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garychurch84

Port Calculator?

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Download WinISD. You'll learn a crapton in the process. Before trying to enter the Zcon though Google how as it is really critical of rounding "errors".

In quotes as they aren't all that significant, but WinISD will see them as wrong.

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The only other method I'd use is hand calculations. Grab Dickison's book, it's worth it. Buy an old version for cheap wink.png The math hasn't changed.

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The only other method I'd use is hand calculations. Grab Dickison's book, it's worth it. Buy an old version for cheap ;) The math hasn't changed.

I have WinISD,but it don't work right it seems to me. May need to install it again.

I was googling how to do it by hand when I found those lol

Thx M5

Edited by garychurch84

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Be sure to get the newest version of WinISD (version 0.7.0.900) its much better.  You can get it here: http://www.linearteam.org/download/winisd-07x.exe

 

When you try to enter in the T/S parameters of your sub, you will have a lot better results if you do it this way: 

 

1. Enter Mms and Cms
 
This gives fs. If either is not available, then enter fs and other parameter.
 
2. Enter Sd, Bl and Re
 
Now, you should get all but Qms (and Qts), Vas. Please note that Vas may not match exactly what is specified by manufacturer, because exact value of Vas depends on environmental parameters. See FAQ.
 
3. Enter Rms or Qms.
 
Either one will do, although I tend to prefer Qms over Rms, because it can usually be measured in driver measurement procedures.
 
4. Enter Hc, Hg and Pe.
 
If Hc or Hg or either is available, then enter Xmax and optionally either Hc or Hg if available.
 
5. Enter number of voicecoils.
 
This procedure is most accurate. Also note that it also calculates true SPL (1W/1m) value. So it might not match the marketing SPL value, which is generally somewhat vague. Not in all cases, though.
 
6. Correct Znom, if necessary.
 
If there are several voicecoils, then you must be careful when entering parameters in that case, because many manufacturers give Bl in voice coils in series, because it yields double value for Bl against parallel connection. If driver manufacturer gives Qes, Bl and Cms or Mms, then you can check how Bl is specified. For that, you can enter following parameters to calculate Re: Qes, Fs, Mms or Cms and Bl. Connection mode can be changed by changing the combobox selection. The driver editor then converts Bl and Re values accordingly.
 
Equivalently, you can check for Bl by entering:
 
Qes, Fs, Mms or Cms and Re (for desired connection mode).
 
If you enter resistance for parallel connection and get about half of advertised Bl, then you know, that Bl was specified that way.
 
Like in Driver-tab in project window, you'll probably noticed the driver icon in bottom of the driver editor window. you can drag the driver object into some project by just dragging the icon.

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I've never seen a version not work right.

NEVER EVER use "optimal" as your design though. You must manually put in the iterations you want and then review the response curves to make sure they meet your expectations.

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I've never seen a version not work right.NEVER EVER use "optimal" as your design though. You must manually put in the iterations you want and then review the response curves to make sure they meet your expectations.

I'll try the steps mentioned above an see where that gets me

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I've never seen a version not work right.NEVER EVER use "optimal" as your design though. You must manually put in the iterations you want and then review the response curves to make sure they meet your expectations.

I'll try the steps mentioned above an see where that gets me
In a box biggrin.png

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I also use WinISD, but find the WinISD and Carstereo are very close once you figure out the port area and net volume you wish to use.

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It is pointless to use ANY calculator that doesn't show response graphs. Exception being if you are just building to a manufacturers specific box...but I haven't been able to do that in 20 years lol

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Personally I like to calculate myself over any current enclosure software if at all possible IMO.

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I've never seen a version not work right.NEVER EVER use "optimal" as your design though. You must manually put in the iterations you want and then review the response curves to make sure they meet your expectations.

I'll try the steps mentioned above an see where that gets me
In a box :D
There it is!! Lol

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I've never seen a version not work right.NEVER EVER use "optimal" as your design though. You must manually put in the iterations you want and then review the response curves to make sure they meet your expectations.

I'll try the steps mentioned above an see where that gets me
In a box biggrin.png
There it is!! Lol

 

X2.lol

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