I am planning on building a 4ft^3 for my BL 15. I was just wandering what size my slot port should be (Length, height and depth) if i want it tuned to 33hertz?

heres a link you can play around on and make a really good box to what you like it helped me alot with my first box

RE Enclosure Calculator

You will need roughly 72in^2 of port!

heres a link you can play around on and make a really good box to what you like it helped me alot with my first box

RE Enclosure Calculator

That thing is HORRIBLY inaccurate, please don't recommend people use it.

ok thank you i didn't know that it was i will not recomend it anymore, should i make a new box for my 12" btl then or is it going to be ok in the box i made the dimetions are 28" long 20" deep 15" high 3.75" port and the port is 16.25 deep and 16" to make it an L shape ?

Yea i was recomended to it and without knowing made the box EXACTLY as it was stated... lets just say its not as loud as the PREFAB box i had before.... just a personal experience

ok thank you i didn't know that it was i will not recomend it anymore, should i make a new box for my 12" btl then or is it going to be ok in the box i made the dimetions are 28" long 20" deep 15" high 3.75" port and the port is 16.25 deep and 16" to make it an L shape ?

What did you calculate for a tuning frequency?

the site told me that it was tuned to 34.9.... hrtz i used it b/c i have no clue how to calculate it myself

You look to be a little large on your enclosure and tuning is in the 36-37 hz range. I have no idea what you have for bracing.

With no bracing at 2.5ft^3 and tuned to 35hz you will need a total port length of 37".

i have no braceing and port lenght would be 32.25 would braceing help at all ?

i have no braceing and port lenght would be 32.25 would braceing help at all ?

Bracing will help take up internal volume, but will end up tuning your enclosure a higher.

ok thank you for your help i think i'm just going to make a new box

do you know where to find information on how to tune a box propperly ?

I am planning on building a 4ft^3 for my BL 15. I was just wandering what size my slot port should be (Length, height and depth) if i want it tuned to 33hertz?

We will need box dimensions for a slot port or you can go Precision Port (Aero).

do you know where to find information on how to tune a box propperly ?

PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES

PORT DESIGN FORMULAs for SUB WOOFER ENCLOSUREs

Some good reading on the second link.

Good luck!

do you know where to find information on how to tune a box propperly ?

Subwoofer Enclosure Calculators, Fraction to Decimal, Parallel, Series, Port Length and Volume Calculators

thank you very much

one other ? when calculating the ft3 do you include the port or no ?

it doesn't spesify in the calculator

Edited May 26, 201015 yr by icy_chris

So what is the problem with the RE audio calculator? I wish it had more options, but i dont see what the problem with it is?

So what is the problem with the RE audio calculator? I wish it had more options, but i dont see what the problem with it is?

Doesn't account for woofer displacement or bracing! One thing I don't like is the fact when you widen the port the further it brings it away from the back wall.

So what is the problem with the RE audio calculator? I wish it had more options, but i don't see what the problem with it is?

Biggest problem I see is it does not subtract driver displacement, so your actual tuning will be higher than what the RE program says.

one other ? when calculating the ft3 do you include the port or no ?

it doesn't spesify in the calculator

Always account for port displacement when figuring cubic feet!

So what is the problem with the RE audio calculator? I wish it had more options, but i dont see what the problem with it is?

It calculates volume wrong so that throws off tuning, another problem I've seen with it is you can make the port to long for the box. ie you can make the port end up being 2.5" from the side wall of the box when your port is 3.5" wide, which will mess with tuning calculations.

So what is the problem with the RE audio calculator? I wish it had more options, but i dont see what the problem with it is?

It calculates volume wrong so that throws off tuning, another problem I've seen with it is you can make the port to long for the box. ie you can make the port end up being 2.5" from the side wall of the box when your port is 3.5" wide, which will mess with tuning calculations.

What do you guys think about the box/port calculator on the site 12volt.com ?

Just noticed that Johnecon2001 had the link to 12volt.com... That site saved my ass acouple of times, its great......I know your port should be over 2" wide. Thats what I maid my at and you can hear port noise. Not inside the car but when I pop the trunk you can hear it.