dbjunior

you should have no problem with 4 mj's then about a 25cu box tuned to 28hz would do nice

a box wouldnt be hard to design a box and 4 18's would be sick on a 2500d. do you have a 2500d already if so that helps money a lot? put the cap on and see how far from the bed floor to bottom of the window is and go from there if you want help let me know.

never mind the mj's are only single 4ohm you would need to get an ampthat puts 12-1400w at 2ohm like a kicker zx1500.1 of ebay for $400

with space like that your better off spending money on some large low power subs, like 4 mj18m's and a single saz 3000d or 2 and a saz1500 depending on budget or you could even try out the new sae-1200d. a sae-1200d and 2 mj18's is only $660 a large low tuned box and you would have a serious daily ground pounder.

large and tuned low like 2.5-3cu per sub after displacement tuned to 18-20hz. as far as port size, determine how large a box you can build and the calculate a port from there low tuning requires long ports aeros are nice, but it could be easier to make a slot port to get surface area and length. its tough to make long aeros without deep boxes. set your ss filter to 18hz and lowpass to 60hz should make a nice home theatre sub setup.

no do not get a cap spend the money on some good wire replace it with 1/0 and do the big 3 in 1/0 if that doesnt do enough get a yellow top for the back or some other agm battery if possible upgrade your alternator as well caps will do nothing when running way over what your car is capable of creating. if it was a 300w amp and you had slight dimming on some bass notes a cap would help

how much room do you have a ported fi q18 will sound worlds better and should get loud depending on box

just wondering why only 12's if you now have so much room why not do 18's.

9 Cubes after displacements. 33hz. for two18's and you call this a lowend box lol im doing a lil over 9c after displacement tuned to 28hz and its not as good on the lows as id like try larger and tuned to low 20's that would be a lowend monster even on low power. all the movement on put on at the low notes is just waste even mine would like a little lower tuning for the 20hz. its not a bad daily box but no lowend monster.

how about a 12in havoc ported in 1.8cu tuned to 32hz

i have my box tuned to 28hz and i have nice lows i have had the q in a 35hz and i didnt like it at all much better on music and better lowend with the lower tuning. if you can just save money on subs and have a new box built bigger and tuned lower like 10cu tuned to 28-30hz

p3000 are not that great but will be ok if you have the electrical saz 3000d is a much better amp and are cheap for the quality. you will need a killer electrical to power that much amp be prepared to spend a lot on that. daily setup will cost even more for electrical if just for competing a ton of batts should be enough but for daily you will need atleast 1 300amp alt and a bunch of batterys.

come on decent the cone and dustcap are illuminated blue they put more into making it look flashy than functional. looks like audiobahn type crap.

try an audioque sdc2.5 12 a 2cu @35 with 600rms will get you loud and still sound good and they cost 140.

update please

updates

wait what its only 12.3v at idle is there something wrong with the alt or is the vehicle off and its only playing off batts. it that the voltage at the bat ot amps

the massive p1500 is only a 1500wrms amp it should have no problem on the electrical minor dimming thats about it. idk how much you arepaying for 1500wrms but have you looked into the ma audio hk2000d will do same power but you can pick it up for like $250 with loud being what you are looking for and 1500wrms being the power try looking into the dp 18 or 21 the 18 is less than the btl loaded. your looking at 750 for sub and amp knuconceptz has 1/0 wiring kits for $60 2 sheets of mdf is 40-50 a nice pioneer headunit at walmart 150 a set of cdt cl-s60 100 and a pioneer gm 5300t to power them 115 just over 1200 and that includes the headunit and frontstage wires and wood for box. just need to save some money for some secondskin

looks incredible. how do you like the sound?

there is no way you have enough space to run them subs properly your looking at a 20 cu box 14 after displacement.

dont go to caraudioforum.com sucks a lot of spam ton of noobs and the few who do know stuff dont tend to help much anymore

are all the batterys the same type. possible diffrent type battery under hood could be causing problem.

as long as you keep voltage above 10.5v i believe they stay on so a strong alt and big battery bank should be fine for one. my buddy has one he uses for comps runs it off a hc2400 and a yellow top. powers 2 10bl's in a blazer and can do 149's consistantly. i know about ten other guys using them some using 16v systems some 12v none 18v

so far all you have is medium power level amps how about higher power levels like 4-6kw something good for comps but can handle daily abuse provided you have the electrical. possible ma audio hk4000d over rated but can be had on ebay cheap for the power proven in comps idk about daily

q's like larger boxes 20 cu might not be enough for 4 18's and with 5000w i think you would be better off getting the bl. it will like the 20 cu better and handle the power better. plus if you want loud it will do that better to.