Don, do you have a particular device to give us context? I image it's going to be something like one of these:

https://www.hearingsol.com/articles/hearing-devices-to-watch-tv-with-hearing-loss/

Other than using the Sound Effect setting to toggle through the LG sound bar's sound profiles, I didn't see any dedicated vocal clarity setting, and there's nothing in the TV's accessibility options to enhance audio clarity.

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