different results with different box calcualtor programs

[akuma4u]

i have always used torres for designing enclosures but.. i downloaded some box calculator apps on my phone,. one was ct sounds app and another was ultimate car audio app.. BOTH of these apps seem identical and have the same layout and give the same results.. however torress gives different results. which confuses me and makes me wonder which program is giving the true results and which program should i follow? i will post an example using the exact same input data , here you can see torres' result versus the ultimate car audio app results . (I had to use 2 screen shots to fit all the data for the ultimate car audio app)

torres:

ultimate car audio app:

[YukonXL04]

Looks like the difference is in the port volume. That's where your .07 difference is at.

[akuma4u]

So which calculator is more accurate? Maybe if someone has bassbox or winisd or some other more elite program they can plug in the numbers and see what they get?

[YukonXL04]

I usually manually calculate all of my volumes and dimensions then use a simply length calculator to tell my my tuning. Takes all the maybes out of it.

[Joe X]

On 12/20/2017 at 2:27 PM, akuma4u said:

So which calculator is more accurate? Maybe if someone has bassbox or winisd or some other more elite program they can plug in the numbers and see what they get?

 

Here's my calculations for that Torres input:

 

Enclosure Technical Data:

Fb = 41.223 Hz
Vb = 1.702 ft^3

External Height = 13.5 in
External Width = 31.5 in
External Depth = 15 in

External Volume = 3.691 ft^3

Wood Thickness = 0.75 in

Internal Height = 12 in
Internal Width = 30 in
Internal Depth = 13.5 in

Port Width = 3.5 in
Port Height = 12 in
Port Height to Width Ratio = 3.429
Port Cross-Sectional Area = 42 in^2
Port Center Line Length = 32 in
Port Total Displacement = 0.9 ft^3
Bracing Displacement = 0 ft^3
Driver(s) Displacement = 0.21 ft^3
Total Displacement = 1.11 ft^3
Gross Internal Volume = 2.813 ft^3

 

If you mind calculations accuracy I wouldn't recommend Torres, in some cases it is reasonably accurate (like this one) but in others it can go off significantly.

[akuma4u]

On 12/24/2017 at 3:30 AM, Joe X said:

 

Here's my calculations for that Torres input:

 

Enclosure Technical Data:

Fb = 41.223 Hz
Vb = 1.702 ft^3

External Height = 13.5 in
External Width = 31.5 in
External Depth = 15 in

External Volume = 3.691 ft^3

Wood Thickness = 0.75 in

Internal Height = 12 in
Internal Width = 30 in
Internal Depth = 13.5 in

Port Width = 3.5 in
Port Height = 12 in
Port Height to Width Ratio = 3.429
Port Cross-Sectional Area = 42 in^2
Port Center Line Length = 32 in
Port Total Displacement = 0.9 ft^3
Bracing Displacement = 0 ft^3
Driver(s) Displacement = 0.21 ft^3
Total Displacement = 1.11 ft^3
Gross Internal Volume = 2.813 ft^3

 

If you mind calculations accuracy I wouldn't recommend Torres, in some cases it is reasonably accurate (like this one) but in others it can go off significantly

ok so heres the story: i was trying to design a box myself using torres, then while on the go i downloaded some apps on my phone, ct sounds app and ultimate car audio app, both these have the same box calculators on them so i got the exact same results on them but the results (using same input data) were quite off on torres. So this made me skeptical on these premade calculators..

So.. i searched on how to calculate encloses manually and i found this :

 

so, i basically followed these steps except for the first step instead of using the volume the sub needs then later adding the displacements, i used my max dimensions and then subtracted the displacements.. anyhew,  i input all my data.. and with the help of the 12volts port length calculator i arrived at my result. The result is way off torres. But i know torres can be inaccurate.. SO.. what i really need is to someone to go over my steps and/or plug in my input and see what they get on their end to see if my result is correct or not. I have a feeling there may be an error somewhere due to not removing volume for the port thickness walls or something.. i have no idea how to do that.. but anyways here is what i did

MAX dimensions: 13.5 high X 32 x 14.5 wide  (subtract 1.5 from all 4758 then divide by 1728)

BOX GROSS VOLUME= 2.75

12volt port length calculator for slot port: height 12  port width 3.5  VB= 2.75 tuning freq 37hz  RESULT: 24.715915963067893  (WILL round to 25)

port length 25 -.75 = 24.25 x 13.5 height =327.50

port width 3.5 +.75 = 4.25 x 327.50 =1434.37 / 1728 = .80

PORT displacement .80

sub displacement .21

2.75 gross box size - port displacement .80 - sub displacement .21 = 1.74 NET

SO 13.5 x 32 x 14.5  will yield a 1.74net enclosure tuned to 37hz with 42Sq in of port area

DID I MESS UP? please confirm if i did and where etc.. and what calculation i left out

THANK YOU

p.s for those who are celebrating it.. Merry christmas