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Torres' Box Tuning Calculator - Updated 8/18


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#1
Torres

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UPDATED!!! finally got everything worked out that i wanted, plus a neat addition or two.

***When downloading, make sure it is saved with a .exe file extension, or it will not open properly. the 'Open with...' window will pop up otherwise*** (thanks gottahavbass917 and a user from another forum :))

To do this, go to the folder that the calculator is in and click tools in the toolbar at the top (click alt on the keyboard if you can't see the toolbar). Then click folder options. then click the view tab, and in the advanced settings window, there's a check box that says 'hide extensions for known file types'. Uncheck that and you will see the .uexe file extension on the calculator. Take out that U and save it (just as .exe) and it should work. Now you can go back and recheck the check box and hide known file types.

Also, should have said this from the get-go (I apologize) but thanks to Razor5070 for the help when i got stuck :)

Here's the new look:

Posted Image

In a week or so, as long as I can make completely sure all kinks are worked out, I'm going to redo the layout and upload that as another download. The original one will stay up as well, but it'll be easier to fix anything and then redo the layout and upload rather than adjusting everything to fix and then readjusting everything. It'll be more for widescreen users and everything should be accessible from the get-go.

Changelog:

-Metric in millimeters and centimeters
-Changeable backgrounds and fonts. View the help window for more info.
-Individual inputs for bracing and subwoofer displacement
-User input for port thickness
-Added port ratio box
-Port area range removed
-Screen Shot button added. Will open MS paint and can save from there.


Here's the download link to the program:
Click to download Torres' Box Tuning Calculator

***you'll need the most up to date .net framwork for this program to work. click this link to get it***
.NET Framework

If you're .NET is up to date, and you're still having troubles opening the calculator, check to make sure it downloaded as a .exe file. It should have normally, but for some it may not. Rename it with a .exe format and it should work. Thanks to pervitizm for finding this solution.

For Mac users:
This is a windows based program, so it will not work on macs from a fresh download. You'll need to use either parallels, virtualbox, VMWare fusion, or wine.


There's port cut sheets in there, but one thing i did NOT include are cut sheets on how to cut the port if it bends. There's too many different ways to cut the sheets, and the coding to go into that would be too tedious to deal with. Maybe at another time down the road. Right now I want to get it uploaded and not have something silly holding it back. Plus, if you're building a speaker box, I'm sure you can go take some measurements in the box and see what the port should be :)

READ THE FAQ/HELP!!!!
I've answered questions repetitively because the help window was not read. So read that first please.

I've also included a FAQ/tip sheet with it this time around. So if you get confused with something, click there first. If you're STILL confused, send me a PM with any questions. With that being said, I'm still going to paste all the contents of the FAQ here.

Box Frequency Tuning Calculator - FAQ/Tip Guide
*------------------------------------------------------------------------------------------------*

1 - First and foremost, the RE calculator is *not* spot on, and is limited in design, so no, it will not match this calculator.

2 - When doing an oddly shaped box such as a fiberglass box, or you know the volume of a certain box you have in mind
that you want to build, put the net volume in the 'Desired Net Volume' box. This will bypass all dimensions entered
preventing you from having to guess dimensions to get a certain net volume and will allow you to tinker with different
port sizes and tuning. So if you know you want a box with 4 cubic feet of net volume, enter '4' into that box and it
will allow you to adjust tuning accordingly to that specific volume. Keep in mind that any displacement nor port volume
is NOT subtracted from this total. Any number in this box will override any number in the 'Desired Gross Volume' box.

3 - The 'Desired Gross Volume' box acts much like the 'Desired Net Volume' box, except all displacements are taken into
effect.

4 - If the '# of ports' box is greater than 0, that will automatically get taken into effect and the calculator will ignore the
dimensions for slot ports.

5 - The '# of Common Port Walls' box refers to how many sides of the box are going to act as sides of the port. This is
done by looking at the port head on and counting how many sides of the box that face of the port uses as the port
walls. The port inside the box has nothing to do with the common port walls. Please refer to the links below for
examples.

6 - Aero ports have a defaulted thickness of 3/16" -- couldn't decide whether to use 1/8" or 1/4" so I went in the middle.

7 - Port length uses the box wall or baffle(s) as part of the port length. So a port that is 10" long with one baffle using .75"
wood will only need to be 9.25" long since the box wall or baffle(s) will account for the other .75". If using two baffles,
then it would be 8.5" long as the baffle will account for 1.5" of port length and so on.

8 - When using multiple ports, whether they be round or rectangular ports, the port length MUST be the same for each
port. The port length does **NOT** get divided among the ports. This will affect your net volume and severely
raise your tuning.

9 - Program resolution is set to 840 pixels in width and 780 pixels in height. Try to stay within this resolution for custom
backgrounds or program may lag. Using .png files will also help prevent program lag.

10 - The extra baffle box should only have a value if you plan on using multiple baffles. Leave blank or a zero if you are
only going to use a single baffle.

11 - Regular square/rectangle boxes do not need any numbers entered into the 'Height 2' or 'Depth 2' boxes.

12 - Pressing 'Enter' will prompt the program to print.

13 - PLEASE NOTE: 'Physical port length' refers to the length of the wood itself needed to build the port. This is NOT the
same as the effective port, or the port you entered into the port length box that the box will 'see'. You measure
on the inside of the port (against the port wall) to measure the physical port, in the same way you measure down
the middle of the port to get your actual, or effective, port length.

14 - When doing an external port, the full length of the port must be entered into the port length box. Then the length of
the external port in the 'External Port' box. This way the proper port length (the Port Length box) will be used for
the equation, and the proper volume will be added to the net volume (the volume of the external section of the port)
for proper tuning.

15 - On the cut sheets of boxes with different depths and heights, you'll notice 'H1' or 'D2' next to the measurements.
These represent which dimension is which. Here are two pictures to illustrate:

Box with one height, but two different depths:
Posted Image

Box with two heights and two different depths:
Posted Image

--The following are links that illustrate how each ported box is taken into effect in the calculator (sub and port position can be upwards with the same effect):

1 - Port with 0 common walls:
Posted Image

2 - Slot port with 1 common wall:
Posted Image

3 - Slot port with 2 common walls:
Posted Image

4 - Slot port with 3 common walls:
Posted Image

--The images were made with Google Sketchup. Free to download: http://sketchup.google.com/




Should be 99% debugged (I think). But after staring at the same coding for so long, things are bound to slip by. So IF you do find something that seems out of place, PM me about it please. Only if you're certain about it. I dont want to go check something or explain how it's done several times over because it may be coded a certain way that you may be thinking differently. That'd be too tedious for me to do constantly.

Hope you guys like it the update :)

And if you appreciate my work, buy me a beer :D
https://www.paypal.c...d=KSKSZ2SBUV6RS

Edited by Torres, 30 November 2012 - 02:08 AM.

My GUI Box Tuning Calculator Download - Updated 8/18/2012
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#2
Torres

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updated. i added 4 buttons to choose wood thickness. .75", 1", 1.5", and 2". figured that'd be the most extent of this at least. also added a box to display surface area of the port. link is in first post :)
My GUI Box Tuning Calculator Download - Updated 8/18/2012
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#3
Torres

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thanks!! sub displacement is usually .4. at least that's what it s on the spreadsheet calc i used

Edited by ExpoSport, 23 February 2009 - 08:00 AM.

My GUI Box Tuning Calculator Download - Updated 8/18/2012
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#4
Torres

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updated again. added a box to show the range of surface area of port you should have in conjunction to box volume. based on 12-16" per cubic foot to help get an idea of how much area to use without having to calculate it manually. nothing major...just something to look at if you need it :)

Edited by ExpoSport, 12 May 2009 - 09:07 PM.

My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#5
ae92boy

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hey exposport, your box calc works great for me, ...In calculating for the end port correction, I just add half of the port width to the actual length of the port....for example my port width is 3" and the length of the port is 16", what I do is to get half of 3", which is 1.5" and add that to the length of the port which is 16", to get the total port length with end port correction of 17.5"...will this formula work for your box calc? I'm quite confused on your post on the first page regarding your calculation for the end port.....hope you can enlighten me with this one....thanks....

#6
Torres

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when doing a slot port...just check the slot port box in the program and it will automatically figure in half of the port height for you into the tuning :) make sure to use *port height* as the distance from the port wall to the box wall. otherwise it will use a much longer number for end correction. so your port *height* would need to be 3". then enter in the port width. then enter 16" for port length. check the 'slot port' check box and it'll automatically add 1.5" to the port length inside the calculations :)
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

~~the light bulb wasnt an invention with 1000 failures...it was an invention with 1000 steps~~

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#7
Torres

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it's there because he sub 'sees' that extra little bit of port. so while it's not physically there, the port still acts that much longer
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#8
rckstar

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Okayyy, How do I take it into account when building the box though? say for instance 8" port length gives me 35hz and the correction is -9.5"

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#9
Torres

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check the slot port check box and end correction will automatically be taken into account
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#10
Torres

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no prob :)
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

~~the light bulb wasnt an invention with 1000 failures...it was an invention with 1000 steps~~

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#11
audiogod9000

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Ay bro, i got a quick ''Q''


When i do it, it comes out with 17x40x24 = 7.77 (your calculator), but with math it comes out to 17x40x24-4.5(3x.75)=9.4 .

Why is that?
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#12
Torres

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the gross volume in my calculator takes out the wood thickness. that's why under box dimensions it says outer dimensions so when you put in the measurements, it takes out the proper wood displacement. so your 9.4 is that whole box in itself, while the 7.77 is actual usable airspace before any other displacement. so basically the walls of the box take up 1.63 cubes of space
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#13
audiogod9000

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the gross volume in my calculator takes out the wood thickness. that's why under box dimensions it says outer dimensions so when you put in the measurements, it takes out the proper wood displacement. so your 9.4 is that whole box in itself, while the 7.77 is actual usable airspace before any other displacement. so basically the walls of the box take up 1.63 cubes of space



Well i mean with the math i use it does just the Internal space. 17x40x24 - 4.5 (6x.75) = 9.4
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Sub = Fi SSD 15''
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REFS: Bought From-Twistedchild420 ,J_black10,SojiaRaggs9000,hotshot27,

REFS: Sold To- James , sanitarium , qu1cks1lver56, skittlesRgood

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#14
Torres

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yes...but my calculator automatically takes off the proper amount depending on the thickness of the wood before figuring volume. so you need to put in external dimensions. if you're using .75" wood, put in 18.5x41.5x25.5 and you'll get 9.44. the calculator takes off 1.5" off each measurement and will use 17x40x24 to find the volume
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#15
Torres

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ive got a Q for you, how come when you check off, slot port everything changes? when you have the demensions already in for the port shouldent it calculate it the same? also when you check the port bends, why does it change the tuning and everything else? (also with that, where it says actual port length, it goes to a funny number) ive always used your old on you made, and just built my box's that way, but now im wondering with your new one if maybe i was building them wrong and they were not tuned to what i thought they were?

when doing a slot port, you get what's called 'end correction' which adds half the height of the port to the length, which lowers the tuning and effects net volume slightly. which is why you see things change. when the port bends, it doesnt need to be physically as long which also has a slight effect. you might not have been doin em wrong, they just werent as accurate. the more options there are...the more accurate it is. the update that i'm almost done with (just gotta debug and check for accuracy) pretty much takes into account EVERYTHING i could think of myself and with suggestions from others. so...it might not match that one either, but should be as good as it gets.

What is the formula that your calculator is using to compute the port volume, my hand calculations do not give the same results

Posted Image

make sure they are executed in the proper order.
My GUI Box Tuning Calculator Download - Updated 8/18/2012
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Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#16
Decaf

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that formula does not involve port volume, its seems that your calculator is also including the top and bottom thickness in its calculations, in which the only wood thickness needed is the port wall if using a slot port and both walls and top piece if it is not

It is a common misconception that the tuning frequency (fb) is a function of port volume when in fact, it is actually a function of the port's cross-sectional area and its length as given by the formula:

Posted Image

Where Av is the cross-sectional area of the port (in square inches),
Lv is the length of the port (in inches) and
Vb is the enlcosure's net volume (in cubic inches).


copied from this
http://mobile.jlaudi...php?page_id=165

Edited by Decaf, 07 January 2010 - 01:31 PM.

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#17
Torres

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more ideas to improve your calculator expo!

Few things I was thinking.

1)A way to plot the box's bandwidth and freq response.
2)Adding more exterior demensions, so that you can easily calculate "wedge" shaped boxes.
3)Allowing the ability to use 2, 3, or 4 ports. since sometimes when your using a round port you need multiples.
4)A visual layout of the box just for some added looks.

Might all be a pain in the ass, but i was just thinking a little

DAMN YOU! just as i was getting it all wrapped up! (i think) lol.

well...for #1 and 4, there's no way for me to do anything visual like that, not as of yet. i'm taking another semester of visual basic, so we'll see where that takes me. they have a section for images and graphics and whatnot, but i'm not sure what i'll be learning in this next class.

for #2, already got it :) got another depth for boxes like this:
Posted Image
and another height textbox for boxes like this:
Posted Image
:) as of now that's been the hardest part of debugging. i had first part right i think (havent checked it manually), but then when i'd add in another height for the second type box, the volume would jump from say 17 cubic feet to like 30+ somethin feet. i'd be like :shok: rearranged the coding 100 times, but then went through the coding itself and think i got it :D

and as for #3, i may be able to do that. adding in a radius/diameter box and a multiple port box wont be hard to do and figure in port area. i'll look into that ;)
My GUI Box Tuning Calculator Download - Updated 8/18/2012
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Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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#18
EricR

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ok i have a question also.

here is a SS of each box, both identical boxes and port except on one the port is on the side, the other port on top. but they are identical ports so why is the tuning changing so much.



Posted Image
Posted Image

Edited by EricR, 26 January 2010 - 05:55 PM.

i was thinking leave the 12 sitting in the box in the hole and duck tape from the bottom of the sub to the bottom of the baffle so the sub doesnt free air. would that work?


#19
Torres

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Sorry I'm still a little confused on this. I'm using this calculator also and ckecked slot port and port bends. My box is 22'' deep, port is 22'' long but it says (physical port length 16.5''). So since my baffle is part of the port I would cut one piece 15.75'' long and the 2nd piece 4.75''? I think that is correct just want to be sure before I start cutting. BTW box is 37W 17H 22D, port is 5.5x15.5x22long tuned to 37.--hz.

i think when i did the coding for the port length, i didnt take into account the proper displacement of the wood. doing in sketchup, i'm getting a piece 15" long. seeing as how the port bends, measure down the port and you'll get 22". here's a pic of what i mean:

Posted Image
add the numbers outside of the box in green and you'll get your port length

ok i have a question also.

here is a SS of each box, both identical boxes and port except on one the port is on the side, the other port on top. but they are identical ports so why is the tuning changing so much.

you have the 30 and the 8 switched on the port. if doing a slot port, the distance from the port wall to the box wall needs to go under port height or else a much bigger number will get added in for end correction in the port. in your case, one is adding 4", and the other is adding 15". port placement shouldn't change the measurements.
My GUI Box Tuning Calculator Download - Updated 8/18/2012
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#20
Torres

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Thanks for responding to my inquiries. The math for wedge boxes isn't hard, I have built several myself. I am still a bit confused as to why the newer version did increase the net volume when the slot port option was checked. Is that the way it should be? I would really like to see the formulas you are using so if you wouldn't mind can you pm them to me. If not then I understand.

I figured out how to get bass box to roughly estimate my final net volume with my slot port but it is still off from what the new version reports as the final net volume. This is where I am really hung up on the most. Using outer dimensions to figure gross volume and then subtracting all displacements (port, sub, bracing, etc) would decrease the gross and yield the net. But even when using one wall of the enclosure as a wall of the port does it really add as much as .29 ft^3 over using a port that has four walls?

Do you plan on adding calculations for labryinth ports as well? Would be nice since I usually make my ports that way. The labryinth port issue is why I was saying the old version reported my final net volume correctly.

yeah the math isnt hard at all. it's easy to understand. getting it into the program to execute properly is the hard part. last time i tried, i was .26 cubes off on the calculator to the paper. i think i have 23+ variables just to find the volume of a box with 2 different depths. i dont mind PMing you the formula. i have the picture version posted here, and it's basically the same thing, just on one line with lots of parenthesis. it's more how i get the numbers for the variables in the formula. which are all through the program lol. but i'll PM them if you want.

one thing i didnt take into consideration when making the current calculator was port displacement. a port with 4 independent sides will have a different displacement than the same port with 1 independent side. small things like that make the difference, which i have added in the new one. i did not do a labryinth port however. there's so many ways to do ports, it's hard to figure in a way to do all of them. so if i do that, it will most likely wait till another update. also, straight ports are more ideal than a port with lots of bends, which is why i do displacement for ports like that.

I have a question about the port bending? If my port bends twice Should I subtract the port height from the physical length a second time? Only if the second bend uses a outside corner? My second bend DOES NOT Use a corner of the box but turns 180% into middle of the box. I think the 180% length of physical port length is the second port height I am refering to? I think I should NOT subtract any pysical port length for the second bend because I am NOT using an outside wall for the second bend? I think this is right just want to make sure. Also if I kerf one side of the port opening WHERE do I start measuring my pysical port length? I think it is where the port walls start being parallel or starts a constant width but want to make sure. I know to subtract the dispacement that the kerfed opening takes up. Thanks in advance.

correct. not needed for the second bend. and i've heard different things with the kerf ports. some say what you're saying, where they're parallel, and some say halfway from the parallel point to the complete open flare. i'm not 100% sure either way, but i bet the difference would be very small
My GUI Box Tuning Calculator Download - Updated 8/18/2012
GUI = Graphical User Interface

Screws hold down wire and screws on top of screws are to hold the screws below tighter.

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