What's new

enclosure help (1 Viewer)

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
I am attempting to build my first enclosure for a 10" sub. I have dowloaded and tried some sealed and ported enclosure spreadsheets. I was wondering what is better, sealed or ported. I have read many who say sealed. Also when I do the calculations I get a result of .50 cubic feet for size. That does not sound right to me. That would be aprox. a 12" x 12" x 6 enclosure. 6 inches does not sound like a proper depth considering the depth of the sub is 4 3/16" . Can anybody give me any help or input?

Thanks in advanced
 

Dan Hine

Screenwriter
Joined
Oct 3, 2000
Messages
1,312
:frowning: I can't find any T/S parameters for an MTX home sub driver. Lots of Car woofers though. You wouldn't happen to have the T/S specs would you?
 

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
they are for the mtx 6000 series. They are probably for car use, but was hoping to experiment with them as home use. I have all the specs if you need them.

thanks
 

Dan Hine

Screenwriter
Joined
Oct 3, 2000
Messages
1,312
Definitely more suited for car audio. The size enclosure it would have to go in for flat response down to even 20hz puts the driver in position to bottom with only 75-100watts of power. And at that level the output just isn't very high (would benefit highly from 20db of cabin gain...again pointing to the fact that it is a car audio driver). I doesn't look like a bad driver if you want to put it in your car, but I'd really look for something else for your home.

But that is just me. ;)
 

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
thanks for your advice, but I would really like to experiment with this driver for home use. Just an experiment of mine, but I am just thrown off by the dimensions i got from the spreadsheet.
 

Brian Bunge

Senior HTF Member
Joined
Sep 11, 2000
Messages
3,716
What about the dimensions is throwing you off? A 12" x 12" x 6" enclosure is .5ft^3. You don't have to use those exact dimensions though.
 

Dan Hine

Screenwriter
Joined
Oct 3, 2000
Messages
1,312
Mike,

I must be using different numbers than you. Could you post the specs for the sub you have? I'm not getting anything near that small a box size to look halfway decent. Also, what program are you using? Unibox, WinISD, other?
 

Frank Carter

Screenwriter
Joined
Mar 12, 2002
Messages
1,187
Here's some T/S parameters on MTX T61044a. Mike said it was an 8 ohm sub and this is dual 4 ohm, it's the only one that can be wired to 8 ohms so I gues this might be it.

Fs: 30.9hz
Vas: 40.1L
Qts: .60
Qes: .69
Qms: 4.63
Re: 1.58ohms
Sd: 367cm^2
Xmax: 9.4mm
 

Dan Hine

Screenwriter
Joined
Oct 3, 2000
Messages
1,312
Frank,

Yeah, that's the one I used. Sealed, I like how it looks between 3.5 and 4 cubic feet. Vented seems to favor around 5cubic feet tuned to around 21hz. At least, that's what I like. :) All this leaves me very confused as to how Mike was getting .5cubic ft. as a suggested box size. :confused:

Of course, either way, give it more than 100 watts and you're in trouble down low. Mike, I'd hate to see you damage your drivers...be careful!
 

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
here are the specs and my mistake, I was using the 8" 4 ohm specs, but even now with these specs I get 20.41 cubic feet. That still sounds wrong.

Thanks for everyones help.

Vas34.510
Qts0.680
Qes0.760
fs33.3
Xmax9.40
Qms 6.76
Re 6.29ohms
xmax 9.4mm
 

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
okay so I just used winISD to input some driver information and got some results that maybe I need some help with.

I received a 33.5 l volume for the design.

the dimenisions are as follows:

w - 0.363 m = 14.37 "
h - 0.559 m - 22.09 "
d - 0.232 m - 9.21 "

can i minipulate these numbers as long as they equal the same total ( take 4 inches from the h and add it to the d? )

22 seems a little high to me, maybe I am wrong and it is exactly right.

also 33.5 l = 1.2 cubic feet. 1.2 cubic feet give aprox 14" by 14" by 10.7 ". How is that so off of the other dimensions?

hope all this makes sense and forgive me if it does not.

Thanks

Mike
 

Patrick Sun

Senior HTF Member
Joined
Jun 30, 1999
Messages
39,612
You have to arrive at the same internal volume with the changes in the dimensions (W x H x D). You can't simply add length in one dimension, and subtract it from another. Use your algebraic/geometry skills.

The internal volume is a fixed value. Pick the 2 other dimensions to your desired lengths, and the 3rd dimension much be the (internal volume)/(dimension 1 x dimension 2).

(Note - I've merged both threads on the same topic into one thread).
 

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
Maybe this would be an easier way if anyone is willing to help.

I will post my specs for the speakers and any experienced cabinet makers maybe can give me what their dimensons would be based on these. I am getting confused by different results I am getting and I have never attempted this before so any input would be greatly appreciated.

Vas130.000
Qts0.320
Qes0.450
fs26.0
Xmax7.62
Dia.30.48
PEMax250

Constants
Ro1.18
c345.00



Enclosure Specifications
Desired Qtc0.60
Qr1.88
Vr2.52
Vb51.68
Fb48.8
F358.9

Sd7.30E-02
Vd5.56E-04
n00.005
SPL88.9
K10.741
K2110.696
Amax1.000
Par0.741
Per151
PeakSPL113

thanks for your time and help

Mike
 

MikeHeath

Grip
Joined
Jan 21, 2003
Messages
23
so i have spent all afternoon researching, playing with numbers, etc. and have come to a reasonable ( I think) calculation.

1.82 cubic feet which equals 3144.96 cubic inches

a 12 " x 15" x 18.75 " (golden ratio included) enclosure equals 3375 cubic inches.

I read up to a 20% difference would not make a noticable difference.

do these dimensions make senses according to the above t/s parameters?

thanks for info!
 

Brian Bunge

Senior HTF Member
Joined
Sep 11, 2000
Messages
3,716
Mike,

It's not necessary to use a golden ratio enclosure for subwoofers. If the 1.82ft^3 enclosure gives you the Qtc you are looking for then that is the box you should use.
 

Users who are viewing this thread

Forum Sponsors

Latest Articles

Forum statistics

Threads
355,229
Messages
5,074,199
Members
143,845
Latest member
aotorusxwxr
Recent bookmarks
0
Top