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Vb and Fb of DIY fEARUL cabinets?

Hello,

As these are posted DIY projects I don't think this is proprietary information. I've looked and looked but it doesn't seem as if they have been posted. Has anyone worked the internal volume and port tuning numbers out? I'd like to be able to model them in winISD.

Thanks.
 
What are you trying to do?

FWIW the model isn't going to match the actual tuning of the box = long shelf ports are somewhat dodgy, so it can only get you in the ballpark - and the spec already does that. So you either believe the spec tuning - or you build and measure the box to establish the actual tuning. Modeling the box won't change the actual tuning - or the spec. - thus its an exercise in futility.

But if you really want to go there - use the Sketchup model and a volume calculation plug-in should get you very close - then just factor in the reductions in cab volume from the woofer and tweeter and port - if you are careful about process you could generate a measurement probably more accurate than anyone else ever bothered to make. Then plug it in the model - and your tuning calc. will still be wrong [close but wrong].
 
I calculated volume for the 12/6 cube using Excel, accounting for every brace, etc. but not speaker structure volume. I was actually trying to calculate the raw wood weight based on different plywoods so I needed to know the volume of the wood used. The calculation of internal volume was just a convenient byproduct. I made a few backtracks and mistakes along the way, could still be some lurking about but I got 2.23 cu ft.

These are marine plywoods. I have no idea how these weights compare to actuals.

Code:
Carcass weight (lb)
~~~~~~~~~~~~~
Okoume : 20.3
Eurolite IP : 19.1
Doug. Fir Marine : 23.0
Sapele : 25.4
 
Hi.

I'd like to be able to model them in winISD.

Why?

You'll only be able to model the drivers separately, and that practically gets you back where you started.

Without factoring the cross-over and the driver locations in, all You're going to end with is a ballpark idea about the porting.

For a someone who's built cabinets, reverse-engineering the dimensions would be pretty easy, but since all the legwork is already been done, why bother?

Regards
Sam