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WinISD help - missing parameters

post #1 of 12
2/14/08 at 9:12pm
Thread Starter 
I'm struggling to input my own driver into WinISD. I have the PDF file with some of the T/S parameters; but a few are missing. Is there any way to figure these out mathematically?

Below is what I have to work with:



WinISD asks for much more information than the above offers - what are the minimum required fields for the program to function properly? Using only the above parameters gave me vastly difference sealed and vented enclosure volumes than recommended by the manufacturer.

The sub is a 12" OZ Audio Power Matrix.

Thanks!
Dave
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post #2 of 12
2/14/08 at 9:23pm
if this is for HT forget it-Fs too high IMO.
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post #3 of 12
2/14/08 at 10:37pm
I had the same problem. I used this website and used the ported software layout. You can pick from bandpass, ported, or sealed. http://www.ajdesigner.com/speaker/index.php
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post #4 of 12
2/15/08 at 2:03am
from the Help file:

The suggested procedure for entering driver parameters is following (check first that "Auto calculate unknowns" option is checked):

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.
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post #5 of 12
2/15/08 at 11:10am
Thread Starter 
Quote:
Originally Posted by mayhem13 View Post

if this is for HT forget it-Fs too high IMO.

Really? Why is that? The sub was previously used in my car, but now I wanted to get a sub set up in the HT for cheap.
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post #6 of 12
2/15/08 at 11:10am
Thread Starter 
Quote:
Originally Posted by zero the hero View Post

from the Help file:

The suggested procedure for entering driver parameters is following (check first that "Auto calculate unknowns" option is checked):

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.

Great, thanks! I will try that.
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post #7 of 12
3/8/08 at 3:33pm
Thread Starter 
I'm still struggling to figure out what size box to put this sub into. Can anyone help me figure this out? I'd really like to try it out instead of buying a new woofer.

Thanks!!
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post #8 of 12
3/8/08 at 3:42pm
Thread Starter 
Here are a couple pics of the sub I've got - this thing should have some serious excursion! (Which is why I want to use it - the mfg. claims 3" peak-to-peak... )



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post #9 of 12
3/8/08 at 5:49pm
Dave, I ran some numbers to see what it would look like in a sealed box. It's not good! F3 > 70hz at Qtc of .707

With an EBP [efficiency bandwidth product] of 93.9, it's definitely a candidate for ported. The good thing is Vas is very low, so the box won't be very big. Probably will work in a EBS3 / LLT type box. Mayhem is right. I wouldn't buy one, but since you already have it, it's worth a shot.

I suggest you email OzAudio and ask them for the T/S parameters.
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post #10 of 12
3/14/08 at 7:48am
Thread Starter 
I've emailed Oz Audio with no response. Warmon suggested I try the sub in a 2.5-3.0 cf ported box - but I'm not sure what to tune it to? I have a 240w Plate amp and 4" Aeroport arriving today and I'd like to build a box over the weekend for it. The mfg. sheet suggests a 1.5cf ported box with a 4" port, 15" long. That seems incredibly small - they claim the Fs will be 27hz (which isn't terrible). If I built a box with 3.0 cf, using a 18" long 4" port, I should be able to tune it to 23hz. Does anyone have any recommendations on what to try?

Thanks!
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post #11 of 12
3/14/08 at 9:21am
Quote:
Originally Posted by dykz34 View Post

I've emailed Oz Audio with no response. Warmon suggested I try the sub in a 2.5-3.0 cf ported box - but I'm not sure what to tune it to? I have a 240w Plate amp and 4" Aeroport arriving today and I'd like to build a box over the weekend for it. The mfg. sheet suggests a 1.5cf ported box with a 4" port, 15" long. That seems incredibly small - they claim the Fs will be 27hz (which isn't terrible). If I built a box with 3.0 cf, using a 18" long 4" port, I should be able to tune it to 23hz. Does anyone have any recommendations on what to try?

Thanks!

If you plug in the parameters they give and guess 480 cm2 for the SD the rest of the parameters are filled in by winISD. This probably isnt super accurate, and the SD is probably a little less than 480 with that big of a surround.

That said, using those parameters winisd suggests a 2.2 cubic foot box tuned to 21hz for an EBS6 box. You'd be -7db at 20hz. Vent length would be 32 inches for a 4" port.
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post #12 of 12
3/14/08 at 3:23pm
Anybody know if the PE 240w amp has a high pass and what it is? I'm not really a ported kinda guy...the best I can do with it is 2.75cf, 23hz tune, 6" vent @ 47.8". It's -5.5db at tune and drops like a rock below that.
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