how to determine best box size?

[SSS 18734]

well im looking to build a new box for the 2000SPL's. My current one is ****** and is tuned to 48hz . **** pioneer specs.

1. I want my new one to be tuned pretty low, say somewhere around 32-35hz. My question is, how do I determine the ideal box size for my specific subwoofer for that specific tuning frequency? Basically, I want the loudest possible box for that tuning frequency. I have a practically unlimited amout of space to work with... but I want to be able to at least pick the box up .
b.t.w. I would prefer multiple tube ports over a slot port design.

2. also, I have Bass Box Pro 6 and I would like to design my own box but im having a lot of trouble figuring out the program. Im going to sit down with it tonight and try to figure it out. Is there like an online tutorial for it or anything?

[kuijo]

Figure out the QTC you want. and then that'll give you some of your measurments. Jmac knows the formula, i don't off the top of my head. you could wait till he responds.

[Beat_Dominator]

In a ported enclusure the ports alone determine the tuning frequency for a given box size. So all you really need is to pick a volume, and then determine the port length for your 32-35hz tune.

As an example, let's say you have 2 generic 12"s, I would say 3-3.5 cu. ft. is a safe volume for the pair..... then I would determine the port lengths from there. Maybe take pioneers volume but change the port spec.? It's up to you.

[DBfan187]

2cF 33Hz

[SSS 18734]

Beat_Dominator - well its a little more complicated than that. If I have say, a 1 cu.ft. box tuned to 35hz, it will perform quite differently from a box 5 cu.ft. in size, right? Of course it will. So basically, since I dont have a lot of space restrictions, I want to figure out the best volume/tuning combination for my particular sub, and be able to get these subs to play nice and low while still maintaining a lot of SPL. a flat response curve is not a concern at all, a large peak is fine with me.

DBfan - how did you get that, if you mind me asking?

[DBfan187]

lucky guess

[SSS 18734]

lucky guess

lol I dont want to just guess... .
Any sites/threads you know of that has good information on box design?

[Beat_Dominator]

Correct, so if you want SPL out of it, you'll want to go as large as you can for the power that you're giving the subs. If you have too much power or too big a box, the volume of air inside the box will not be able to prevent over excursion. You need the air inside to act as a spring to help control the cone's movement. You don't want to free-air these things with 3kW

[kuijo]

Fine, i didn't want to help you anyway.

[DBfan187]

lol I dont want to just guess... .
Any sites/threads you know of that has good information on box design?

dude, I used BB6P.

[SSS 18734]

dude, I used BB6P.

well thats different than just a "lucky gues"

how would I use BBP6 to figure out the best size/frequency for my drivers? not that im doubting your measurements, but I want to be able to do it on my own also.

[DBfan187]

1st you have to get the updates.
Then read the on screen manual.

[PowerNaudio]

i use winISD, its way simpler then BBP, i have gotten very very! good results with it. just input the sub T/S parameters for that particular sub, then just have fun with it.

[SSS 18734]

where can I get a copy of WinISD? i cant find it on bearshare

and yes BBP6 is really complicated for purposes.

[PowerNaudio]

where can I get a copy of WinISD? i cant find it on bearshare

and yes BBP6 is really complicated for purposes.

baaam

and here for more info