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View Full Version : T/S parameters and Box Design w/ WinISD



Trey803
09-20-2013, 12:25 PM
I have a Dayton 8" Reference HF subwoofer that I am trying to design a box for.

My problem is that I am not able to find manufacturer box specs. Partexpress.com recommends a sealed box of 0.55 ft^3

When I put the T/S parameters into WinISD, the calculated box volume is just over 1.1 ft^3 for a sealed with Qtc of 0.71


Any clues as to why partsexpress.com's recommended box and WinISD are around 50% different?

Reading the reviews for this sub, some people are going as small as 0.4 with poly-fill, while parts express recommends a vented box volume of 1.76 ft^3.


I realize a vented box tuned to 30 hz will be much larger than sealed but I've never seen such a large range of recommended enclosure sizes for one particular subwoofer.


Would anyone be willing to run my T/S parameters through some different software?

bbeljefe
09-20-2013, 12:41 PM
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.

hispls
09-20-2013, 12:53 PM
Most of the items you can buy at PE have comments section where various users post their experience with different applications. Did you browse that? Seems a common enough sub that there should be plenty of people who already did the testing for you.

Trey803
09-21-2013, 10:14 AM
Yes I have.

Comments range from a guy running sealed 0.4 ft^3 with poly fill....to someone running 1.4 cubes sealed

Quentin Jarrell
01-14-2014, 11:26 PM
I recommend going to Vance Dickason's website and emailing him for his free program pack. It'll help you out a bunch.