there are trade offs for volume and the biggest is soung quality, there is likely a ported box that will work for your subs but 2 15's can pound and the idea here is a sealed box will work good, a ported box will work if tuned right but when you get into boxes that are disigned to give you an extra 1 to 3 decibles you must be exact and the cars volume could turn the last 3 dbs. into a poor sounding bass sound.
my advice is use the sealed or ported box, use sound dampening material and techniques and impress your people with good spl's of bass that is clean, responsive and powerful.
trust me the cobalt line is great but if i hear a car going down the road with bass playing i know if it is good bass or not, and your friends will know too maximise sound quality, if u went to a concert would you be happy with just bass?
my advice is use the sealed or ported box, use sound dampening material and techniques and impress your people with good spl's of bass that is clean, responsive and powerful.
trust me the cobalt line is great but if i hear a car going down the road with bass playing i know if it is good bass or not, and your friends will know too maximise sound quality, if u went to a concert would you be happy with just bass?