ayyo its simple ban..
just buy a cheap 2.1... (around1500)
buy a at least a 6" double magnet woofer.. (normally around 1000)
make a box for that.. (another 1000)
buy a matching amp for your speaker.. (max 2000)
:P
what i was did to my second pc's speakers is...
just removed the small 4" sub and...