Ceramic Speaker enclosures

In the past year I have become skilled at throwing forms on the potter's wheel. I want to make a speaker enclosure out of clay.
The ideal shape of a speaker enclosure is a shpere. I could make a round shape easily on the wheel, make a perfectly flat space to mount the driver at top, and presto! I have a round speaker enclosure. I can stand it on some legs so the woofer faces forward. I can even make a little enclosure for a tweeter or mid, attatch to two shapes, and stagger for time alignment. Many possibilities. What do you think?
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bostarob said:
The ideal shape of a speaker enclosure is a sphere.

Close but not quite. Good for diffraction on the outside but a single resonance on the inside. An egg is a better shape. Even better is if only the front is a sphere or egg and the back tapers away to a point. Like the B&W Nautilus, or the Norh mentioned, or like the shapes of the cars Bucky Fuller drew. There is a thread on this forum (i think it is here) where the shape, after much trial & error, ended up being an 8 sided approximation of a half-sphere teardrop shape.

Still doable as thrown pottery -- i have a flower vase that would be perfect for a 2' driver.

The most difficult problem that I can forsee is shrinkage of clay. Clay can shrink up to 15% during drying and firing. I will need to compensate for this.
-egg shape
sure, sounds great
-nOrh speakers
wow! Interesting shape. They threw a shape that looks like a wine bottle with a hole in the bottom. excellent idea, I was thinking of throwing something that looks like a teapot without a spout, and mounting the driver on the bottom.
What is an inverted horn?
Yes, clay certainly does have a ringing quality to it, but that is easily overcome

Does anyone have any ideas for mounting drivers? T-nuts? Ha!
Once clay is fired, one can drill a hole using a glass/tile drill bit.
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bostarob said:
Interesting shape. They threw a shape that looks like a wine bottle with a hole in the bottom. excellent idea, I was thinking of throwing something that looks like a teapot without a spout, and mounting the driver on the bottom.

Here is a picture of the ceramic i have that suggests a good shape.

An externally hosted image should be here but it was not working when we last tested it.

I wouldn't flatten quite so much of the bottom part of half-sphere, and i'd stretch out the taper in the top half.

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Read a review of a spherical ceramic enclosure a decade or more ago. The reviewer also said that a sherical enclosure was not the ideal.

The reiviewer cited the fact that half sperical ceilings of buildings do not make for great acoustics.

Experimenting with a 4" sounds like an entirely sensible idea.

Good luck with your project that combines two interests.
This beautiful shape made by young Danish designer is not made of clay but some kind of wood composite. He had another enclosure on their web page some time ago: three differently sized and stacked spheres shape - prototype made of china . Unfortunately he doesn’t show this any more. Shame- it looked even more gorgeous IMO.


An externally hosted image should be here but it was not working when we last tested it.
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There was a company named Waveform that was rated A in stereophile.

They had a conventional woofer, but the mid and tweeter
were in an egg shaped enclosure on top.

The egg had the pointy side up, the front was flattened, and it had a midrange low on the fatter part with a tweeter right above it.

The shape was lined with damping and absorptive materials.

Epoxy would work as glue I would think.

But with the above design, If you flattened the front, and poked holes where the bolts would go before firing, You could attache the drivers with bolts, rubber washers under the headsand nuts,
rubbere gasket between the egg and driver. I know the hole would shift a bit, but you could make them biggerthan the bolts.

Also experiment to seehow they distort and compensate.
The dimaxion driver? Why not. A good clay to do this with if you can fire high enough would be industrial porcelaine. I have some beautiful raku a guy in Wisconsin made with it. He looses less pots because of the strength. Of course once you refine your shapes it would be a good idea to make molds so that you can be consistant. Keep that in mind as you you work on your shapes. It might be better to elongate a bit for the interior volume than working with an onion shape to facilitate mold making. A driver that comes to mind is the Tang Band W3-31951 3"er. I heard a pair that were in cast enclosures( looked like white epoxy ) about the size of an old Minimus 7 with a port about 1/2 wide and 3/4 in deep. Although I couldn't see the inside I doubt is was spherical though the inside corners were probably rounded. Amazing presence! Low cost from China.
so i'm sittin here reading this thread and thinkin about all these weird shaped flower pots my friend has at his nursery and then i see where david mentions porcelaine and i remember that theres these two old toilets sittin behind the shop at work and i have some drivers around here that would fit and after i put em together how can i make them not look like toilets so my wife will let me put then in the den, could be fun...............

Toilet speakers would be great

The clay I'm using shrinks so much that any holes I would make before firing would be useless

So you think epoxy would work? What about polyeurathane glue?

I threw the prototype today, its not very good looking, but oh well. It looks like a bell, the woofer is going to be mounted on the wide side. I also make a cylindrical stand for it that will be filled with sand. What can I line the inside of the enclosure with to keep it from ringing like a bell?

Porcelain in a Raku firing? odd, normally you'd use a clay with more impurities, like a raku clay. The raku firing process also significantly weakens pottery, especially if the walls are thick(they tend to crack). I will be using a cone 6 (2300• F) high fire. The clay I am using is similar to porcelain in the impurity level and strength. It will have a prominent ring, I am sure.

Oooo, I just read Dave's suggested link, one of those guys uses liquid nails to mount baffle to pot. He's gotten all of his pots from home depot, but I can make them look pretty nice. Dampens resonances with vinyl flooring bonded with liquid nails. He speaks very well of them:
"How do they sound ? ***They DONT!*** All u hear is the characteristic sound of each driver in lovely isolation ! I have never heard better !"
I am excited!
I'll try to post pictures
Only time I have ever seen porcelain raku, but great thin shapes and the copper oxides are freakin beautiful. Reason I thought of it was the the equal thickness of the sides for most of the height, the great strength and the fact that there would be only one standing wave the chances of additional harmonics from the structure ought to me minimal. A bit of fiber stuffing ought to take care of all that. Maybe you ought to think of raku....you would be the first to ever do that! Baking people to a cone 6 was a common threat in school. Don't touch that!!!!
I was just thinking of the looks of the speakers. Say you made a 3 way with a pot for each driver, how would you present it. I was thinking of the basic shape of the drum and the the Avant Garde 3 way horns, and glazes. <www.avantgarde-usa.com> Take a look at the horns, think of the shape of the pots, and how cool the opalescent copper oxides of raku would look. Nobody has ever done such a thing that I know of and I thought you might like the idea. I don't throw anymore otherwise I might give it a stab myself.