LG USC9S Owner's Manual page 14

Speaker sound based on input channels
Sound Effects
Output
Input
Rear speakers not connected Rear speakers connected
AI SOUND PRO
Sound customised with artificial intelligence
2.0 channels
5.1 channels
7.1 channels or more
7.1.4 channels
STANDARD
You can enjoy optimised sound.
2.0 channels
5.1 channels
7.1 channels or more
7.1.4 channels
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