How to calculate volume of waterdrop shape

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Where do you buy this waterdrop shaped stainless steel vessel or is it custom made? Egg shaped studio monitors made of stainless from Eclipse sell for like $10k with a 4 inch full range driver. It would be cool to find a low cost diy way to do this.

Egg-shaped studio monitors from sE cost $2.5k.
They are active 2way with a 6.5" woofer and outboard electronics. All designed by the same guy who did the Dynaudio monitors.
Not made of stainless steel though.
 
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Egg-shaped studio monitors from sE cost $2.5k.
They are active 2way with a 6.5" woofer and outboard electronics. All designed by the same guy who did the Dynaudio monitors.
Not made of stainless steel though.

$2.5k? No thanks but I can build something that sounds pretty good and measures nicely for $11 :)

387592d1387034655-foam-core-board-speaker-enclosures-teardrop-5-final.png


Albeit, only goes to 150hz so needs a helper sub.
 
They will be custom made, and the stainless steel will be 1.2mm thick.

How would the ultimate bracing look like?, because i could brace the speaker before it would be fully sealed. Maybe only two metal pipes welded is enough, but instead of have them in the middle as a cross its maybe better to have the two pipes at half way to the middle of the speaker cabinet if you understand what i mean.


Im also thinking about where i should place the binding post, what i see is two alternatives either just under the "arm" that holds the speaker or at the end where it is tight but then the cable and binding post need to be placed there before it will be sealed.

Diameter at the widest if 28cm, so it shouldnt be any problem to fit a 6.8inch driver or what do you think?

It will be 71cm in length. And with stand+arm+speaker box i will try to get 29-30cm up to the center of the full range becasue then the speaker will be at a height of 90cm with a 60cm speaker stand.
 
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Picture of how it will look.

The arm will maybe be little longer and the stand will be made of another material.

Please give me tips about internal bracing, the binding post i think i will put 30cm from backend so its possible to reach the binding post from driver hole.

drop with base real - Ladda-upp.se

This is how I braced the inside of my speaker - 3 braces in hexagonal arrangement. Your wall thickness is probably thick enough for no brace.

387590d1387034655-foam-core-board-speaker-enclosures-teardrop-2-brace.png
 
When i use a program for a sealed box with the speakers spec then i get 33.4 liter.

This is the calc
mh-audio.nl - Home

Fs: Is it say as Fo? I wrote 45hz
Qts: 0.521
Vas: 28.108l

Then i get 33.4l, is it so easy to get which sizes only on these specs?

Maybe 16.5l is much to small, but if i make it little ported at the end, lets says 2cm open at the end, would it help so i wount need to make it bigger? Or maybe i should go for 18-19l or something.
 
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Use a program like WinISD and you can enter the parameters and calculate the ideal volume and port size. If your volume is less than ideal - you can see what the response will be like. 33 liters is a little over 1 cubic ft - a good size chamber. If you are running sealed, having it smaller is not a big deal if deep bass extension is not a primary consideration (which I assume it is not as sealed boxes are used for their clean transients at expense of bass extension). You have to use a program though if you want to have any hope of having a well-designed ported enclosure. With sealed, it is OK to be off a bit.
 
I installed WinISD for not so long ago, and for sealed there i get 32.64 liter for closed box. But the manufacture states 16.5l, but i will need to check if thats ported or closed, the manufacture should know whats the best size would be for sealed.

If i make the shape 30cm in diameter at the widest instead of 28cm and 72cm deep, then the will have 20.5l instead of 16.5l maybe 2cm more in diameter should be better or what do you think?


I just use this program
and choosed 0.001 for closed box on vented as explained and at 16.5l i got Resonance frequency at 0.87hz?
 
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I just ran WinISD with your driver parameters and the smaller 16.1 liter volume gives deeper bass extension in a sealed box. The bass is flat down to 100 Hz and falls -5dB by 50 Hz. WinISD picks a volume that gives a more gentle roll-off slope but with less bass extension. If your chamber is already 16.1 liters - stick with it, you are not gaining anything by going to 32 liters.
 
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