video connect

Auxinput,
In regards to the ROKU if installed, I would no longer be using the streaming function of the LG OLED?  So connection for video pass through would go as follows: modem to Roku via ethernet
Roku to Lyngdorf via HDMI in
Lyngdorf to LG OLED via HDMI out.

What about Audio? would both signals, audio and video, be delivered to the Lyngdorf via  HDMI from the ROKU to to the Lyngdorf HDMI in?
What about the EARC HDMI of the Lyngdorf?

Correct, you would no longer be using the streaming function of the LG OLED.  The LG TV would now become only a video output display device.

Yes, both audio and video signal would be part of the HDMI cable connection from the Roku into the Lyngdorf.  The Lyngdorf would pass along the HDMI signal to the TV so that you get video.

You are correct in all your assumptions.

Using ARC is sort of a backward way to get a digital audio signal "generated" by the TV (using either a channel tuning or a streaming app in the TV).  It is not as good because you are limited to old school Dolby Digital / DTS and it uses a single wire in the HDMI cable to "talk back" to the Lyngdorf.  You will have to manualy switch the Lyngdorf into "ARC" mode when you want to do this.  However, it's always better to use a real A/V source to supply audio/video into the Lyngdorf, such as a Roku or a bluray player.

ARC was developed really for those types of people who just want to throw a TV up on the wall and expect it to do "everything", but then later wanted to add an audio system into the mix as easy as possible.  They don't want to mess with different sources (i.e. Roku, bluray, satellite receiver, etc.).  ARC is not the "audiophile" way to go.  It is really a "convenience" feature.

Thank you.

I need to make a correction on the Roku Ultra DC plug size.  It is actually 4.75mm x 1.7mm.

Ok thank you for the good explanation