Re: T/S parameters and Box Design w/ WinISD
Parts Express uses Bass Box to model and they use the high fidelity setting. WinISD models, by default, to fit the driver with no respect to common physical limitations.
On a number of high powered, high xmax subs I've modeled with WinISD it recommends outrageous box sizes, sometimes upward of 40-60 cubic feet for one 12, etc.
If you're getting recommendations that don't look right to you, double check the TS parameters if you entered them manually. And if you're still getting odd recommendations change the box until you get the curve you want and don't worry what other box modeling programs recommend, because each is designed in a slightly different way and with different goals in mind.
At least, that's what I've done and I've been using WinISD for about a decade with much success.
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