DF

"David F. Eisan"

02/08/2003 7:57 PM

I need math help!

Dear All,

I am sure some of you can solve this in your head, but I don't know how to
do this.

I have a box that I need to solve the interior volume for.

The side of the box has four sides. The base is 10-7/8", the one side that
is at a 90 degree angle to the base in 4" high, the other two lengths are
10" and 10-1/2". The box is 8-7/8" wide and the material is 3/4" MDF.

What is my interior volume?

This box is for a subwoofer and I know the range that the box can fall
within, 1/3 cubic foot to 3/4 cubic foot. I was aiming for the high side,
and I hope I am close.

Thanks for your help,

David.

Every neighbourhood has one, in mine, I'm him.

Remove the "splinter" from my email address to email me.

Newbies, please read this newsgroups FAQ.

rec.ww FAQ http://www.robson.org/woodfaq/
Archives http://groups.google.com/advanced_group_search
Crowbar FAQ http://www.klownhammer.org/crowbar


This topic has 21 replies

DB

Dave Balderstone

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 8:09 PM

I can't picture the box you're describing. Can you have mercy on this
poor stubble-jumper and start again?

Your base is 10-7/8. Square?

Then how do the other dimensions come into play?

djb

--
"I'll do the stupid thing first and then you shy people follow..." - Frank Zappa

DB

Dave Balderstone

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 2:50 AM

In article
<[email protected]>, David F.
Eisan <[email protected]> wrote:

> Here is a link to a pic of the box,

That helps a lot.

Measure the inside of the bottom part where you can picture a regular
box.

Volume 1.

pretend the angled part at the top iis another box on top of that, then
divide volume by 2 to get volume 2

Add the two numbers.

You'll be close.

djb

--
"If you wind up with a boring, miserable life because you listened to your mom,
your dad, your teacher, your priest or some guy on TV telling you how to do
your shit, then YOU DESERVE IT." -- From the Real Frank Zappa book

Cc

"CW"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 4:53 PM

I havn't seen a car audio amp yet that would really put out what they say
but assuming that yours does, I hope you have a large aftermarket alternator
or you won't be able to listen to it and use your headlights at the same
time.
"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> Dear Leon,
>
> > How are you going to put a 15" speaker into such a small box?
>
> Umm, it will not be a 15" sub, I do not have the space.
>
> This is for my 2003 Ford Ranger extended cab pickup. I didn't want to use
up
> the entire back of the cab, I wanted to extend the centre console and put
a
> sub in there that wouldn't interfere with the jump seats or front seat
> movement, reclining.
>
> The sub I am using is a Kicker Solo Baric 8" sub, it is square, so in
effect
> it sounds and acts larger than it's 8" size would suggest. The sub will be
> driven by a 350 watt RMS Alpine mono amp. This was the best set-up I could
> come up with, given my limited space
>
> I have to finish it this weekend, the sub, speakers and amps are being
> installed on Tuesday. I will post pics if you really wanna know.
>
> Thanks,
>
> David.
>
> Every neighbourhood has one, in mine, I'm him.
>
> Remove the "splinter" from my email address to email me.
>
> Newbies, please read this newsgroups FAQ.
>
> rec.ww FAQ http://www.robson.org/woodfaq/
> Archives http://groups.google.com/advanced_group_search
> Crowbar FAQ http://www.klownhammer.org/crowbar
>
>

Lr

"Leon"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 10:37 PM

I can hear the subs in the kids cars pounding a half block away from my
closed up house.


"CW" <[email protected]> wrote in message
news:36bXa.55873$o%2.27523@sccrnsc02...
> I havn't seen a car audio amp yet that would really put out what they say
> but assuming that yours does, I hope you have a large aftermarket
alternator
> or you won't be able to listen to it and use your headlights at the same
> time.

Lr

"Leon"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 3:44 PM

Ohhhh.. ;~) So are you gonna be one those people that ride around with the
sub turned up so much that all the sheet metal and door trim panels rattle?


JD

John DeBoo

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 11:09 AM

David F. Eisan wrote:

> Dear All,
>
> I am sure some of you can solve this in your head, but I don't know how to
> do this.
>
On a serious note, try locating a large paperback named "Mathematics
Made Easy". Cost is around $8 or so. It covers all manner of math
problems, questions and formulas that assist with everyday stuff.
Answers are all in the back. Good book.

Lr

"Leon"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 3:31 PM

LOL.... 6" That ain't a Sub Woofer... That's more of a mid range
speaker...;~)




"CW" <[email protected]> wrote in message
news:ajYWa.51336$uu5.5275@sccrnsc04...
> He's not. It's likely a 6 inch.
> "Leon" <[email protected]> wrote in message
> news:[email protected]...
> > How are you going to put a 15" speaker into such a small box?
>
>

Cc

"CW"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 10:39 PM

373.2527 cubic inches inside volume.
"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> > Here is a link to a pic of the box,
> >
> > http://members.rogers.com/dfeisan/images/subbox1.jpg
>
> In the picture, you can see the base of the side facing the camera, (the
> face bottom edge on my bench), that edge is 10-7/8". The only right angle
on
> the side of the box is on the left, coming up from the base, that left
edge
> in 4". The edge that the speaker in sitting on is 10-1/2". The right edge
> coming up from the base, the one with my speed square beside it is 10".
>
> The depth, or width of the box, along the dimension where the clamps are
is
> 8-7/8".
>
> I am sure there are math terms for these measurements defining sides of an
> irregular polygon [I think that is what I am making :).], but I don't
think
> I ever knew them...
>
> Is this enough info to understand the shape of the box?
>
> Thanks,
>
> David.
>
> Every neighbourhood has one, in mine, I'm him.
>
> Remove the "splinter" from my email address to email me.
>
> Newbies, please read this newsgroups FAQ.
>
> rec.ww FAQ http://www.robson.org/woodfaq/
> Archives http://groups.google.com/advanced_group_search
> Crowbar FAQ http://www.klownhammer.org/crowbar
>
>

Cc

"CW"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

04/08/2003 1:01 AM

Sure can but they are not putting out near as much power as they (or the
manufacturer) claim. I spent a fair amount of time going over the numbers
some time back from several different manufacturers. Their claimed output
power just could not have been true. In a lot of cases, the claimed output
power exceeded the input.
"Leon" <[email protected]> wrote in message
news:[email protected]...
> I can hear the subs in the kids cars pounding a half block away from my
> closed up house.
>
>
> "CW" <[email protected]> wrote in message
> news:36bXa.55873$o%2.27523@sccrnsc02...
> > I havn't seen a car audio amp yet that would really put out what they
say
> > but assuming that yours does, I hope you have a large aftermarket
> alternator
> > or you won't be able to listen to it and use your headlights at the same
> > time.
>
>

DF

"David F. Eisan"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 3:08 PM

Dear Leon,

> How are you going to put a 15" speaker into such a small box?

Umm, it will not be a 15" sub, I do not have the space.

This is for my 2003 Ford Ranger extended cab pickup. I didn't want to use up
the entire back of the cab, I wanted to extend the centre console and put a
sub in there that wouldn't interfere with the jump seats or front seat
movement, reclining.

The sub I am using is a Kicker Solo Baric 8" sub, it is square, so in effect
it sounds and acts larger than it's 8" size would suggest. The sub will be
driven by a 350 watt RMS Alpine mono amp. This was the best set-up I could
come up with, given my limited space

I have to finish it this weekend, the sub, speakers and amps are being
installed on Tuesday. I will post pics if you really wanna know.

Thanks,

David.

Every neighbourhood has one, in mine, I'm him.

Remove the "splinter" from my email address to email me.

Newbies, please read this newsgroups FAQ.

rec.ww FAQ http://www.robson.org/woodfaq/
Archives http://groups.google.com/advanced_group_search
Crowbar FAQ http://www.klownhammer.org/crowbar

DF

"David F. Eisan"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 8:24 PM

> Here is a link to a pic of the box,
>
> http://members.rogers.com/dfeisan/images/subbox1.jpg

In the picture, you can see the base of the side facing the camera, (the
face bottom edge on my bench), that edge is 10-7/8". The only right angle on
the side of the box is on the left, coming up from the base, that left edge
in 4". The edge that the speaker in sitting on is 10-1/2". The right edge
coming up from the base, the one with my speed square beside it is 10".

The depth, or width of the box, along the dimension where the clamps are is
8-7/8".

I am sure there are math terms for these measurements defining sides of an
irregular polygon [I think that is what I am making :).], but I don't think
I ever knew them...

Is this enough info to understand the shape of the box?

Thanks,

David.

Every neighbourhood has one, in mine, I'm him.

Remove the "splinter" from my email address to email me.

Newbies, please read this newsgroups FAQ.

rec.ww FAQ http://www.robson.org/woodfaq/
Archives http://groups.google.com/advanced_group_search
Crowbar FAQ http://www.klownhammer.org/crowbar

Cc

"CW"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

03/08/2003 12:03 AM

He's not. It's likely a 6 inch.
"Leon" <[email protected]> wrote in message
news:[email protected]...
> How are you going to put a 15" speaker into such a small box?

DF

"David F. Eisan"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 8:05 PM

Here is a link to a pic of the box,

http://members.rogers.com/dfeisan/images/subbox1.jpg

Thanks,

David.

Every neighbourhood has one, in mine, I'm him.

Remove the "splinter" from my email address to email me.

Newbies, please read this newsgroups FAQ.

rec.ww FAQ http://www.robson.org/woodfaq/
Archives http://groups.google.com/advanced_group_search
Crowbar FAQ http://www.klownhammer.org/crowbar

Hh

"Herbster"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 1:02 PM

Volume = Length x Width x Height

Length multiplied by Width gives you the area of the bottom of the box in
square units - as in square inches.

Multiply that number by the Height to find the Volume in cubic units - as in
cubic inches.

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http://www.coupon-codes.neonmovie.com/amazon-coupon-1199
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> Dear All,
>
> I am sure some of you can solve this in your head, but I don't know how to
> do this.
>
> I have a box that I need to solve the interior volume for.
>
> The side of the box has four sides. The base is 10-7/8", the one side that
> is at a 90 degree angle to the base in 4" high, the other two lengths are
> 10" and 10-1/2". The box is 8-7/8" wide and the material is 3/4" MDF.
>
> What is my interior volume?
>
> This box is for a subwoofer and I know the range that the box can fall
> within, 1/3 cubic foot to 3/4 cubic foot. I was aiming for the high side,
> and I hope I am close.
>
> Thanks for your help,
>
> David.
>
> Every neighbourhood has one, in mine, I'm him.
>
> Remove the "splinter" from my email address to email me.
>
> Newbies, please read this newsgroups FAQ.
>
> rec.ww FAQ http://www.robson.org/woodfaq/
> Archives http://groups.google.com/advanced_group_search
> Crowbar FAQ http://www.klownhammer.org/crowbar
>
>

Hh

"Herbster"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 1:16 PM

Ah. OK. Sorry. The picture helps a lot.

Visually, divide your speaker housing into TWO boxes.

The rectangular one on the bottom - compute volume as already described.

The triangular box - for lack of a better term - on the top - compute the
area using the same formula - then divide the result by 2.

Add the two volumes together to get the total volume.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Amazon Coupons, Sweepstakes and Bargains
http://www.coupon-codes.neonmovie.com
Over 1200 Amazon Coupon Codes, Rebates and Special Offers
$20 Promotional Certificate with Amazon.com Platinum Visa Card
http://www.coupon-codes.neonmovie.com/amazon-coupon-1199
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> Hello there,
>
> > Volume = Length x Width x Height
> >
> > Length multiplied by Width gives you the area of the bottom of the box
in
> > square units - as in square inches.
> >
> > Multiply that number by the Height to find the Volume in cubic units -
as
> in
> > cubic inches.
>
> That works when all angles are right angles, the side of this box only has
> one 90 degree angle, I don't know what the other three angles are.
>
> Thanks,
>
> David.
>
> Every neighbourhood has one, in mine, I'm him.
>
> Remove the "splinter" from my email address to email me.
>
> Newbies, please read this newsgroups FAQ.
>
> rec.ww FAQ http://www.robson.org/woodfaq/
> Archives http://groups.google.com/advanced_group_search
> Crowbar FAQ http://www.klownhammer.org/crowbar
>
>

WE

"William E. Prisavage"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 5:33 PM

.255 cu ft.Check the forum post as to how I got the answer.
I think I got it close enough
"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> Dear All,
>
> I am sure some of you can solve this in your head, but I don't know how to
> do this.
>
> I have a box that I need to solve the interior volume for.
>
> The side of the box has four sides. The base is 10-7/8", the one side that
> is at a 90 degree angle to the base in 4" high, the other two lengths are
> 10" and 10-1/2". The box is 8-7/8" wide and the material is 3/4" MDF.
>
> What is my interior volume?
>
> This box is for a subwoofer and I know the range that the box can fall
> within, 1/3 cubic foot to 3/4 cubic foot. I was aiming for the high side,
> and I hope I am close.
>
> Thanks for your help,
>
> David.
>
> Every neighbourhood has one, in mine, I'm him.
>
> Remove the "splinter" from my email address to email me.
>
> Newbies, please read this newsgroups FAQ.
>
> rec.ww FAQ http://www.robson.org/woodfaq/
> Archives http://groups.google.com/advanced_group_search
> Crowbar FAQ http://www.klownhammer.org/crowbar
>
>

EP

"Edwin Pawlowski"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 10:28 PM



"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> Here is a link to a pic of the box,
>
> http://members.rogers.com/dfeisan/images/subbox1.jpg
>
> Thanks,
>
> David.

Been a long time since I used some of the math needed. Section it and it
will be much easier to do each portion.

If all else fails, fill it with sawdust. Then measure how much sawdust by
pouring it into a known measure.
Ed
[email protected]
http://pages.cthome.net/edhome


LL

"Lawrence L'Hote"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 8:23 PM


"David F. Eisan" <[email protected]> wrote in message
news:[email protected]...
> Here is a link to a pic of the box,
>
> http://members.rogers.com/dfeisan/images/subbox1.jpg


Volume of bottom, rectangular solid part is length x width x height = volume
1
volume of prism-shaped top = length x width x height/2 = volume 2
total volume = volume 1 + volume 2

1 cubic foot = 12x12x12 cubic inches

Larry

Jl

"Jonathan"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 5:12 PM

> The side of the box has four sides. The base is 10-7/8", the one side that
> is at a 90 degree angle to the base in 4" high, the other two lengths are
> 10" and 10-1/2". The box is 8-7/8" wide and the material is 3/4" MDF.
>
> What is my interior volume?
>
> This box is for a subwoofer and I know the range that the box can fall
> within, 1/3 cubic foot to 3/4 cubic foot. I was aiming for the high side,
> and I hope I am close.
>

Your dimensions are for the outside of the box, yes? And you need the
interior airspace volume, not including the MDF walls, right?

I get .199 cubic feet... 343.27 cubic inches... Drew it in Autocad to get
the area of the side...

If the dimensions you gave were for the inside of the box and not the
outside... .363 ft cubed, or 627.4 inches cubed...

Jonathan

c

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

02/08/2003 6:45 PM

"Edwin Pawlowski" <[email protected]> wrote:

>Been a long time since I used some of the math needed. Section it and it
>will be much easier to do each portion.
>
>If all else fails, fill it with sawdust. Then measure how much sawdust by
>pouring it into a known measure.
>Ed

Damn, a fully on topic post using sawdust. U da man!!!!!

Wes
--
Reply to:
Whiskey Echo Sierra Sierra AT Gee Tee EYE EYE dot COM
Lycos address is a spam trap.

Lr

"Leon"

in reply to "David F. Eisan" on 02/08/2003 7:57 PM

04/08/2003 12:39 PM

I see what you are saying now.... I have been very leery of any equipment
and or amp that does not rate its power in RMS watts. IMHO unless the
stated power is not RMS rated it closely resembles those 6 HP 110 motors..
;~)



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