Triticum's Improved Port Area Calculator

[Triticum Agricolam]

14 minutes ago, DLHgn said:

I did 11 more test with a different sub and the results change dramatically. The optimal port area now results in a a velocity in the low 30s while the minimum results in a velocity in the low to mid 40s. 

 

1 hour ago, DLHgn said:

So here's what i've found. Optimal seems to get port velocities in a range of 23 - 25 m/s. Minimum gets the velocities in a range of 32-33. By no means have I done extensive testing with different situations but I did 12 tests. I can do some more at another time to push the numbers more towards the extremes on both ends. The calculator so far seems to be pretty consistent which is definitely a good thing. 

Note: Test were done by using Triticum's calculator and comparing the port velocity graph of the Optimal, Minimum and a control port area. If I can find a way to keep people from changing the document I will post a link so y'all can see the actual numbers. 

Thanks for doing some testing.  This is my first shot and this and I may need to change my multiplication constants a bit.  I'm shooting for as close as I can get to 22 m/sec for the "Optimal" number, 30 m/sec for the slot port minimum and 32 m/sec for the aero port minimum.  

If you let me know what configuration is getting you results much different than that I'll see if I can replicate it and make adjustments if needed. 

[Triticum Agricolam]

39 minutes ago, Kyblack76 said:

and can this be used in anyway with a pass band?  and or band pass ?

It SHOULD work with bandpass boxes.  

I want to reiterate that I don't intend my calculator to replace using real box simulation software, simulation software is always going to give the most accurate results short of actual real world testing and adjustment.  What I intend my calculator to be is a easy replacement for when people spout off the "slot ports should be 12-16 sq in per cube" guideline, or for people who can't/won't/aren't going to use simulation software anyway.  That guideline is like a broken clock, its right twice a day, my calc should always be at least as good as that is though and 95% it should give a better result.  

[DLHgn]

37 minutes ago, Triticum Agricolam said:

 

Thanks for doing some testing.  This is my first shot and this and I may need to change my multiplication constants a bit.  I'm shooting for as close as I can get to 22 m/sec for the "Optimal" number, 30 m/sec for the slot port minimum and 32 m/sec for the aero port minimum.  

If you let me know what configuration is getting you results much different than that I'll see if I can replicate it and make adjustments if needed. 

For the sub I used a B2 IS12v3. The link can be found here.

http://www.b2audio.com/is

All other info is on this spread sheet

https://docs.google.com/spreadsheets/d/1KqDTURiuumMMO3uI_UCkyFxEj5t0Y-Vw3-YVsYiSFWc/edit?usp=sharing

[Triticum Agricolam]

1 minute ago, DLHgn said:

For the sub I used a B2 IS12v3. The link can be found here.

http://www.b2audio.com/is

All other info is on this spread sheet

https://docs.google.com/spreadsheets/d/1KqDTURiuumMMO3uI_UCkyFxEj5t0Y-Vw3-YVsYiSFWc/edit?usp=sharing

Perfect, thanks! 

[Triticum Agricolam]

12 minutes ago, DLHgn said:

For the sub I used a B2 IS12v3. The link can be found here.

http://www.b2audio.com/is

All other info is on this spread sheet

https://docs.google.com/spreadsheets/d/1KqDTURiuumMMO3uI_UCkyFxEj5t0Y-Vw3-YVsYiSFWc/edit?usp=sharing

So I replicated the test you did, for the Mayhem 12 I get exactly the same results as you do.  But for the ISIS I do not.  I usually get right around 31 m/sec for the slot port minimum, and right around 23 m/sec for the optimal port area.  
I wonder what's different between our two tests?  Is it possible you didn't change the port from round to rectangular in WinISD?  

[DLHgn]

1 minute ago, Triticum Agricolam said:

So I replicated the test you did, for the Mayhem 12 I get exactly the same results as you do.  But for the ISIS I do not.  I usually get right around 31 m/sec for the slot port minimum, and right around 23 m/sec for the optimal port area.  
I wonder what's different between our two tests?  Is it possible you didn't change the port from round to rectangular in WinISD?  

I was definitely on square port. Maybe it's the parameters of the sub? I could've put them in wrong. Could you screen shot the parameters you have for the sub in WinIsd? 

[Triticum Agricolam]

1 minute ago, DLHgn said:

I was definitely on square port. Maybe it's the parameters of the sub? I could've put them in wrong. Could you screen shot the parameters you have for the sub in WinIsd? 

Sure can.

 

[DLHgn]

I'm not sure what happened. The only thing really different is my Re and number of voicecoils. The IS12 has 2 voice coils and I used the dual 2 ohm version but besides that everything else is the same. I actually just noticed my Vas is twice what yours is for some reason. I manually entered the Qes as .59 but the Vas goes to 66.42. If I let the Qes autocalculate it goes to .295 and Vas goes to 33.21.

[alaskanzx5]

just used it. im aiming for 80-100" port area ( slot port ). the calc said i need a min of 90 and optimal of 123. 

thats a 7.5 net box, tuned to 32-35hz with 3k watts. 

dont know if it was asked but what about xmax? sub size?

dont those play a factor in port size? i mean with the higher xmax and larger subs you can potentially move more air.

[Triticum Agricolam]

41 minutes ago, alaskanzx5 said:

just used it. im aiming for 80-100" port area ( slot port ). the calc said i need a min of 90 and optimal of 123. 

thats a 7.5 net box, tuned to 32-35hz with 3k watts. 

dont know if it was asked but what about xmax? sub size?

dont those play a factor in port size? i mean with the higher xmax and larger subs you can potentially move more air.

I know it seems like Xmax and sub size should matter, but really they don't.  I commented on those things further in post #30, you can see it if you click here.