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#1




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




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 foursided figure with no parallel sides. To the British, it's a foursided 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




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 foursided figure with no parallel sides. To the > British, it's a foursided 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




yupz, a trapeziod. To be exact, it's actually a trapezoid on top of a
rectangle. Due the 4575 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 1W SPL = 85.8 dB 1W SPL (parallel) = 88.7 1W 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 foursided figure with no parallel sides. To the > British, it's a foursided 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




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 4575 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 > 1W SPL = 85.8 dB > 1W SPL (parallel) = 88.7 > 1W 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 foursided figure with no parallel sides. To the >>British, it's a foursided 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




trapezium sub enclosure calculator?
Here you have solution for maths. http://www.easycalculation.com/area/learntrapezium.php
Check it for tutorials and software calculator. 
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