View Full Version : Problem when calculating Sealed Box design..

06-28-2011, 12:38 PM
So I bought a new car and I no longer have room for ported, which is fine. I decided to calculate out the best sealed box for my sub and so i went here:

Car Audio - Sealed Subwoofer Box Design Calculator (http://www.carstereo.com/help/Articles.cfm?id=26)

and used these specs:

FS: 26.7Hz
Qms: 3.67
Vas: 69L
Cms: .22mm/N
Mms: 161g
Rms: 7.32
Xmax: 23mm
Xmech: 32mm
Sd: 471sqcm
Vd p-p: 2.16L
Qes: .36
Re: 3.2ohm
Le: .196mH
Z: 4ohm
Bl: 15.6Tm
Pe: 1000W
Qts: .32
1WSPL: 87.7db
2.83V: 91.7dB

I also used

AJ Sealed Designer to make sure the response was right.

Now here is the problem.. If i use a normal Qtc of ~ 0.8 - 1.2 my box IS HUGE, anything above 1.2 Qtc and now im peaking at like 1khz.. wtf

The flattest response requires a 67cu ft box! even at 1.2 Qtc i need 5.282 CUFT SEALED!!!

I was looking to make ~ 1.5 cuft sealed for the sub but now it seems that that design is WAY too small for this sub.

Someone please help me.



Here is the same result with WINISD:
http://img221.imageshack.us/img221/3852/unledygk.png (http://imageshack.us/photo/my-images/221/unledygk.png/)

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