need help with a box design

[knubs]

alright, so basically over the past few months i have been reading non stop about car audio trying to educate myself with the intent of upgrading my system from my one 12" sub to a "real" system. i feel comfortable with my knowledge on most things in car audio now, but one thing that still confuses me is designing a subwoofer box.

i bought my sub today here on the forums; i got a 15" DC xl (m1). it was the exact deal i was looking for but i didnt expect to find it so soon! so now i have about a week to design and build a box. i planned on having more reading time but now its time to do this!

so basically i would love to be able to save time on research. i dont mind reading and learning but trying to do research from the ground up takes a lot of time because it's hard to find the good resources, so if you guys could link me to any of the best resources you can think of that would be awesome. i've done a lot of reading already and have read up on programs like win isd, and i tried using that but couldnt get around the errors... so any links to useful programs are also welcome.

im willing to take whatever help or advice i can get. the more knowledge the better!

and here is just a quick run down of what i will be working with.

2002 mitsubishi lancer es

180 amp after marker alternator

kinetic hc2000 battery

hifonics brz2400 amp

dc 15" xl m1.

i've accepted that my trunk space is going to all be gone so i am going to try and make my trunk look good after the install. for the box i was thinking that i would do about a 5 cubic foot box that is tuned to maybe like 36 hz.

so you guys point me a direction and tell me where to start reading and what will be the most helpful and i will be a happy camper!!

Thanks!

[321slapinbass]

learn by reading. just start reading everyone's topics and posts here in the sub / enclosure section and you will learn alot about boxes fast.

[knubs]

i am reading through everything i can. i am reading thread after thread after thread. i should have signed up here a long time ago. i have been here a lot from google but i never actually browsed the forums and went through thread after thread. i am learning a lot.

and in the end i guess i was hoping that some very knowledgable experienced box builder had written a guide with all their wisdom layed down and broken down or something. i knew i wouldn't be that lucky though. but if there is any sort of guide(s) that break down different aspects of box building i would love to know about it/them. for now i forum surf though.

hopefully in a few few days i will have a sketch up drawing of a box done to post up and let you guys critique.

[john253a]

so what is it you want?

what coil config did you get and you only need 3.5net for that sub

if you want help to design post some measurements of the trunk,

if you have the right coil config to get the most out of the amp

3.5net @37hz 55sq" of port

sub and port forward sealed off

also by doing a higher hz it will assist in keeping the box smaller

[knubs]

the funny thing is, i dont really know what i want. to admit the sad truth i've actually never really heard a good system. i live in a small town and am 20 years old, but no one around here really has systems outside of a 12 or a coulpe 10's from walmart... the best one i've ever heard was 2 12" l7's a few years ago on a boat for a minute.. so i'm not sure exactly what i'm after yet, i predict a few different boxes being built in the next couple months to figure it out though. first thing i want i think is just a box that sounds really good but gets loud and will show me what a DC will do. next i will build a more SPL oriented box.

the woofer i got is exactly what i was looking for. it is a dual 2 ohm so i can wire it in parellel to 1 ohm. and i know the general recommendation from DC is 3.5 feet, but from what i've read (which could be wrong of course) the xl 15" will perform well in anything from a 3-6 cubic foot box and that it does better in a bigger box if you have the room. i wish i could get winisd to work though so i could play around a little... also my other reason for wanting a 5' box is that if i do a 3.5' box then i will be tempted to buy another because i know it will fit!!

and the basic dimmensions i have availabe in my trunk for the box are 12" tall x 31" deep x 36" wide. the sub will have to mount facing up, but i dont know enough about port placement to know if i should have it on the top or the back of the box.

[knubs]

oh, and should i use plywood or mdf? i notice a lot of people using plywood for making boxes for DC's.

[knubs]

alright, i have a couple questions that i need some solid answers to since the answers im finding suck. first, is the tuning of a box soley dependant on the port and box itself? does the particular sub have an affect on box tuning? second, what does changing the size of the box actually do? i keep trying to find a solid answer for that but i am hearing different things all over from google. i've tried using the search feature on this site many times and it just doesnt work. i can literally type in subwoofer and get 0 results...

Thanks again!

[Joe X]

Tuning depends on net internal volume, port area and port length... for all practical matters.. but the frequency response you get out of a box depends on the sub itself, the box and the environment the system is playing in.. but there's another thing that is much harder to factor in which is what your hearing and your brain makes of it.

I guess the only way to know what you want is listening to a lot of systems which you know specs for.

[Maebros]

honestly man since it seems like you know the size and tuning you want so i would recommend downloading torres BTC and sketchup (mttournquist has a sketchup tutorial on here) and start messing around until you get something that looks good. from there post your designs and sketchups on here and we can help you from there

[knubs]

ive made tons of differnt boxes in sketch up and 3d models of my trunk. but im still trying to work out how to design a box.

also ive been messing with the torres calculator a lot, and ive come to realize that it's calculations for volume are wrong. EDIT- must have been glitching or something... i just reinstalled and the calculations are correct now.

this is turning into a frustrating situation. i've never had so much trouble trying to learn something as basic as box building, but between all the bull shit misinformation being yacked out everywhere (not here), the search function here not working, 2 different programs that arent working, and all the crappy unrelated search results by google, this is seeming impossible to actually learn without devoting a year to read every thread on this site. im so happy i found this site though. there are actually knowledgable people on here.