What is soundbar?

In plain language

ARC or eARC: sources connect to the television, and the TV sends audio back down one HDMI cable to the soundbar. The soundbar is not in the video path at all. Passthrough: sources connect to the soundbar, which extracts the audio and passes video on to the TV.

Why it matters in your setup

Passthrough puts the soundbar in the video path, and its HDMI ports may not support what your sources and television can do. A soundbar with 4K60 inputs will cap a 4K120 console, and its EDID handling decides what the source is told.

eARC keeps the video path clean but shifts the problem: the TV must support eARC on the right port, both ends must have it enabled, and the cable must carry 192kHz audio for Atmos.

What the DR HDMI 8K does with it

If your soundbar is in the video path, a DR HDMI 8K in front of it lets you control what the source is told rather than accepting the soundbar's advertised ceiling — and its audio flags show you exactly which formats the soundbar is claiming.