more bass

ok so i finally bought everything for my system thanks to everyone for the dos and donts and recommending what would be best.  i ended up with a mtx tc4001 mono amp and two jl 12w1v2.4 subs in a sealed box and a factory headunit and a pac trunk loc as a loc. it thumps pretty good now but the loc has two adjustments on it and i was wondering what they were for?  i also wanna know is there a certain way i should have my gains set since its connected to a factroy hu? i am trying to get evey last bit of bump out of this system and every little suggestion helps

                                                                                                                                              thanks.

'every last bit of bump' -go ported! You could try downfiring the box you have now. As for the gains, you want the one(s) on the LOC as low as possible. Use the one on the amp. What kind of car?

Get the manufacture recommended ported enclosure volume for the subs and use this: https://www.the12volt.com/caraudio/boxcalcs.asp#por to get it tuned right. I would tune it to about 50-60Hz for 'streetbass'.

Built it right (sturdy) and have fun!

The adjustments knobs on the LOC are for setting voltage gain to the head unit's voltage output.  It's not really science but just trial and error.  Start with the knobs turned all the way up and adjust slightly downward as you listen.  It's a matter of making a little bit of adjustment, then adjusting the amp gain, then listening...then a little adjustment, a little adjustment of amp gain, then listening...

You get the picture.

It is entirely possible to set amp gain with the LOC gains in any position.  The benefit that you get by having those gains is that you can set the LOC to closely match the voltage output of the factory deck.  OEM decks come in a wide variety of flavors.  Some are very well made and others are complete crap.  What is common, however, is that they all will output at a higher voltage than the aftermarket decks will.  That doesn't mean, though, that they will sound better...often they sound worse...but voltage is higher.  The only way you can benefit from that higher voltage is to be able to adjust the device so that it matches your particular deck's output.  Listening is the key...and give it plenty of time and several adjustment trials.  The sound may be a bit tinny or shrieky - that shows you that you should adjust the LOC gains down a little bit.  Always start at the max and move downward, and remember that every adjustment of LOC gains means that there must be a followup adjustment to amp gains, because the voltage input has been changed.

As soon as you get to the point where everything sounds good, stop making adjustments.  At this time you should mark the gain knobs for reference and never touch them again.  If someone tampers with your gear, turn the knobs back to the marks and you'll know it's where they should be.