right a few things ive never heared of but here goes, some other people may be able to help more hopefully.
13. phase switch or dial knob. is to do with the timing of the sub , only ever seen it on the active sub things and it never makes much difference. id just leave it off unless you notice like a lag/mismatch between the sound from the spks and from the subs.
14 . infrasound filter switch. this gets rid of sound that is produced by equiptment but you cant hear it, you may want to switch it on and set it to.....
15 . IF sound adjustment. set to the lowest frequency the sub can produce ( mentioned below)
16+17 . I wouldnt bother with these adjustments unless you fancy messing around. it appears to basically be a way of stopping rattles, look at page 7 of the instructions and you will kind of get why I say not to bother.
18. lpf ( low filter ) switch. cuts off frequency HIGHER than a set value, ( very useful, turn on look at point 20 for settings)
19. gain (level adjust) . similar to vollume control but not, needs to match the output of your HU. very easy to match really, what you need to do is, first turn this knob on the amp right down, then If the HU has a 'sub output level adjustment' feature built in turn that to 0 ( or the middle value) then set the HU speakers ( if your using them) to the sound you would like ( so low,mid and high adjustments ) then start the engine! and turn up the headunit as loud as it will go without distorting or the loudest you want to listen to it (with a decent sounding CD in, it will need to be something with pretty constant bass, if you want some test tones let me know and ill send you some.), then turn this knob on the amp up until the subs start to 'clip' (or sound bad!) then back it off a small amount.
20. lpf adjust controls the cutoff point of the low pass filter. so if you set it to 30hz nothing above that will be produced ( so thats good for subs) the exact number to turn to will be determined greatly by the subs but also personal opinion. when you get the subs ( or if you allready have) look at the frequency range listed ( or find it on the net) it will look something like 20-22000 hz or whatever, turn the knob down as low as the smallest number listed here ( but i wouldnt go lower) . the lower you turn this knob, the less of the higher punch notes the sub will produce. so if you only want them to shake, not punch, turn it low!
sorry its so long but it kind of needs to be to cover everything. ( you might want to copy and paste to wordpad or something and print it! )
hope at least some of this makes sense, ask again if it doesnt!