There is a removable cover plate on the opposite side from your speaker connections on the amp. Under the cover, you will find controls for Ch 1/2, Ch 3/4 and the sub. Ch 1/2 & 3/4 should have the "filter"switch set for off depending on the type of speakers you have connected.
The LP filter (low pass) is straight forward for the frequency cut off of what will be for the speaker. The setting you want will depend on your taste and what your speaker will do. Look up what sub you have and see what its freq range is. Set the LP filter for that value aor lower depending on what you like. If the speakers in the front and sound bar are full range, then don't change anything else.
Just because you have one doesn't mean you have to act like one :-)
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