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View Full Version : new "in progress" ported mag box *pics*



amedeuce
03-06-2005, 05:32 AM
This is my attempt to port my magnum. After sub, port and bracing the enclusure will be around 2 cubes. It should be tuned to 29 hz when all said and done. I will be using a round port. If my calculations are correct, the port should be 3 inch diameter by about 9 inches.
Dimensions are on the pic, what do ya think??

Stack o Wood

http://gallery.caraudio.com/vg/1/1/0/0/4/DSCF0343.JPG

dry fit

http://gallery.caraudio.com/vg/1/1/0/0/4/DSCF0333.JPG

dry fit #2

http://gallery.caraudio.com/vg/1/1/0/0/4/DSCF0334.JPG

amedeuce
03-06-2005, 05:34 AM
Oh the box design is so it will fit my truck...

supa_c
03-06-2005, 05:35 AM
better be a flanged port

Acidburn
03-06-2005, 05:35 AM
are you sure a signle 3" port is big enough?

amedeuce
03-06-2005, 05:35 AM
better be a flanged port
what do ya mean??

amedeuce
03-06-2005, 05:36 AM
are you sure a signle 3" port is big enough?
I thought till you said something

Acidburn
03-06-2005, 05:36 AM
i think a Mag wants more than that

supa_c
03-06-2005, 05:36 AM
www.psp-inc.com
;)
1 3" port isnt enough for a mag

amedeuce
03-06-2005, 05:38 AM
i think a Mag wants more than that
2 cubes net tuned to 29hz is what was recommended by SI..

Acidburn
03-06-2005, 05:38 AM
i mean port area

supa_c
03-06-2005, 05:39 AM
you can buy them from parts express like i did
dual 3's would be better than 1 4"

amedeuce
03-06-2005, 05:39 AM
4 inch by about 17 in???

supa_c
03-06-2005, 05:40 AM
buy
2 3" psp ports

amedeuce
03-06-2005, 05:40 AM
you can buy them from parts express like i did
dual 3's would be better than 1 4"
Man you reply fast. Ok (2) 3" ports??

Acidburn
03-06-2005, 05:40 AM
remember, having a larger/longer port takes up more volume inside the box which changes the tuning freq of the port

amedeuce
03-06-2005, 05:41 AM
so how long should each be??

amedeuce
03-06-2005, 05:41 AM
remember, having a larger/longer port takes up more volume inside the box which changes the tuning freq of the port
I have a little extra, plus I over estimated for bracing...

supa_c
03-06-2005, 05:44 AM
Man you reply fast. Ok (2) 3" ports??
crappeer doodles
it needs more than 2 3's
more like 2 4's

amedeuce
03-06-2005, 05:44 AM
according to a port cal. (2) 3 inch ports = around 20 inches. Is that ten each =20 inch or 20 each??

supa_c
03-06-2005, 05:45 AM
www.psp-inc.com
use the port calc generator

amedeuce
03-06-2005, 05:45 AM
crappeer doodles
it needs more than 2 3's
more like 2 4's
Ok

Acidburn
03-06-2005, 05:45 AM
i dont even know if 2 4"ers is enough, thats only like 25 sq inches

supa_c
03-06-2005, 05:46 AM
its time for bed man

Acidburn
03-06-2005, 05:47 AM
g'night

amedeuce
03-06-2005, 05:48 AM
well crap, I can make this work, good thing it's only dry fitted. So (2) 4inchers is or isnt enough?

supa_c
03-06-2005, 05:48 AM
dunno...wait for a couple house for the east coast boys to show up
later man

amedeuce
03-06-2005, 05:49 AM
dunno...wait for a couple house for the east coast boys to show up
later man
thanks, see ya

saywhat?
03-06-2005, 06:56 AM
if u go sealed, its 3.1 cubes, with a port......im gunna figure this out, give me a little,how much is driver displacement?

if u go 2 4 inch ports, its 23.05 straight length, and 24.05 flared end (both ends flared at the end of a 23.05 makes it 24.05.

now each port would take about .12 cubic foot, so look at .3 cubic foot after all ports are sunk in, maybe more like.2 actually, cuz the end of the port is port outside, so maybe it would end up something like .2, all this is for 29 hrz. i dunno if it will help, i dont know how much air a magnum displaces so.

monte_carlo97
03-06-2005, 09:40 AM
why not make a slot port instead of using circurrlar ports.

amedeuce
03-06-2005, 12:13 PM
the mag displaces .1

amedeuce
03-06-2005, 12:18 PM
why not make a slot port instead of using circurrlar ports.
cause I figured they displace more area and I'm trying to conserve space. but now it doesnt look that way

GCAdidas13
03-06-2005, 12:30 PM
cause I figured they displace more area and I'm trying to conserve space. but now it doesnt look that way

conserve space and give like 5 people on the forum a headache :)

it ***** that you've already cut the wood, else you'd be able to go a couple inches bigger in a couple directions (That adds a lot of volume).

Let me see what I can do. Those are internal dimensions on the picture?

amedeuce
03-06-2005, 12:40 PM
conserve space and give like 5 people on the forum a headache :)

it ***** that you've already cut the wood, else you'd be able to go a couple inches bigger in a couple directions (That adds a lot of volume).

Let me see what I can do. Those are internal dimensions on the picture?
yea I know. those are external directions.

amedeuce
03-06-2005, 12:47 PM
If it helps, I can put the sub firing up, or out the side.

GCAdidas13
03-06-2005, 01:08 PM
well you wanted the port to be on the side that you put on one of the first pics... why don't you build a port in on the bottom of that same side?

amedeuce
03-06-2005, 02:03 PM
well you wanted the port to be on the side that you put on one of the first pics... why don't you build a port in on the bottom of that same side?
I assume you mean a slot port right?

amedeuce
03-06-2005, 02:11 PM
Maybe I'm using bad calculators or I dont know how to use them properly, But for a slot port. How high and deep should I make it. I so confused. The calc. Shows if I want a 4x4 square port it will be only 20 inches long

amedeuce
03-06-2005, 02:16 PM
Why is it the bigger round the port the longer the length has to be.
And I'm assuming that even though you can use a smaller diameter and shorter length to get the desired tuning that it would sound like crap...Right??

amedeuce
03-06-2005, 02:21 PM
Volume of Box in Cubic Feet: 2
Tuning frequency 29
Port diameter 4
Number of Ports 1
Straight Length Port required 17.21
Flare Length Port required 18.21


this is what I get in the calculator provided in this topic.. Now I understand that this would be bad to use for some reason, but why?

amedeuce
03-06-2005, 02:22 PM
:smash:

GCAdidas13
03-06-2005, 02:50 PM
Volume of Box in Cubic Feet: 2
Tuning frequency 29
Port diameter 4
Number of Ports 1
Straight Length Port required 17.21
Flare Length Port required 18.21


this is what I get in the calculator provided in this topic.. Now I understand that this would be bad to use for some reason, but why?

When designing boxes for subs, the size of the port is important. For instance, I just threw some Koda 8's into my old bookshelf boxes of volume .66 cubes and has a 2" diameter port with 3" length, and the improved bass and xmax induced a heck of a lot of port noise.

Well you'd think you would want as much port area as possible right? Wrong. The more port area you have, the longer the port has to be to achieve the same tuning. This also takes up more room, so if space is an issue, that will cause problems.

You have to find a happy medium. You need a big port, but not so big that your port takes up 2 cubic feet of your box.

As far as I know magnums are pretty beastly. I'd say you would want around 40 square inches of port, perhaps? What size is the sub?

amedeuce
03-06-2005, 03:09 PM
It's a 12. It's the claw basket

Vented = 1.5 cubic feet tuned to 32 Hz, or 2.0 cubic feet tuned to 29 Hz.

The enclosure volumes above are after port and driver displacement.

T/S parameters:

Nominal Impedance: 2 Ohms per coil
Re: 3.6 Ohms (coils in series)
Fs: 32 Hz
Sd: 0.05 sqM
BL: 18.6 TM
SPL: 88.4 dB (1W/1M)
Qms: 4.05
Qes: .41
Qts: .37
Vas: 38.5 liters
Mms: 175.7 g
Mmd: 169.2 g
Cms: 108.5 uM/N
no: .43%
Xmax: 24 mm
Mechanical p-p: 2.6
Power Handling: 900 watts RMS.

Mounting information:

11 1/8'th cutout diameter
6.75" mounting depth

GCAdidas13
03-06-2005, 03:15 PM
Which way does the 15" by 16" side face, when all is said and done and installed?

amedeuce
03-06-2005, 03:17 PM
that side will face the back of the front passanger seat with about 6 inches of clearance

GCAdidas13
03-06-2005, 03:22 PM
alrighty. I get a total of (exactly) 2.2079 cubes if you go sealed at this point (0.75" mdf)

now, if you put the edge of the sub on the left edge of the piece, and the sub is (to give a little leyway) 12.5" diameter, this leaves you with 3.5" to work a port in there. The theres the other piece of wood so that leaves a 2.75" wide port. Port would be 2.75" wide by 13.5" tall...

and then the port would have to be 47" long. Scrap that idea.

amedeuce
03-06-2005, 03:24 PM
Would it help if I put the sub facing up?

GCAdidas13
03-06-2005, 03:28 PM
Probably not, to tell you the truth. Either way it will be difficult to maintain 2 cubes tuned to 29hz if you already have pieces cut for 2.2 gross cubes, IMO.

amedeuce
03-06-2005, 03:32 PM
what about changing the tuning.

amedeuce
03-06-2005, 03:33 PM
or going with the other recommended enclosure 1.5 tuned to 32hz?

GCAdidas13
03-06-2005, 03:34 PM
i'll see what i can do with it

GCAdidas13
03-06-2005, 03:45 PM
attention people who would know

is 25 square inches of port enough for a magnum

if yes, i have a solution
if not, i can not find a solution

GCAdidas13
03-06-2005, 03:49 PM
if 25 square inches is enough for a magnum, i can get ~1.5 cubes tuned to ~30hz. build the sub into the bottom of the 15x16" piece, and the port is 1.75 tall and 14.5" wide across the top of that same piece, and 25.75" long. the port will wrap across that top corner and down the back of the box, but no wood will be needed to build there.

amedeuce
03-06-2005, 03:50 PM
hopefully someone will know or I guess I'll scrap the whole thing and try to salvage and materials I can.

amedeuce
03-06-2005, 03:50 PM
if 25 square inches is enough for a magnum, i can get ~1.5 cubes tuned to ~30hz. build the sub into the bottom of the 15x16" piece, and the port is 1.75 tall and 14.5" wide across the top of that same piece, and 27.25" long.
maybe that will work

amedeuce
03-06-2005, 03:51 PM
if 25 square inches is enough for a magnum, i can get ~1.5 cubes tuned to ~30hz. build the sub into the bottom of the 15x16" piece, and the port is 1.75 tall and 14.5" wide across the top of that same piece, and 27.25" long.
that will also be simple to do.

GCAdidas13
03-06-2005, 04:07 PM
1.65 cubes tuned to 32 with 25 sqin of port area and a 33.75" long port to house a magnum 12" subwoofer:

http://img166.exs.cx/img166/105/untitled9av.jpg

make sure the port is 1.75" wide the entire way down, and sand down all the corners to a nice round goodness inside the box to eliminate port noise. if you do all that and there's still port noise (you'll know it when you hear it) you will have to scrap the box and start over.

amedeuce
03-06-2005, 04:20 PM
man you are awsome

amedeuce
03-06-2005, 04:29 PM
I'll work on it later. If I do decide to scrap it, keeping in mind the same design, how would I make 2 cubes tuned to 29hz. I have room to build taller and a little deeper, but not wider. Thanks again

GCAdidas13
03-06-2005, 04:35 PM
It would be the same design, but taller. If you have to rebuild, send me a PM and I'll do another design for you. :)

Enjoy

sue bee
03-06-2005, 09:44 PM
some cool dudes around here, nice work