What level should I be adjusting my LPF and Gain control?

Hello,

So this is my first Amp in many years, So I am still unsure as to the best way to have the levels set on my Amp?
I have the ISF (infrasonic filter) switch set to cut out everything below 15Hz.
Now as for the LPf (Low-Pass Filter), What should I have this set to.
I mostly Listen to Hard hitting Rap and Hard Classic Rock. So Can someone suggest a level that I should be setting it too?
And as for the Input Sensitivity Control, Any Advice for that?

Please help
Thanks

I didn't find the right solution from the Internet



References:
www.caraudioforumz.com/car-audio

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