Roku Device Features, Settings & Updates

Help configuring Roku device settings, using Roku OS features such as screen mirroring, adjusting display type and audio settings, using Guest Mode, and assistance with software updates.
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Heyitsrick
Level 12

2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

I just saw Roku's product page for the 2020 Ultra. Features and specs are published.

2020 Roku Ultra Product Page / Specs 

One thing of note: It explicitly says that Dolby Atmos is decoded in the 2020 Ultra. The 2019 Ultra simply says that Atmos is passed-through via HDMI. Interesting...

Dolby Atmos Decode Ultra.png

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45 Replies
andyross
Level 15

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

It's hard to know what they mean by decoded. I'd think decoding would mean breaking it up into a separate channel streams, which doesn't make real sense. It may just be a badly worded description. I guess we'll have to wait until people actually try to use it.

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Heyitsrick
Level 12

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through


@andyross wrote:

It's hard to know what they mean by decoded. I'd think decoding would mean breaking it up into a separate channel streams, which doesn't make real sense. It may just be a badly worded description. I guess we'll have to wait until people actually try to use it.


I can't speak for Atmos (I don't have an Atmos-AVR), but the Apple TV 4K decodes surround audio in the box and outputs it as multichannel PCM - unless you specifically set something different.  If I access a Dolby Digital Plus stream, my AVR will get it as PCM (multichannel) from the Apple TV 4K.

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StreamerUser
Level 16

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

Device-based Dolby audio decoding is a requirement for NetFlix Atmos (NF's requirement), so in order to support Dolby Atmos on NetFlix this was a necessity, especially given the Dolby Vision support (it would be silly for NF on the Roku to have DV support but not DA support, and is probably not allowed by NF anyway - they probably also require any device that wants NF DV support to also have DA support, which requires device based Dolby audio decoding).

You may also notice that recently released RokuOS 9.4.0 build 4155 available for current player models removes/changes the audio options (aside from the 4640 due to decoder and optical output):  you can no longer manually select the connected device/system audio codec support level (its only "Auto-detect" or "PCM-stereo" now) for "HDMI", and "Auto (...)" and "stereo" for audio mode.

This change was most likely made anticipating the decoding capabilities of the 4800 (Ultra 2020) - it most likely retains the older manually selected HDMI modes (at least in terms of Dolby audio), and those would actually indicate decoded/transcoded output levels - to avoid confusion with player models that cannot decode/transcode, the previously confusing/misunderstood "detected device capabilities" audio settings were removed (they were in fact, confusing since most assumed these were decoding/transcoding settings though they werent).

The 4800 will likely (hopefully?) have a (labeled?) setting for passthrough versus decoding/transcoding, output mode, but all that remains to be seen (they could assume/presume that "auto"=passthrough and manually configured everything else=internal decode/transcode).

The best speculative insight of how this is likely to be handled in the 4800 (before release obviously) is with a 4640 that has 9.4.0-4155 installed, so if somebody with a 4640 and 9.4.0 could check/test/comment, that would be good...

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Heyitsrick
Level 12

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

That's a great post - and it makes sense on the Netflix front.

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krazyankee321
Level 7

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

Since the spec on the 4800 only shows HDMI 2.0b, I assume that it will only pass Dolby Atmos in a compressed form (Dolby Digital +) to an AVR?

I believe that HDMI 2.1 is required in order to pass lossless Dolby Atmos to an AVR.  Has anyone tried this yet?  

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mcleanmb0
Level 8

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

I'm not an audiophile by any stretch, but does this mean that the 2020 Roku ultra will now decode/be compatible with Dolby Atmos via Netflix? I am sick and tired of switching over to my Apple TV plus device every time I want to watch something in Dolby Atmos on Netflix. Sounds like the new one is compatible?

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Lparsons21
Level 9

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

Yes the 2020 Roku Ultra will play Atmos from Netflix.

mcleanmb0
Level 8

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

Thank you very much! Just ordered on Amazon. Now I can do my once per year rotation of the living room Roku to bedroom Roku, with the 2020 becoming my new living room Roku! 

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StreamerUser
Level 16

Re: 2020 Roku Ultra - Dolby Atmos is DECODED in the Ultra, not passed-through

@krazyankee321 wrote:

Since the spec on the 4800 only shows HDMI 2.0b, I assume that it will only pass Dolby Atmos in a compressed form (Dolby Digital +) to an AVR?

I believe that HDMI 2.1 is required in order to pass lossless Dolby Atmos to an AVR.  Has anyone tried this yet?  


There's some confusion there - HDMI 2.1 is only required to pass lossless through its subset feature eARC (e.g. when connecting through/to a TV, then back to an AVR/soundbar/etc via eARC).

HDMI 1.3+ is required to support lossless (DTHD/Atmos) audio bitstreaming.

@mcleanmb0 wrote:

I'm not an audiophile by any stretch, but does this mean that the 2020 Roku ultra will now decode/be compatible with Dolby Atmos via Netflix? I am sick and tired of switching over to my Apple TV plus device every time I want to watch something in Dolby Atmos on Netflix. Sounds like the new one is compatible?


Yes, it supports NF Atmos - however, in the 4800's (Ultra 2020) default audio setting (Settings/Audio/HDMI="Auto detect"), it will transcode all audio to the highest detected connected-device Dolby level. (e.g DD+/Atmos or DTHD/Atmos or MAT 2.x/Atmos - you don't want this).

You'll want to immediately change it to passthrough mode (so that all audio remains in its original streamed format):  Settings/Audio/HDMI="Auto passthrough"