check out first my cusom sub box design

[js09 10+ year member]

Using 4" ports is ridiculous for my setup because they would have to be 21" long each (lol).

also, sites like these:

http://www.psp-inc.com/psp-inc.com/cgi-bin/port_length_calculator.cgi

http://www.carstereo.com/help/Articles.cfm?id=31

do they already take into account the displacement of the ports?

i hope so, because if not..

to find volume of box, you need port displacement

to find port displacement (more specifically port length) you need volume of box

so it's a never ending equation which then makes those sites useless. but i'm guessing they take into account the port displacement in the calculations.

anything else i'm forgetting? 13.25" is the tallest I can go so don't ask about that hehe.

from my understanding this should be pretty close to perfect for what i'm doing. if not, let me know! thanks.

Click to read more...

 

[js09 10+ year member]

the title should read 'custom', not 'cusom'

 

[snoopdan 5,000+ posts]

without just looking at the calculations, the box is pretty proportional to the sub and vents to me. I think thats a great start for you. But having a trunk car is a pain in the azz sometimes and you get little gain in certain situations off of the trunk.

 

[SplChoice- 10+ year member]

just go slot port man ur hardly getting any port area outta those.

 

[BJ The Man 10+ year member]

just go slot port man ur hardly getting any port area outta those.

slot port is an awesome idea. more port area and if you ask me more fun to build. (dont know why)

subwoofertools.com

reaudio.com (re enclosure calc)

both of those are good

your design does look good though. i like it.

BJ

 

[snoopdan 5,000+ posts]

slot port is an awesome idea. more port area and if you ask me more fun to build. (dont know why)
subwoofertools.com

reaudio.com (re enclosure calc)

both of those are good

your design does look good though. i like it.

BJ

he may not have the space for a slot box in that trunk... plus, its a CVR, it doesnt exactly have 40 mm xmax or something so its not going to be some uberwoofer install. His box design should work just fine.

 

[js09 10+ year member]

thanks guys

however i thought having two 3" ports will be just as good (or better) than a slotted port box? it should technically be the same though, right?

 

[js09 10+ year member]

well i do have room in my trunk for a slotted box, i just picked the round ports because it looks cooler and maybe easier to build

 

[snoopdan 5,000+ posts]

well i do have room in my trunk for a slotted box, i just picked the round ports because it looks cooler and maybe easier to build

well, it is easier to build...kinda just plug and play and not have to cut extra peices for the vent. If this is your first box, then aeroports are a good start.

good luck

 

[js09 10+ year member]

well, it is easier to build...kinda just plug and play and not have to cut extra peices for the vent. If this is your first box, then aeroports are a good start.
good luck

I will be using 3" PVC pipe, unless I can pick something up locally that's better, but I don't know of anything.

 

[snoopdan 5,000+ posts]

I will be using 3" PVC pipe, unless I can pick something up locally that's better, but I don't know of anything.

why dont you just use some precision port 4" aero's and adjust the measurements? would look alot cleaner and it will fit nicer.

 

[js09 10+ year member]

anyone figure out yet if what i said is true/false?

also, sites like these:http://www.psp-inc.com/psp-inc.com/cgi-bin/port_length_calculator.cgi

http://www.carstereo.com/help/Articles.cfm?id=31

do they already take into account the displacement of the ports?

i hope so, because if not..

to find volume of box, you need port displacement

to find port displacement (more specifically port length) you need volume of box

so it's a never ending equation which then makes those sites useless. but i'm guessing they take into account the port displacement in the calculations.

 

[bass_lover1 10+ year member]

do they already take into account the displacement of the ports?

i hope so, because if not..

to find volume of box, you need port displacement

to find port displacement (more specifically port length) you need volume of box

so it's a never ending equation which then makes those sites useless. but i'm guessing they take into account the port displacement in the calculations.

anything else i'm forgetting? 13.25" is the tallest I can go so don't ask about that hehe.

from my understanding this should be pretty close to perfect for what i'm doing. if not, let me know! thanks.

Usually not no.

Use the equation to find the tuning frequency you desire, also use the box size that you want. Say you want 2.5 cubic feet at 33 hz and a specific port length and area. What you're trying to do is have the net internal box volume be 2.5 cubic feet, so you build the box larger to accommodate the port displacement and driver displacement.