enclosure (sealed or bandpass)

I have a pair of performance teknique 12" subs in an bandpass box with an 800watt performance tek. amp.it sounds aight but i think it can soung better.I was wondering would it sound better in a seal box.

Did you have a box built, or did you put them in a premade box.  Sometimes if you put them in a premade box you won't get the best performance out of your setup, especially dealing with a bandpass box.

99% of the commercially sold bandpass boxes will not acoustically match any subs out there. Unless they are matched very closely to the T/S parameters of your subs, you'll either get sadly inaccurate performance (even with the best subs) or you'll have a "one-note monster."
     If you can find a sealed box that has a matched internal volume, you'll see noticeably more accurate performance, but you might also notice less thump. What type of music do you listen to?

CTW
MECP Sales

you are pretty much always better off to custom build any box to the specs of the subs you have...prefab boxes are a poor idea, because nothing is optimized...

typically, with a sealed box, you will get better sound quality and increased power handling...the music often seems a bit tighter and livelier...if you are after SQ then this is probably the way you want to go...you may lose some volume (depending on the boxes you have now) but you should gain some clarity and cleanliness...