Man I got these 12in subs in a sealed 1.25cf box. They are kicker dual 4 ohm cvr subs, but the problem I have is that the subs make a whole lot of pressue in the car and make the whole car shake pretty good but the subs themselves dont have much sound coming from them at all. How do I make the subs sound loud like BOOM and stuff. Oh yeah I have an 325watts RMS to each sub.
Put them in a ported box instead of a sealed.
Are the subs in the trunk of a car? This could be the problem because alot of the bass may not be making it's way into the passenger compartment of the vehicle. If this is the case you might try cutting a hole in your rear deck so the bass can filter through into the passenger compartment and you can hear the loud BOOM more. Also you might consider sound deadening the space around where the subs are partically if they are in the trunk area. This will make the bass from the subs sound A WHOLE LOT BETTER because you won't be losing the BOOM sound to outdoor road noise coming into the passenger compartment. I hope this helps.