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GrandPrixAlpine
05-30-2011, 01:00 AM
Someone school me. Im want to start building enclosures but i need to learn much more before i start. i know nothing about the tune of the box or anything. i get the port to no port thanks to the stickie up top.
My test run will be with my Memphis M-Class 10" Subs Im going to do a single and a Dual enclosure

2.00 / 38 / 10.5 x 1.25 x 17 those are the specs direct from memphis.

All i get out of that is it needs to be 2.00 Cubic Feet with a port that is 10.5in Front to back by 1.25in witdth by 17 side to side

Kangaroux
05-30-2011, 01:12 AM
instead of doing 2 different enclosures you can make a dual enclosure but do separate chambers, will save you time and money. i suggest downloading sketchup to do designs in as it works great.

alternatively if you hit up ram_designs and have him design a box for you, it comes with a screenshot of the model in sketchup with all measurements. im sure he'd be more than happy to give you a quick rundown of how he went about designing it. its not a hard process, but you need to crunch some numbers repeatedly to get the right results

GrandPrixAlpine
05-30-2011, 01:20 AM
i want to learn how to do it myself. i could easily just have someone else design something for me but id rather do it myself.

GrandPrixAlpine
05-30-2011, 02:18 AM
26525026

This is what i have so far. From the research ive done on here the inside edges should have those slants in them to reduce dead spots right? I went with an L port instead of a S port for simplicity. But how to i get the dimensions of the box so that i get the 34hz per side? Forgot to mention im going to use .5" MDF. Also would there be any benefit to painting the MDF to a Gloss Finish on the inside as im going to on the outside?

Buck
05-30-2011, 03:43 AM
If you need a designer...

But if you have any specific questions you can email me. It's hard to school someone, because when you start explaining you wind up having to explain 10 things to explain that 1 thing.

brandinooooo
05-30-2011, 05:24 AM
26525026

This is what i have so far. From the research ive done on here the inside edges should have those slants in them to reduce dead spots right? I went with an L port instead of a S port for simplicity. But how to i get the dimensions of the box so that i get the 34hz per side? Forgot to mention im going to use .5" MDF. Also would there be any benefit to painting the MDF to a Gloss Finish on the inside as im going to on the outside?

If that one side is tuned to 34 then the same thing on the other side would be at 34.

The slants help the air flow and add some strength to the box

Frito11
05-30-2011, 12:06 PM
26525026

This is what i have so far. From the research ive done on here the inside edges should have those slants in them to reduce dead spots right? I went with an L port instead of a S port for simplicity. But how to i get the dimensions of the box so that i get the 34hz per side? Forgot to mention im going to use .5" MDF. Also would there be any benefit to painting the MDF to a Gloss Finish on the inside as im going to on the outside?

i wouldn't use anything less than 3/4" MDF unless its a really small box or not for a subwoofer. the large surfaces in a box can and will resonate at the right frequency inside the box and when that happens you loose SPL and quality of the bass in general along with it, if it resonates really bad at a certain freq you could destroy the sub as well.

a lot of people also double up the baffle (panel the woofers are on) so its 1.5" thick as well to help eliminate any movement that the subwoofer may induce on it when its playing at high volumes.

i looked up your sub on Memphis's website because that box volume sounded too large for 1 10 and too small for 2 10's if your doing separate chambers for each sub what you want to shoot for is 1.65 cuft / 38 hz according to

http://www.memphiscaraudio.com/documents/Updated%202010%20Enclosure%20Recommendations.pdf

even that is pretty big for a 10 IMO but should sound good. you don't want to build too big a box cu.ft wise internally because if you do the sub will not be able to operate correctly because there is not enough dampening from the box. in my experience its always wise to stay pretty close to or under what the mfg says the maximum size of the box should be. port tuning can be changed to preference really as long as you don't go crazy with it. for a vented 10 38hz is probably as low as you would want to go anyways.

good luck with the design and keep us posted

GrandPrixAlpine
05-30-2011, 01:19 PM
i wouldn't use anything less than 3/4" MDF unless its a really small box or not for a subwoofer. the large surfaces in a box can and will resonate at the right frequency inside the box and when that happens you loose SPL and quality of the bass in general along with it, if it resonates really bad at a certain freq you could destroy the sub as well.

a lot of people also double up the baffle (panel the woofers are on) so its 1.5" thick as well to help eliminate any movement that the subwoofer may induce on it when its playing at high volumes.

i looked up your sub on Memphis's website because that box volume sounded too large for 1 10 and too small for 2 10's if your doing separate chambers for each sub what you want to shoot for is 1.65 cuft / 38 hz according to

http://www.memphiscaraudio.com/documents/Updated%202010%20Enclosure%20Recommendations.pdf

even that is pretty big for a 10 IMO but should sound good. you don't want to build too big a box cu.ft wise internally because if you do the sub will not be able to operate correctly because there is not enough dampening from the box. in my experience its always wise to stay pretty close to or under what the mfg says the maximum size of the box should be. port tuning can be changed to preference really as long as you don't go crazy with it. for a vented 10 38hz is probably as low as you would want to go anyways.

good luck with the design and keep us posted

You missed part of the memphis page, there is a minimum box size and a optimum.

Min Op.
1.65 / 38 / 10.5 x 1.25 x 16.75 2.00 / 34 / 10.5 x 1.25 x 17


No one has really answered my question though. how do i find the lengths to get 2.00 cubic feet and still acheive 34 hz

fasfocus00
05-30-2011, 03:27 PM
You missed part of the memphis page, there is a minimum box size and a optimum.

Min Op.
1.65 / 38 / 10.5 x 1.25 x 16.75 2.00 / 34 / 10.5 x 1.25 x 17


No one has really answered my question though. how do i find the lengths to get 2.00 cubic feet and still acheive 34 hz

someone failed algebra 1?

GrandPrixAlpine
05-30-2011, 05:09 PM
someone failed algebra 1?

as a matter of fact yes i did

fasfocus00
05-30-2011, 05:17 PM
as a matter of fact yes i did

you are going to want someone to design your box for you than. building and/or designing boxes requires proficiency in both algebra 1 and geometry.

GrandPrixAlpine
05-30-2011, 09:08 PM
you are going to want someone to design your box for you than. building and/or designing boxes requires proficiency in both algebra 1 and geometry.

I sure can try though if someone would explain the fourmulas.

GrandPrixAlpine
05-30-2011, 10:33 PM
So using the stickey at the top of the page these are the numbers i got.

Net Vol= 2.00
port area= 10.5 High X 1.25 Wide X 17 Depth
Tuning=34Hz
Desired Width Per Side=20in
Height=10.5 (i think thats right, is it supposed to be the same as the port height?)
Depth=S
Port Length=20.87
Port Displacement= .25362847
Internal Gross Vol=2.55
S=144.47 (doesnt seem right to me)

Frito11
05-30-2011, 11:55 PM
15-MCP10D4

min. 1.10 / 44 / 10.5 x 1 x 16.5
opt. 1.65 / 38 / 10.5 x 1.25 x 16.75


once again straight from memphis' website. this is space per sub ovc

GrandPrixAlpine
05-31-2011, 12:01 AM
once again straight from memphis' website. this is space per sub ovc

I dont know what i found then cause i got mine from there too.

http://www.memphiscaraudio.com/documents/Mid2009%20Consumer%20Enclosure%20Recommendations.p df

Frito11
05-31-2011, 12:06 AM
just to throw out a design having no idea what this is fitting in this is what is recommended by the mfg optimally everything exact except i swapped the square port to a 4" port to make it easier to build correctly.

Box Parts (Optimum Square Prism)
1 Top, 1 Bottom: 12.91 (c) x 19.97 (b) in
0.75 (thick) in
1 Front, 1 Back: 29.88 (a) x 18.47 (d) in
0.75 (thick) in
2 Sides: 29.88 (a) x 12.91 (c) x 0.75 (thick) in

Vent Parts
2 Ducts: 4.25 (ext. diam.), 4 (i.d.) x 10.62 (h) in

Frito11
05-31-2011, 12:11 AM
I dont know what i found then cause i got mine from there too.

http://www.memphiscaraudio.com/documents/Mid2009%20Consumer%20Enclosure%20Recommendations.p df

the PDF your pointing too is older than the one that i used that clearly says "updated" on it.

regardless 2 cubes is way beyond what a ported 10 needs, most 12's don't even need that much air space per sub,they are usually around 1.8-2 max.

while if you graph the performance it may look like the bigger box is flatter and goes lower in practice it just does not work as well and can even cause the power handling to go down on the subwoofer.

i suppose though the real question is what are you looking for in your system?

hard hitting bass?
low bass?
tighter but higher bass?

what kind of music do you listen to most?

GrandPrixAlpine
05-31-2011, 12:22 AM
Alright im going to start all over....

Car: 98 Grand Prix GT
Location:Trunk
Firing: Rear
Subs: 2 Memphis M-Class 10"
Amp: M-Class 2/1 500W
Space:40in Width Available
13in of Height Available
Depth more than needed.
Music:Mostly Hollywood Undead, A little Rap, Lot of Rock, and some country.
I like hard hitting bass. Used to have a Type X running 1000RMS and i just downgraded for a while cause money is running low. so i still want to feel it.

So lets go with your Dimmensions
1.65 / 38 / 10.5 x 1.25 x 16.75

Now explain how to turn that into a Dual Single Chamber Box

Frito11
05-31-2011, 12:39 AM
Box Parts (Square Prism)
1 Top, 1 Bottom: 20.59 (c) x 31.5 (b) in
0.75 (thick) in
1 Front, 1 Back: 11 (a) x 30 (d) in
0.75 (thick) in
2 Sides: 11 (a) x 20.59 (c) x 0.75 (thick) in

Vent Parts
2 Ducts: 4.25 (e), 4 (g) x 10.62 (h) in

external box dims are
31-1/2" wide x 12.5" tall x 20.59" deep

put to woofers on the 31.5 x 12.5 face as i assume that this is your truck your putting it in and i'd fire the ports out the same side or out a side if you have a least some space for the sound to escape.

fronts probably best though then you can try with the box firing to you or to the trunk lid. if you dynomat the trunk you likely will get a boost in SPL from rear firing the woofers/ports into dynomat

Frito11
05-31-2011, 12:42 AM
here this will better explain how each panel comes together

http://i395.photobucket.com/albums/pp33/Frito_023/memph10.jpg

edit.

it would be a good idea to add a couple vertical braces betweent the top and bottom panels to stiffen them up. the other dims are small enough that they don't really need bracing imo.