Spud88

01-21-2013, 11:07 AM

Hi guys,

Im new to the forum and was wondering if anyone can help me. I have got an alpine swr 1242d type r 12" woofer and i want to build a slot ported box for it. I have read loads of posts about making boxes and working out port length and area. From what i have read its optimal to have a box between 2-2.5 cubes tuned between 30-35hz. I have used various enclosure and port calculators and have come up with some numbers that id like you all to verify for me. The outside dimension's are h15" w26" d16" with mdf .708" thick. I have worked this out to give me a gross volume of 2.818ft^3. Now i have worked out the port to be 13.6" tall 2.5" wide with a length of 28.5"(not sure if length is right for 32hz tuning?). I have worked out that the volume of the box minus the port will be 2.257ft^3. So i worked out the volume of the port wall to be .218ft^3 so a final net volume of 2.039ft^3 with hopefully a tuning of 32hz. Can someone please tell me if these figures are right or if i have just wasted half a day trying to figure this out?

Many thanks

Luke

Im new to the forum and was wondering if anyone can help me. I have got an alpine swr 1242d type r 12" woofer and i want to build a slot ported box for it. I have read loads of posts about making boxes and working out port length and area. From what i have read its optimal to have a box between 2-2.5 cubes tuned between 30-35hz. I have used various enclosure and port calculators and have come up with some numbers that id like you all to verify for me. The outside dimension's are h15" w26" d16" with mdf .708" thick. I have worked this out to give me a gross volume of 2.818ft^3. Now i have worked out the port to be 13.6" tall 2.5" wide with a length of 28.5"(not sure if length is right for 32hz tuning?). I have worked out that the volume of the box minus the port will be 2.257ft^3. So i worked out the volume of the port wall to be .218ft^3 so a final net volume of 2.039ft^3 with hopefully a tuning of 32hz. Can someone please tell me if these figures are right or if i have just wasted half a day trying to figure this out?

Many thanks

Luke