Originally Posted by Ellebob
I agree that compressions depends on the source and NONE of the major services like Netflix, Hulu, Amazon, Vudu use PCM or any lossless format, they mostly use DD or DD+ for Atmos. Now when dealing with compressed formats how they get transcoded can make a difference because they try to fill in the missing bits that were thrown out during the compression process. Some devices have better algorithms for this than others. Back in the DVD days when all there was compressed formats it was usually preferred to have the receiver (there weren't sound bars) decode the compressed stream instead of the DVD player because their algorithms were usually better with a few high end players as an exception. The same could be true of the SJ9, it might transcode the DD stream better than the Apple TV. It would be a try and see which one does better. If you have sources that have multi channel PCM (RARE) then I would absolutely use PCM, otherwise use whichever one sounds better. The SJ9 might do a better job decoding DD then the Apple TV. In fairness it is probably splitting hairs.
I was just pointing out that because this is an Atmos sound bar you might change this setting in the future and it might not be the best setting now. We don't know how Apple or if Apple is going to implement it and what the menu choice will be. They said they were going to implement Atmos but that was about 8 months ago.
I get it, and I think we’re both on the same page, but to the original poster’s concern, there’s absolutely nothing wrong with his/her signal chain. Which device should be handling possible decoding/transcoding is a separate concern, and the fact is that the ATV does not offer 100% bitstream passthrough (which it should, I agree), so it’s a moot discussion here.
Now in terms of the future, I would assume the “Best Available” setting would likely remain the same and have some sort of “allow atmos” setting available that would passthrough atmos/DD+ bitstream on those sources only, but that’s purely speculative. Or perhaps they will offer native passthrough for everything, which would be great.
Pre-encoded multichannel PCM may be rare, but case-uses for uncompressed and/or multichannel PCM aren’t rare. Airplay sends lossless audio (2 ch stereo) to the ATV. You wouldn’t want to then compress this into DD/DTS by forcing those output options. Also, many games on *other platforms* use multichannel pcm, though to your point, I’m not aware of any on tvOS.