View Full Version : Help with Single Alpine 12" Type Box

07-12-2008, 02:17 AM
Hi this is my first time posting on this forum so bear with me....
Ok i have a single 12" type R and a 500watt RMS amp and plan to make a ported box for it around 2.5-3 CuFt and i was wondering if I wanted to get the most SQ and SPL possible a freq of 33hz should be fairly ideal right? and also i want the box to be as least deep as possible. So for say a 3Cube box wat would the port dimensions have to be for it to be ~33hz?
Thanks in advance

07-12-2008, 07:32 AM
what are the specs for the sub?
what are the maximum sizes the enclosure can be built to?

01 S 10
07-12-2008, 07:46 AM
www.reaudio.com << has a box builder program you can use for free, just need your max outer dimensions.

07-12-2008, 02:07 PM
Thanks for the replies guys

07-13-2008, 03:44 AM
If i am looking for the best SQL then what should the port be tuned to 32 or33 or will 1hz really not be THAT noticeable to human ears? Anyways that reaudio.com site was a great help and virtually builds the box for u. I plan to make the box an L ported box with dimensions W=35" H=15" and D=11". Internal Volume is going to be around 2.0-2.1Cubes with all displacements taken account for. The port is going to be 1.75" wide and 10" long which makes the freq about 33.5hz. Should i lower the Freq by increasing the size of the port length or making the port less wide? or is the freq fine for a decent combo of SQ and SPL? Also i have one question that is prob answered in one of the many amazing stickies....But when i construct the box i use screws obviously but i should just put wood glue along the seams too? or between the pieces of wood then glue them together then screw them together? or after it is contructed am i supposed to seal off the box except for the port with silicon?
Thanks for all the great help guys
Keep the replies coming;)

07-13-2008, 08:10 AM
changing the freq. by 1 Hz will not be heard by your ear and you can't get both a spl and sq enclosure. it has to be one or the other. what i think you are looking for is something that is more of a pounder, something with good bass. a spl enclosure will be basically a one note wonder. it's designed around a certain freq to get the highest db reading in comps. you must put glue between the pieces of wood and i would suggest that you spread it nicely with your finger as well so that you cover the whole surface. when you have only one panel left to put on you must seal every corner or edge even where the port is. think of it in a manner that if you filled it with water it mustn't leak anywhere. silicon will do for this. with the last panel put silicon on all the edges and then screw it down. send me the specs of the sub and i'll put it into winisd and send you a pic of the freq curve with the box you have designed with re. you'll get a better understanding of what you will hear in the freq. range by looking at the graph.

07-14-2008, 01:06 AM

Theres the link to the manual for the sub and it will have all the specs u need its a SWR-1242D btw because they have more than one sub in that manual....
So what do u recommend i tune the box to if i want semi responsive bass(like punch) i mean i know its not gonna be like a sealed box but i would prefer it to be LOUD but not deafening and i want it to be kinda good for punchy bass too

07-14-2008, 10:08 PM
Ascitiesburn, I have the same situation as you. Same sub and I want the same size box with around 33hz. I used RA also, did you calculate the box then subtract the sub displacement after you did all the calculations?

I noticed there is no spot to plug in the subwoofer displacement. I personally did all my calculations then subtracted the sub displacement. After that I made the port longer to compensate for the sub displacement, which according to alpine is .071 so I added .5 in'' to the port length.