the box I got designed is each chamber is tuned to 32hz but those FIs are only 35. Would I need to tune the chambers to 35hz instead. I dont know how i would do this bc every sub ive owned has been 30hz or lower and i had my kicker 15s tuned to 32hz and they slammed. and do you have an opinion on rockfor fosgate p2d4

Just because the Fs of any sub is higher than the frequency you want to tune to doesn't hurt a thing. My Q's have an Fs of 34hz and are tuned to 32hz as well. The Fs is simply the resonant frequency of the sub in FREE AIR. Once it's put in an enclosure that number changes anyway. Just because that X has an Fs of 35hz doesn't mean you can't tune it to 30hz or even lower if you so choose. 32hz tuning will be great with them.

I've seen people have problems with the Rockford dustcaps (the face of the cone as most people see it) cracking. Aside from that the Rockford is simply not built as well as the Fi's. Another thing about the Fi's is that if anything EVER happened to them they're readily rebuildable. Not something that you can get from the majority of other companies. Most, if they're out of warranty, tell you that you're screwed and if it's still under warranty just replace it with a new one. With Fi the subs are built to order in Las Vegas with all USA parts, are completely rebuildable and covered with the best customer service you'll find in the industry. IMO its hard to even compare the two.

Look at these subs. Guys are putting up 149's on the TL at the dash with 1600-1700 watts on a pair. Pretty impressive at $109.99 w free shipping.

WoofersEtc.com - E-12D2 - Sundown Audio 12" Dual 2-Ohm E Series Subwoofer E12D2

some questions
 

i got 4 dd 12s and need ideas on a box. should i have subs up and port firing tword the back or subs up port firing tword the front or side or just have subs and port firing tword the back. and i need ideas on amps i wanna stick with a monoblock

Well, this should suffice.

AUDIOPIPE AUDIO 3000W MONO CLASS-D Car Power Amplifier (784644413654) | eBay

As far as a box, look at this video and you should get an idea.

http://www.youtube.com/watch?feature...&v=zz8j2qNTxS8

audio pipe is cheaply made and with there 3000w amp you might get 1500 of it. i used to run an old audio pipe setup

i already got 4 dd 12s. i got them for 100 ea.

i personally prefer kickers rockford fosgate are more so made for power, while kicker is for sound quality. and since your putting 4 in, your tyrucks gona hit hard no matter what. so id suggest buying a sub that you like the sound quality of, such as kicker, alpine, maybe polk. but if you are still wanting to buy the lower budget subs, go with mtx. however, on amazon's website there is an 800 watt rms pioneer that sounds pretty decent for a good price. goodluck!

for a 100 a piece? What series? the 1512 or 2512? Hell of a deal man, those things will get stupid loud......

on a beefed up electrical, the 3000 will get 2700 at 1 ohm at around 14.5 volts.....

http://www.youtube.com/watch?v=UR8uYOHKTsk