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.

The tuning frequencies are all listed on greenboy's site, here. The 15/6 is 3.8 cu ft IIRC, I'm sure someone on his forum can give you the rest of the internal box sizes.

+1

Furthermore the plans are posted, a little homeowork and one can work out the volume and porting.

IIRC from the older threads, the 115 tuning is ~47hz before the later optional port extension.

As stated, not hard to reverse engineer it off the plans.

Yeah, I could work them out but I asked because if some one knew it would save me the work and second guessing myself. I was just wondering if someone had done the homework already to spare me the trouble.

Thanks.

its like 3.8 CuFt and 46hz on the 15/6.

and the 12/6?

Yeah. Greenboy did. Follow the links to any info you need.

Oh I forgot to thank you CL400Peavey and Passinwind for taking the time to reply. I do appreciate it.

Thanks again.

No worries; sorry I don't remember the12/6 volume --it's been a few years and I'm on a different computer now...;)

I've looked at all the links many times. The exact internal volumes and port tunings for the various models are not posted anywhere as far as I can tell. Nor could I find them by searching the forums.

Regards.

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.

Hi.

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