The definitive DTS-HD sound work-around for the Sonos Arc
Hello all, I thought I would share my work-around for this much derided problem: lack of support for DTS sound on Sonos’ so-called home cinema set-up. So called, because, it does not support the sound encoding used on *most* Blu-ray Discs. I say most with good reason, out of the 100 discs I have of the most popular and mainstream films, 80% are DTS-HD.
For the Play Bar I had a decent work around which produced DD5.1 or DD Stereo (see here: https://en.community.sonos.com/home-theater-228993/dts-dolby-5-1-on-playbar-2015-edition-6731191).
For the Arc it was really annoying to have to even look for a work around, however, I think I have a solid one. Bit it does require you to be much more technical and basically, be capable of ‘ripping’ or copying your Blu-ray Discs. Before I went this route, I looked for every transcoder, box, set-up going but there is nothing. I even though about returning the Arc or buying a second one to use for DTS alone, which was a bit mad.
As it happened I just bought the Zappiti 4k system (which is amazing!!) and was in the process of transferring my BDs to it when the Arc arrived and presented this problem. This is what I did.
Set up
I made 1:1 copies of the disc using AnyDisc and MakeMKV. If you don’t want 1:1 copies for your media system/set up, you can skip this. You will need a vast amount of space...
I was able to play all Dolby encoded discs from the Hard Disk and experience TrueHD, Atmos etc. The Arc is absolutely magnificent, with a Sub and two rear Play 1s. However, even by itself, it is very impressive. Really towers above the PlayBar; kudos to Sonos. Highly recommended Atmos film: First Man--skip to the take off scene. Will blow you away!!
Transcoding to Dolby Digital Plus
To play DTS-HD, DTS5.1 or DTS I used Handbrake to create MKVs of the main movie (ie the single title on the disk--Handbrake will usually find it for you). Why Handbrake? It was the only software which definitely converted DTS-HD to Dolby Digital Plus. All other open source applications did not; only to DD5.1 using AC3, with a bitrate limit of 640kbps.
Re-coding to DD+ uses the E-AC3 codec and it works on the Arc with a bitrate of up to 960kbps. I don’t know why 960kbps as DD+ (which the Arc supports) is up to 1.5mbps but I only got silence once I exceeded 960kbps. I tested this many times with many discs.
E-AC3/DD++ is better than AC3/AAC and DD5.1 as these are limited to a bitrate of 640kbps. 960kbps isn't great when we are downmixing from HD sound, but better than 640kbps. Using Handbrake with the mixdown set to 5.1 channels (using E-AC3), the mkv produced was recognised by the Arc to be 5.1 channel Dolby Digital Plus.
As a result, I could experience much better sound than PCM/stereo.
Please note that I had set my Zappiti (ie media player) to pass through bitstream so the sound send to the Arc via my TV was the sound played by the MKV file.
Dolby Digital Plus is quite a rare find on disc, however, it is really good, rich sound. I don't think you can easily tell that its more comparable with “standard” 5.1 sound compared to HD sound.
Ripping/making MKVs
Making MKVs from Blu-ray Discs are really straight-forward but is no substitute for an “on the fly” solution or Sonos support by way of a firmware update. However, for those who want to move away from physical discs this works very well.
Regards!