You'll have to be a little bit more specific with your question(s).
The post you quoted contained several different questions.
First of all, there is NO difference in audio quality between ARC or S/PDIF (optical or coax).
Therefore, since you are connecting everything to the TV/OCM, it will not make a difference (quality wise) whether you use an Optical cable or an HDMI/ARC cable. If ARC is working fine for you, than stick with that.
Furthermore, I'm I correct that your Soundbar only supports 2.1 channels? If so, then you will not be able to output "true" DD or DTS surround sound - never mind DD+ or any of the HD Audio formats. You'd have to purchase an AVR (and extra speakers) for that.
Just a note about ARC and S/PDIF (optical or coax) for others reading this...
It is NOT possible to get any of the HD Audio formats over an ARC or Optical connection. The issue is with the "bandwidth" required to transmit those "lossless" HD Audio formats.
S/PDIF (Sony/Philips Digital Interface Format) and ARC (Audio Return Channel) - which uses two pins from the HDMI connector, a previously unused pin and the hot plug detect pin, to transmit the audio "upstream" from the TV back to the AVR or Soundbar - simply do not have enough available bandwidth to transmit those extra audio channels or HBR (High Bit Rate) audio codecs.
(Note: The term codec
refers to the algorithm used to encode the audio. "Codec" is short for coder-decoder.)
There are a few select TVs out there (some Vizios for instance) who are
able to transmit DD+
(Dolby Digital Plus) over ARC. DD+ can
carry up to 7.1 channels, as well as a highly compressed
form of Dolby Atmos object based audio, from the TV apps. However
, it is a "lossy
", low bit rate, audio format - it is NOT lossless
One reason most TVs (e.g. Samsung TVs) can't output DD+ is because they were built with "chips" that allow for just one audio output, and that audio is sent to both S/PDIF and
ARC at the same time. Therefore, DD+ content is downgraded to 5.1 DD before being sent out through ARC.
Again, it is NOT possible to send lossless, high bit rate, HD Audio formats through ARC or S/PDIF (optical or coax). It is simply a limitation of the technology.
Let me also point out that NO "on-board" TV streaming app support these lossless
audio formats anyways.
Wishing you a wonderful year filled with lots of great TV viewing!