Ok guys,first of all hello to everyone,im new here and sorry in advance for my english since it is not my main language,and for my ignorance about Sub's,Boxes ,and similar I am getting myself a 15" MB Quart Reference series RWE 352 subwoofer : (Source:Google ) It's 700w rms,1400 max,15",and im getting it very cheap from a friend,its almost brand new ^^ Problem is,i asked couple of guys,and saw on net that its recomended for this Sub to go in Sealed box 50 liters~....I already have a 300w RMS 10" Radical Audio subwoofer in a 26l sealed box,and ...weeell im not satisfied,i mean,its clean,fast precise bass,but just aint louuuuuud :/ So im kinda concerned how will it be with sealed box with this 15" sub ,considering its 5" bigger ,and more then 2x more powerfull,i want it to have a decent boom,hit good,and have decent quality if possible I was wondering,how would this subwoofer sound in a normal bass reflex box? and how big it should be since 50l~ is recommended for sealed box? It will be powered by 600w rms Impulse sd-500 amp which is i think just fine for this subwoofer. If anyone can help me,to tell me how will it behave in BR box,and give me dimmensions for box i should make ,since i cant calculate that alone lol,too bad at math,id be sooo grateful By the way,car is a 3 door hatchback,2005 alfa romeo 147,so trunk is connected to cabin if means something Here are thiele small parameters of this SUb. i menaged to found if its of any help: RE - 3.2 QMS - 5.52 QES - 0.481 QTS - 0.443 FS - 24 VAS - 210 Thanks in advance people,and sorry again for my ignorance and bad grammar,also if i missed a section to post this thread ,please can someone move it?