Also keep in mind that many Roku channels use Dolby Digital Plus for 5.1 surround sound, and that is not supported over optical connections. Thus, if you watch content from those channels, you'll only get stereo audio from the Roku (although your soundbar may be able to provide simulated surround).
The 2016 Ultra (Model 4640) had the optical out...but it was removed in the 2017 Ultra (Model 4660). If optical is a must for you (and it sounds like it is)...I'd return your Model 4660 and try to find a 4640 (although be aware of the momentary screeches that some of us are getting with the optical-out on the 4640). In addition to having the optical out, the 4640 is able to take a 5.1 Dolby Digital + input and transcode it into standard 5.1 Dolby Digital for passage over the optical output. This alleviates the issue that kpfleming spoke of.
This is a horrendous decision to remove the optical out. It was one of the few to do this, and properly (the nVidia shield has almost everything but the optical out and this was one of the major reasons to get the Ultra, especially if you wanted to have your Roku connected directly to your TV and use TV (plus soundbar if you wish) speakers without having to also have a receiver and turn on the receiver!!! Pitifully bad decision.
I've seen some HDMI to optical cables. I can't say how well they work but you can check at the usual places and se the reviews.
"kpfleming" wrote: Also keep in mind that many Roku channels use Dolby Digital Plus for 5.1 surround sound, and that is not supported over optical connections. Thus, if you watch content from those channels, you'll only get stereo audio from the Roku (although your soundbar may be able to provide simulated surround).
Isn't that what all soundbars do since they are only 2.1 systems?
"Miami Son" wrote: Isn't that what all soundbars do since they are only 2.1 systems?
You can get 5.1, 7.1 and 9.1 soundbar systems.
Most people have 2.1 soundbar systems. Anyone using a 5.1+ soundbar system isn't really interested in the highest quality audio for their home theater system.
That might be your opinion, but I know several people that do care about their audio quality, but prefer the simpler setup of a soundbar. In fact, I believe that I am in the minority of people that have a full 5.1 audio setup in the bedroom. And I believe you can find quite a number of soundbars that perform quite well.
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