WARNING: Beam does not support Dolby Digital Plus, That is a BIG deal

Word of warning for anyone looking at the Beam to start a 5.1 surround sound system, it will NOT work ideally for any streaming box except the Apple TV. I would suggest really doing your research and/or staying away from the Beam if you want a home theater solution.

The Beam does not support Dolby Digital Plus (DD+) and only supports PCM (poor quality) or Dolby Digital. Why does that matter? DD+ is the current standard. Dolby (the only thing Sonos support) sounds good but is hardly used anymore by anything halfway modern. PCM is the audio equivilent to standard definition TV.

DD+ is the de facto standard for streaming boxes and services. Hulu, Netflix, HBO and I want to say Plex support this standard and only this standard. Those services do not use Dolby Digital. To get Dolby Digital, that means the stream must be downconverted (transcoded) on the fly by either your streaming device or your TV before reaching the Beam. If you do not convert, you are forced to use the poor quality PCM.

Now here's the rub. Few TVs downconvert. If you have one that does? Great! You should have few problems. Thing is though today, few streaming boxes do as well. In fact, the only one that does that I can tell is the Apple TV 4K. The nVidia Shield does not, nor does any modern Roku device. The 2016 Ruku Ultra does, but the 2017 and 2018 models do NOT. Looking at Roku forums, a software update from Roku may have removed that option thus meaning no Roku converts DD+ to D.

I can not believe Sonos is selling a device, geared for home theater, that does not support what is a very common standard. Every single streaming device support DD+ along with all the major players including Netflix and Hulu. It is THE standard, yet Sonos does not support it.

Keep this in mind as you're researching. I find it very disappointing, and will be returning my Sonos products.

I think it’s the latter. I don’t think TVs do any transcoding at all, but pass the “request” received by HDMI-CEC from the Beam back to the source device, and it is up to the source to send the appropriate signal, even if it doesn't show up as a normal audio option in that device’s settings.

However, this is speculation on my part. There’s an internal logic that appeals to me, but I haven’t researched it. One of these days, I’ll look up the HDMI-CEC spec and see what it says about passing that data request back to a source. Or, if there’s a video engineer willing to confirm or debunk my theory, it would be nice to have an authoritative source.  

Not so puzzling to me. Simple cost. Why add $10 of electronics that 99% of users won’t ever use? Better to meet a price point to sell the TV.

But my general expectation/concern is that this feature will soon disappear from Blu-ray players, gaming consoles, Apple TV’s etc. because it is mainly serving to support an ancient file format that almost all manufactures of amps and soundbars have abandoned years ago.
 

Once that happens and every streaming service and Blu-ray will have moved on from DD 5.1 to DD+, DTS, Atmos or what else is coming, Sonos will be nothing but stereo. 

DD 5.1 is also the ATSC standard multi-channel format in the US, Mexico, Canada, and other countries.  Any station broadcast in HD with multi-channel audio is required to use it.  As such, It ain't going nowhere.

But all is well. If one is fine with watching non-HD DVDs and prefer flow tv rather than the crazy haze of streaming, Sonos will be the perfect partner - just as in the good old days

90% of my watching is streaming, and I’ve not found a single streaming service that does not offer DD 5.1.  I’m also someone who won’t buy a soundbar for my main system, and thus I have a modern wired surround setup with capability for all current formats.  Just so happens my room is such that anything more than 5.1 would be overkill.  In short, I’m not worried about DD 5.1 leaving any content I view and that has nothing to do with defending Sonos’ soundbars (which I have criticized from the start).

ARC and Optical cannot physically support DD+ and can only support 2 channels of PCM. As an ARC and Optical only product, it's not even an option for them to support it.

Also,another tip. PCM is uncompressed audio. It is the farthest you can get from poor quality. . It is 1,411 Kbps PER CHANNEL at CD quality, which is lower than Disc based LPCM streams. Dolby Digital is compressed and lossy at 640 Kbps FOR ALL 6 CHANNELS COMBINED. Just a tiny difference...lol

5.1 channels of uncompressed audio would be 8.466 Kpbs aka 8.5 Mbps. More channels, do the math. Thus the advent of Tru-HD and DTS Master Audio...aka Lossless codecs. The quality of uncompressed audio without the huge bitrates.

The issue is that ARC and Optical do not have the capability to handle the large bitrates. The bandwidth limitations of ARC and optical allow for only 2 channels of PCM and the DDP, Dolby True HD, DTS-MA data rates also exceeds the bandwidth limitations as well. ARC and Optical output is the exact same digital stream (SPDIF) simply going out whichever of the two outputs you tell it to.

The fact is here, 99% of Sonos customers could not tell the difference between Dolby Digital and Dolby Digital Plus. Especially through a Beam alone. The drivers are too small and the electronics too low end to make it possible. You'd need to be at a significantly higher price tag and quality level of hardware before it would be tangible to the average Sonos consumer.

Matter of fact, you can go full 5.1 Sonos and still it would go unnoticed. An simple enthusiast would notice DTS vs Dolby Digital LONG before they would notice DDP vs DD. DTS is a significantly better performing decoder than Dolby, and has been for many years. However, Dolby has done a fantastic job of marketing the brand, especially Atmos. With Blu ray's going the way of the cassette (you see Samsung announced they are no longer making Bluray players..at all anymore.), and DTS being the dominant player in that space...they have reason for concern looking forward.

Nonetheless That's a big part of the reason why you don't have DDP. You wont hear it. The other part of that is that in order to offer DDP, they would have to pay a higher royalty to Dolby per unit sold.

If you wont hear it, why the hell would they pay it? It's giving away money and they are a public company now.

It's just business folks.