Car Stereos: bass sounds backwards, amp settings, boom boom

Question
QUESTION: wasap i recently installed a new duel touch screen tv in my car with a thousand watt amp and two twelves i got every thing hooked up thumping but i can't get it to sound right it go boom boom like ur punching the sub not quading like u hear other systems almost as if something is backwards or ur playing music through them as well but im not sure what can i do to fix this issue ?

ANSWER: Hi Robert,

Check the polarity on the subwoofers.  If they're hooked up backwards from eachother (one is backwards, one is correct), then they'll effectively cancel eachother out and sound very dull.

Also, make sure they're not sharing airspace (they should be separate).

Finally, make sure the box they're in is the right size for the subwoofers.  Most 12" subs need at least 1.2 cubic feet of airspace per sub.

Find some music that simply thumps with no resonance.  Make sure the subwoofers are both moving OUT on the thump.  If they're moving in, the polarity is switched.

Justin

---------- FOLLOW-UP ----------

QUESTION: Justin thank U i will defiantly try that my friend messed with the amp settings and got it to sound better but now when i ring the volume past for example 26 it sounds shitty and i switched it so the subs face the trunk not the seat as i was told that makes a difference so my friend told me though it's the amp that is junk and with a better amp the louder i go it won't get crappy is this true ?

Answer
First, your friend is right.  You want the subs to be pounding in to air space, not the back of a seat.

As for the quality of the amp, it's possible, but you're going to want to make sure everything is hooked up 100% correctly first, or changing amplifiers isn't going to make a difference.

Justin