Asus Audio Card Xonar D2 User Manual page 26

5.2.2 Connecting 5.1 channel Headphones
No Item
1 Front Out
2 Side Surround Out
3 Center/Subwoofer Out
20
Description
Connect the front-channel 3.5mm plug of your 5.1
headphones into this jack.
Connect the surround-channel 3.5mm plug of your 5.1
headphone into this jack.
Connect the Center/Bass-channel 3.5mm plug of your 5.1
headphone into this jack.
ASUS Xonar D2
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