I'm using WinISD to calculate an enclosure for my Infinity Kappa 100.3se Driver. It doesn't seem to be going as well as I'd hoped.
First off, the recommended enclosure according to Infinity is 21.24 Liters, but the recommended enclosure on WinISD is like 14.8 Liters, there are a few parameters I left out, but the crucial stuff is in there...
Qts: 0.42
Qms: 6.43
Qes: 0.45
Vas: 27.1 Liters
Fs: 30.58 Hz
SPL: 90 dB
Re: 3.82 Ohms
Le: 2.13
Xmax: 13.5 mm
BL: 15.41
Sd: 320.0 cm^2
I'm just trying to figure out why the difference in the volume recommendations, and which I should use when designing my box, I suppose I'd want it to cut out around 30hz, where I could no longer hear the bass...My amp has no Sub-Sonic filter, so a well designed box would be key to that...
Thanks...
i only use win isd for some small features, like port lenght and the tone generator..I dont use a whole lot on it but i would always go with the manufature's spe'c over that chessy computer program
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2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place
Sealed enclosure, I presume? Plug the manufacturer's recommended size into the project: you'll note the change in QTC, as it goes down from the flat response of .707 as you increase the size. You'll also notice a slight change in f3 as you increase the box size. It goes a couple of Hz lower in the '40s when the box is bigger. It would seem that the manufacturer is recommending the larger enclosure to increase the low end response. Whereas the program gives you the size that will provide a flat response. I'm using the latest version of Pro, and it gives you choices when you set up the project, of type of response you want. You can pick flat .707 or a bass-ier response of .5-something.
There are some other programs you can plug parameters into also. But the math used is all the same across the board, with all of them...even the ones the manufacturer uses. You can look at it like this: the recommendations are meant to cover installation for everybody, from the purist to the basshead. So they necessarily want the average consumer to appreciate the lowest freqs that the sub will produce, without it getting too sloppy. The result is some boominess along with those couple of extra low freqs, but the average listener isn't one who checks it out with calculations first as you are doing. I would say if you are working on achieving SQ, you look at the graph on WinISD for the varying sizes and make a determination based on that.
Another thing, it wouldn't hurt to email tech support at Infinity and ask about that, also.
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.