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trapezium sub enclosure calculator?



 
 
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  #1  
Old March 30th 05, 03:28 PM
AntiSpammer
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Default trapezium sub enclosure calculator?

anyone knows if there is a good tutorial + software calculator on designing
a trapezium box?
math is killing me...
I have tried searching everywhere.....


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  #2  
Old March 30th 05, 09:23 PM
Scott Gardner
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On Wed, 30 Mar 2005 22:28:07 +0800, "AntiSpammer" >
wrote:

>anyone knows if there is a good tutorial + software calculator on designing
>a trapezium box?
>math is killing me...
>I have tried searching everywhere.....
>

What exactly do you mean by "trapezium"? Americans usually use this
to describe a four-sided figure with no parallel sides. To the
British, it's a four-sided figure with two parallel sides (what we in
America usually call a "trapezoid".

If you have two parallel sides, the area is 0.5 X (a+b) X h, where a
and b are the lengths of the two parallel sides, and h is the height.
After you find that, multiply by the depth of the box to get the
volume.

If you have no parallel sides at all, the math gets trickier.
Describe exactly how your enclosure is shaped, and I can probably work
out a formula for the volume.


--
Scott Gardner

"You don't need to fire the rig foreman that just blew the top off the wellhead, cause you know for damned sure he'll never do it again." (Ron Gardner)

  #3  
Old March 31st 05, 02:36 AM
spam
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Posts: n/a
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Scott Gardner wrote:
> On Wed, 30 Mar 2005 22:28:07 +0800, "AntiSpammer" >
> wrote:
>
>
>>anyone knows if there is a good tutorial + software calculator on designing
>>a trapezium box?
>>math is killing me...
>>I have tried searching everywhere.....
>>

>
> What exactly do you mean by "trapezium"? Americans usually use this
> to describe a four-sided figure with no parallel sides. To the
> British, it's a four-sided figure with two parallel sides (what we in
> America usually call a "trapezoid".
>
> If you have two parallel sides, the area is 0.5 X (a+b) X h, where a
> and b are the lengths of the two parallel sides, and h is the height.
> After you find that, multiply by the depth of the box to get the
> volume.
>
> If you have no parallel sides at all, the math gets trickier.
> Describe exactly how your enclosure is shaped, and I can probably work
> out a formula for the volume.
>
>



I've done that before. no 2 sides are parallel. It's a bitch to figure
out. especially when it has to be exact as when building ported
enclosures. What I did was break the box down into the various triangles
and figure the volume of each one.

  #4  
Old March 31st 05, 04:28 AM
Antispammer
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Posts: n/a
Default

yupz, a trapeziod. To be exact, it's actually a trapezoid on top of a
rectangle.
Due the 45-75 degree slope, I guess the subs can only be mounted by
increasing the height. They will be firing at the rear at such an angle so
that the sound will be reflex to the front of the vehicle.
It's a Dual 15" box with slot port that I wanted. I have no restrictions on
the box size.
any suggestions?

subs specs
Fs = 28 Hz
Qms = 4.68
Vas = 123.3 liters
Xmax = 32 mm
Xmax (parallel) = 32 mm
Xmax (series) = 32 mm
Sd = 125.6 sq.in
Qes = 1.1
Qes (parallel) = 0.55
Qes (series) = 0.55
Re = 1.9 ohms
Re (parallel) = 0.95 ohm
Re (series) = 3.8 ohms
Z = 2 ohms
Z (parallel) = 1 ohm
Z (series) = 4 ohms
BL = 1.922 lb/A
BL (parallel) = 1.922 lb/A
BL (series) = 3.844 lb/A
Pe = 800 watts
Pe (parallel) = 1600 watts
Pe (series) = 1600 watts
Qts = 0.89
Qts (parallel) = 0.49
Qts (series) = 0.49
1-W SPL = 85.8 dB
1-W SPL (parallel) = 88.7
1-W SPL (series) = 88.7




"Scott Gardner" > wrote in message
news
> On Wed, 30 Mar 2005 22:28:07 +0800, "AntiSpammer" >
> wrote:
>
> >anyone knows if there is a good tutorial + software calculator on

designing
> >a trapezium box?
> >math is killing me...
> >I have tried searching everywhere.....
> >

> What exactly do you mean by "trapezium"? Americans usually use this
> to describe a four-sided figure with no parallel sides. To the
> British, it's a four-sided figure with two parallel sides (what we in
> America usually call a "trapezoid".
>
> If you have two parallel sides, the area is 0.5 X (a+b) X h, where a
> and b are the lengths of the two parallel sides, and h is the height.
> After you find that, multiply by the depth of the box to get the
> volume.
>
> If you have no parallel sides at all, the math gets trickier.
> Describe exactly how your enclosure is shaped, and I can probably work
> out a formula for the volume.
>
>
> --
> Scott Gardner
>
> "You don't need to fire the rig foreman that just blew the top off the

wellhead, cause you know for damned sure he'll never do it again." (Ron
Gardner)
>



  #5  
Old March 31st 05, 07:09 AM
mark
external usenet poster
 
Posts: n/a
Default

It sounds like it should be a crazy box to build. What is it going
in(just curious)? What kind of subs are they?
I built a box for 2 kicker Comp's with a slotted port in a chevy S10
that was absolutely awesome. The guy is winning local competitions with
it frequently.

Antispammer wrote:
> yupz, a trapeziod. To be exact, it's actually a trapezoid on top of a
> rectangle.
> Due the 45-75 degree slope, I guess the subs can only be mounted by
> increasing the height. They will be firing at the rear at such an angle so
> that the sound will be reflex to the front of the vehicle.
> It's a Dual 15" box with slot port that I wanted. I have no restrictions on
> the box size.
> any suggestions?
>
> subs specs
> Fs = 28 Hz
> Qms = 4.68
> Vas = 123.3 liters
> Xmax = 32 mm
> Xmax (parallel) = 32 mm
> Xmax (series) = 32 mm
> Sd = 125.6 sq.in
> Qes = 1.1
> Qes (parallel) = 0.55
> Qes (series) = 0.55
> Re = 1.9 ohms
> Re (parallel) = 0.95 ohm
> Re (series) = 3.8 ohms
> Z = 2 ohms
> Z (parallel) = 1 ohm
> Z (series) = 4 ohms
> BL = 1.922 lb/A
> BL (parallel) = 1.922 lb/A
> BL (series) = 3.844 lb/A
> Pe = 800 watts
> Pe (parallel) = 1600 watts
> Pe (series) = 1600 watts
> Qts = 0.89
> Qts (parallel) = 0.49
> Qts (series) = 0.49
> 1-W SPL = 85.8 dB
> 1-W SPL (parallel) = 88.7
> 1-W SPL (series) = 88.7
>
>
>
>
> "Scott Gardner" > wrote in message
> news >
>>On Wed, 30 Mar 2005 22:28:07 +0800, "AntiSpammer" >
>>wrote:
>>
>>
>>>anyone knows if there is a good tutorial + software calculator on

>
> designing
>
>>>a trapezium box?
>>>math is killing me...
>>>I have tried searching everywhere.....
>>>

>>
>>What exactly do you mean by "trapezium"? Americans usually use this
>>to describe a four-sided figure with no parallel sides. To the
>>British, it's a four-sided figure with two parallel sides (what we in
>>America usually call a "trapezoid".
>>
>>If you have two parallel sides, the area is 0.5 X (a+b) X h, where a
>>and b are the lengths of the two parallel sides, and h is the height.
>>After you find that, multiply by the depth of the box to get the
>>volume.
>>
>>If you have no parallel sides at all, the math gets trickier.
>>Describe exactly how your enclosure is shaped, and I can probably work
>>out a formula for the volume.
>>
>>
>>--
>>Scott Gardner
>>
>>"You don't need to fire the rig foreman that just blew the top off the

>
> wellhead, cause you know for damned sure he'll never do it again." (Ron
> Gardner)
>
>
>


  #6  
Old August 17th 12, 08:00 AM posted to rec.audio.car
[email protected]
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Posts: 2
Default trapezium sub enclosure calculator?

Here you have solution for maths. http://www.easycalculation.com/area/learn-trapezium.php
Check it for tutorials and software calculator.

 




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