-files

5

@Vic333 said:
The surround seems to work appropriately. But, the surround aspect of flac files do not appear to be supported at all

Since music albums are not movies, the misidentification is expected if you search for music albums in movie databases.

That being said:
Surround music works quite well already in PMP.
(Other clients get stereo as I wrote above. More clients may learn to deal with surround music over time.)

I’ve successfully tested (even remotely):

  • FLAC multichannel
  • FLAC Hi-Res (192kHz/24 bit) stereo + multichannel
  • DTS/96 ‘naked’ files
  • MKA files

All added into a ‘Music’ library, of course.

6

I’ve added my multichannel wav and flac files into the music library but not had much success…on a Nvidia Shield TV (android)

If I play flac or wav multichannel files I get a long pause before it plays them in PCM 5.1 or stereo. Needs to be passthrough :slight_smile:

7

@JusNoGood said:
If I play flac or wav multichannel files I get a long pause before it plays them in PCM 5.1 or stereo. Needs to be passthrough :slight_smile:

Whether you are sending a FLAC file to the receiver (if it can decode it at all) or a PCM stream, is the same. The sound samples are identical.

8

My wavs that contain a DTS-CD 5.1 stream is being converted by Plex into stereo…so no not identical.

Yes my AVR can do flac. Currently Plex is converting my lossless flac 5.1 to PCM 5.1…I’d prefer it if Plex did passthrough and let my AVR do the work…same as what Plex is now doing with DTS-HD MA in the latest release of PMC for Android.

No point having an expensive AVR and then having a cheap Shield doing my decoding.

9

@JusNoGood said:
My wavs that contain a DTS-CD 5.1 stream is being converted by Plex into stereo…so no not identical.

WAV was never spec’ed to contain a dts stream. So I’d say it is somehow understandable that Plex doesn’t get it right.
Either extract the naked DTS stream from the WAVs or put them into .MKA containers.

No point having an expensive AVR and then having a cheap Shield doing my decoding.

It is digital data. A 1 will stay a 1 and a 0 stays a 0 - unless there is a sample rate conversion involved, which I cannot rule out. I don’t know the Android client that well.

10

VLC and other players can quite easily tell the codec in the file…I can open these files in VLC and see they are DTS-CD 3F2R, my amp can also tell a DTS-CD is coming its way and deal with it. I’m sure Plex could if it is programmed to do so.

If PCM was available from source then that could be the better one to go for (could)…but thats not what we are talking about here Plex is converting a HD stream into a generic PCM that any amp can then understand - I’d prefer my expensive AVR built specifically to get a HD feed and convert it directly to analog. In a similar way I want my plasma with all it’s specialist video processing to do the picture processing and not for something(s) cheaper in the food chain (not build specifically for that job) to do the conversion (and add noise) along the way.

I don’t think the Plex and the Kodi guys would spend so much time working hard to do passthrough for DTS-+ HD MA (and also the other HD formats) if lots and lots of people didn’t think it makes a big difference and the end result would be just the same as Plex converting to PCM.

Perhaps we should agree to disagree :slight_smile: …just don’t vote for this functionality if you think it is pointless :slight_smile:

11

So, here’s a horrifying discovery (now that I’ve put 40+ albums into nice MKA files with metadata and cover art): When using the desktop Plex Media Player, MKA files are transcoded to stereo MP3. #-o

Naked DTS files use Direct Play, and the PS4 client still gets multichannel AAC as before.

This sucks since PMP was the only one that worked close to correctly. It took me this long to notice because it’s rarely worth the effort to hook my computer to my stereo, but I would at least like to have the option.

Am I missing a setting somewhere? Is this a bug? Seems like PMP should be using Direct Play for all formats unless bandwidth just won’t allow it.

12

@Skurfer87 said:
So, here’s a horrifying discovery (now that I’ve put 40+ albums into nice MKA files with metadata and cover art): When using the desktop Plex Media Player, MKA files are transcoded to stereo MP3. #-o

I reported the issue. I am pretty confident this gets resolved.
If you could send me an example file with full embedded metatags it’s be even better. That way we could lobby to have PMS actually reading them.

13

Thanks, @OttoKerner. I’d be happy to send an example file.

  1. How should I get it to you?
  2. Do you care what kind of audio stream is inside? I’ve got about everything.
14
  1. a download link for Dropbox or Google Drive or any other ‘sendfile’ service would do the trick. per forum private message.
  2. It doesn’t matter what’s inside. The shorter the better, just to keep file sizes down.

It’d be practical to know what is actually in the metatags of the file. So the developer can verify he did it right :wink:

15

I finally cleaned up and documented the scripts I’ve been using.

Also, I couldn’t find mention of it in the release notes, but if I’m not mistaken, the tags are being read from MKA files now. Either that, or the world suddenly and collectively learned how to correctly capitalize track names.

16

@Skurfer87 said:
I finally cleaned up and documented the scripts I’ve been using.
GitHub - skurfer/Tractor: The Track Extractor

This might be useful indeed for many a music enthusiast.
Thanks for putting it together!

Also, I couldn’t find mention of it in the release notes, but if I’m not mistaken, the tags are being read from MKA files now.

Not to my knowledge. Title Case may be applied now automatically to file names.

17

Not to my knowledge. Title Case may be applied now automatically to file names.

Or maybe it’s reading the file names, but finally stripping off the leading digits. In any case, the matching process seems a lot more reliable. All I have to do is fill in the release date now (and in some cases, find better artwork).

18

Hi, if i play DTS music or 5.1 in plex media player on win 7 with passtrought in 96khz dts active, the music play to fast… ratio 1.3.
All DTS or 5.1 music have same problem.
Audio drivers reinstall - fail
PMP reinstall (local data deleted) - fail
Idea?

19

FWIW, it seems there are still some issues playing surround music - I downloaded some 5.1 tracks and while all my movies with 5.1/7.1 (E)-AC-3/TrueHD/DTS(HD MA) all transcode correctly to 5.1 AC-3 on my chromecast ultra which goes to my 5.1 setup, the FLAC 7.1 audio just gets transcoded to stereo, both when casting to the chromecast ultra from Plex android and from Plexamp.

    Codec FLAC
    Channels 6
    Bitrate 3034 kbps
    Album Gain -3.91
    Album Peak 1.000000
    Album Range 21.240821
    Audio Channel Layout 5.1(side)
    Bit Depth 24
    Gain -3.91
    Loudness -18.44
    Lra 19.63
    Peak 0.915891
    Sampling Rate 48000 Hz
    Display Title FLAC (5.1)
    Extended Display Title FLAC (5.1)