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abrhino
04-16-2010, 05:17 AM
im shooting for a Tunable port for my DC LV5.. i need help with my design.. its gonna be sub up/ port back around 3.2 after wood/port/bracing displacement

External
36w X 14t X 17d

Internal
34.5w X 12.5t X 15.5d = 3.87cuft minus .68cuft port disp = 3.19cuft

Im going to divide the port into 2 horizontal sections using sanded and rounded .75MDF. directly in half so the port height will be 11.75H or 2 5.87h X 6w sections.. port displacement is .68cuft

If my calculations are right tuning will change if i plug the bottom port..

Unplugged
11.75h X 6w X 17.3L = 45hz

Plugged
5.87h X 6w X 17.3L = 33-34Hz


Will the 35.3sqin of port work for daily on the DC LV5? unplugged it is 70.6 SQin of port

CoilBurner
04-16-2010, 05:48 AM
Your daily plugged low tune port needs more area. Do interchangeable ports. Much easier

abrhino
04-16-2010, 06:58 AM
its 11sqin per cube.. how is it much easier? i dont understand interchangable ports very well

abrhino
04-16-2010, 07:17 AM
what if i change the port

5.87t X 7w X 21L = 33hz and 41sqin port. nearly 14sqin port per cuft.

port displacement is 1cuft 3.87-1= 2.87cuft

or

5.87t X 8w X 24.3L = 33hz and 46.4sqin port. 18.2 sqin port per cuft

port disp is 1.32. 3.87-1.32 = 2.55cuft

Fuknmovin
04-16-2010, 09:19 AM
I would try to stay as close to the DD calc as possible and that is 16" per CuFt. But I think your 14"er will work good...

abrhino
04-16-2010, 09:32 AM
yeah imma go with the 14sqin. unless sumthin comes up

abrhino
04-16-2010, 12:20 PM
bump for opinions?

bubbagumper6
04-16-2010, 12:27 PM
Did you actually calculate the tuning using 2 ports or did you just calculate it for one then plan on dividing the port? Because you can't just divide a port and keep the same length, it will affect the tuning. Also, for when the one is plugged, did you take into account the fact that one of your ports is now part of the net volume? That also will affect the tuning.

I think this is more complicated than you think...interchangeable ports would be better.

Fuknmovin
04-16-2010, 12:29 PM
Good point....

abrhino
04-16-2010, 01:01 PM
yes, i accounted the port displacement into both of my designs.. the one with 7in port width is 2.87 cuft after port displacement.. and YES i calculated both ports in the12volt port calculator..

in a 36w X 14t x 17d box it is 3.87cuft before port displacement

port (account for .75 brace/separator) 11.75t X 7w X 21L = 45hz
half the port height (bc its plugged) 5.88t X 7w X 21L = 33hz

thats what my calculations came up with. Subwoofer Enclosure Calculators, Fraction to Decimal, Parallel, Series, Port Length and Volume Calculators (http://www.the12volt.com/caraudio/boxcalcs.asp#porsq)

abrhino
04-16-2010, 01:03 PM
if thats incorrect, plz help me understand. i crunched numbers for an hour comin up with this

bubbagumper6
04-16-2010, 01:54 PM
yes, i accounted the port displacement into both of my designs.. the one with 7in port width is 2.87 cuft after port displacement.. and YES i calculated both ports in the12volt port calculator..

in a 36w X 14t x 17d box it is 3.87cuft before port displacement

port (account for .75 brace/separator) 11.75t X 7w X 21L = 45hz
half the port height (bc its plugged) 5.88t X 7w X 21L = 33hz

thats what my calculations came up with. Subwoofer Enclosure Calculators, Fraction to Decimal, Parallel, Series, Port Length and Volume Calculators (http://www.the12volt.com/caraudio/boxcalcs.asp#porsq)

That's not what I'm talking about. All your calculations for when you have both ports open say that the port is 11.75H, which it's not, you have two ports that equal 11.75H. You can't just take a port and divide the height in half, it will affect the tuning. And I know for a fact you didn't do this because the12volt calculators don't allow you to enter that you have more than one port.

RAM_Designs
04-16-2010, 06:40 PM
Use the carstereo.com calc, you can enter as many ports as you'd like. :D

abrhino
04-17-2010, 05:36 AM
That's not what I'm talking about. All your calculations for when you have both ports open say that the port is 11.75H, which it's not, you have two ports that equal 11.75H. You can't just take a port and divide the height in half, it will affect the tuning. And I know for a fact you didn't do this because the12volt calculators don't allow you to enter that you have more than one port.

you're right. thanks


Use the carstereo.com calc, you can enter as many ports as you'd like. :D

will do man, thank you

abrhino
04-17-2010, 05:54 AM
why is the12volt and carstereo.com port calculators so far off? I pluged in my current box on the12v and it it was 3hz off of carstereo's calculations

current box

is 4.99cuft before port displacement.. port is 14.5h X 5.5w x 16.75d which equals 40hz on Carstereo and 43hz on 12v

abrhino
04-17-2010, 06:03 AM
on carstereo.com, if i plug in

2 Ports
5.88t X 6.5w @ 45hz = 17.93in Port length

1 Port
5.88t X 6.5 @ 32hz = 17.6in port length

abrhino
04-17-2010, 07:12 PM
http://i177.photobucket.com/albums/w217/aprildawnwalker/dave.jpg

this is how im trying to do mine.. this was built locally by a shop who has since went out of business. with 1 port plugged, it sounded great and low daily.. pull the plug out and it meters awesome, i saw that setup do 149 legal and peak at 48hz in an Explorer.. it has never metered below a 148

RAM_Designs
04-17-2010, 07:24 PM
why is the12volt and carstereo.com port calculators so far off? I pluged in my current box on the12v and it it was 3hz off of carstereo's calculations

current box

is 4.99cuft before port displacement.. port is 14.5h X 5.5w x 16.75d which equals 40hz on Carstereo and 43hz on 12v

I actually came up with ~44hz with the carstereo.com calc, considering that you'll have 4.15ft^3 after port displacement. This is also assuming you have already taken into account the sub's displacement. If not, tuning will go up another 1hz.

abrhino
04-17-2010, 08:16 PM
so my current box isnt tuned anywhere near 40hz?

is my 2port design close to 45 and 33hz?

RAM_Designs
04-17-2010, 08:21 PM
is my 2port design close to 45 and 33hz?

Depends what box volume you want to use. You also have to take into account that when you plug that port, it's now acting as part of the box and adding volume to the box.

abrhino
04-18-2010, 12:37 AM
I want my box volume 2.5-3.5 after displacement. not really picky. i think my 2port design falls into this catagory..
unless i am not doin sumthin right.. i can "show my work" if i need to. so you correct my messups

36w X 14t X 17d external measurements = 34.5w X12.5t X 15.5d = 6684.375.
6684.375/1728 = 3.87 cuft

i'll be using a port separator that .75. the port height will be 12.5-.75= 11.75in . two ports so 11.75/2= 5.88ea port height

port area 5.88t X 6.5w X17.75L =678.405 /1728 = 0.39 port displacement per port .39x2 = .78cuft of displacement

3.87- .78= 3.09cuft after port displacement

abrhino
04-18-2010, 03:24 PM
bump

abrhino
04-18-2010, 03:43 PM
i used this PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES

calculate your vent length

square port- YES slot port-YES

number of ports- 2
enclosure volume- 3.87
desired frequency- 45hz
port height- 5.87
port width- 6.5
LENGTH- 17.89

number of ports- 1
enclosure volume- 3.87
desired frequency- 32hz
port height- 5.87
port width- 6.5
LENGTH- 17.6

i figured it as plugging one port removes the port, and tried to find a common port length, which was 17.6in and 17.89. i figured tuning wouldnt wouldnt be affected to badly if i used an average of 17.75in length

bubbagumper6
04-18-2010, 03:58 PM
You can't sue the same enclosure volume for both calculations because when you plug the end of one of the ports, the volume that that port normally occupies, now becomes part of the net volume.

the Answer
04-18-2010, 05:17 PM
use winISD

RAM_Designs
04-18-2010, 05:24 PM
Have you thought about doing two ports on separate sides, then plugging one for them? It's a good deal easier to work the numbers that way.

abrhino
04-18-2010, 10:23 PM
Have you thought about doing two ports on separate sides, then plugging one for them? It's a good deal easier to work the numbers that way.

i thought it but i was scared that 2 separate ports would take up too much volume


You can't sue the same enclosure volume for both calculations because when you plug the end of one of the ports, the volume that that port normally occupies, now becomes part of the net volume.

how drastic will it affect tuning and volume. any chance that it will be negligable and little effect?


use winISD

i have no idea how, but i will tinker with it

abrhino
04-18-2010, 10:32 PM
im not super worried about the box volume. the DC will work fine in 2-3.5cuft. i just want the Tuning as close to 43-46hz and 32-34hz as possible

RAM_Designs
04-18-2010, 10:44 PM
i thought it but i was scared that 2 separate ports would take up too much volume


Maybe a few tenths more, but you have plenty of room in that magnum anyways.

abrhino
04-18-2010, 11:05 PM
true, i have hella space back there

whats worst case scenerio, if i do the 2 ports 5.88t X 6.5w X 17.75L ? im sure box volume will be fine , but how drastically off are my calculations? its not like i HAVE to be pinpoint accurate, but i'd like to be at least 32-35hz 42-46hz range

mylows10
04-18-2010, 11:13 PM
id try aeros ,much easier

abrhino
04-19-2010, 01:18 AM
i'd have to buy aero's. if this works it'll be much cheaper and easier to plug

abrhino
04-19-2010, 10:03 AM
bump?

abrhino
04-19-2010, 11:21 PM
bump

the Answer
04-20-2010, 01:57 PM
i have no idea how, but i will tinker with it

the enclosure section has a sticky that will show u how to use it

jdawg
04-20-2010, 02:33 PM
I really think aeros would be alot easier to do it with, just do like 3 or 4 then plug a couple of them, or iif they dont end up right its so much easier to either cut them down or put in a new pipe

abrhino
04-21-2010, 01:46 AM
how would i get the tuning calculated? if I could do that, then i could do dual slots easier/cheaper

abrhino
04-22-2010, 10:56 PM
bump for more help other than, Buy aeros

Jaredturp
04-23-2010, 12:30 AM
Anyone able to make port area reducers for Aero's? I want to get 2 of that one guy's 8" aero's! But that's not what I want tuning wise for daily.

abrhino
04-23-2010, 10:04 PM
that does not help my thread

abrhino
04-25-2010, 04:22 AM
does anyone know how 2 calculate dual port length?

RAM_Designs
04-25-2010, 10:52 AM
does anyone know how 2 calculate dual port length?

carstereo.com has a calculator that can do multiple ports.

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

bubbagumper6
04-25-2010, 10:58 AM
Look dude, you obviously don't have near enough experience or the skills necessary to design an enclosure as complicated as this. Why don't you do yourself a favor and just pay the $5 it costs to get a design from one of the vets on here?

Jaredturp
04-25-2010, 12:12 PM
I agree ^^

abrhino
05-03-2010, 07:59 AM
i got it designed just needed a math double check

basshedz06
05-03-2010, 08:42 PM
the best method homeslice i can possiable tell you to do is get with someone that has a termlab an test that ***** for 6hrs or more an see where ya at cause when it all boils down to it ain't nothing more accurate than that man. no disrespect on what you doing an all that but that is the simpliest answer i can give man is test it cause it sounds to me that you wanna burp an do a loud number while staying musical. it is possiable lol in a tahoe or burban or explorar only lol but burp game is for spl cars man what you an i like to day like beating our music an doing a decent number well thats gonna take some work an i hope your in for the ride man cause its gonna take alot of building if ya wanna get loud on meter. now if ya just wanna ride an beat an impress all the girls an kids then build that bit 6cubes tuned to like 28hz an bang like that.