I am currently having a new countertop made for my kitchen by a local contractor here in northern CA. He specializes in concrete and terrazzo and has been working with this material for a long time. It came up in a conversation that he is looking to expand his product offerings beyond kitchen a bath products and after awhile we started talking about speaker cabinets. He is currently developing molds for mass producing sinks and bathtubs and I we came up with the idea that he could make a mold for a speaker cabinet. This could be something similar to the Parts-Express removable baffle, curved back cabinets except done in a single color or terrazzo style (with ground-flat and polished inlaid stones, marble chips, mother-of-pearl, etc) concrete. The quality of his work is really excellent and he can also do custom work on a case-by-case basis.
I offered to put out a feeler here at DIYaudio to see if people are interested in this kind of product, what size might be a good first effort for him, and so on.
If you are interested in something like this, please post a reply with your thoughts.
I offered to put out a feeler here at DIYaudio to see if people are interested in this kind of product, what size might be a good first effort for him, and so on.
If you are interested in something like this, please post a reply with your thoughts.
It's out on the coast in Sonoma county. There is a cool art culture here and he is part of that. But he is also trying to earn a living and there is only so much clientele in the immediate area. He can ship anywhere in the USA.
Was thinking more like 20 liters and wide enough to accommodate an 8" woofer and possibly with the sides curving inwards. The exterior surface is polished smooth and sealed. The cabinet would come without a baffle so that the user could route a wood baffle for their drivers and then install it. At least that was what I was envisioning.
Obviously the weight will not be insignificant and the shipping cost needs to be considered. As you suggested a very small cabinet would help keep shipping costs to a minimum, but I am not sure how much demand there would be for a very small cabinet. But I am certainly open to input and if that is the size that has the most interest we would start there. That would lower the cost hurdle for people who wanted to try it out... on the other hand I am not sure how the manufacturing costs scale with volume. This will all have to be figured out I guess.
Depending on what is used for the inlay the terrazzo material can be really striking and would be a really beautiful piece to put up front and center in one's living space.
Attached is an example of the "terrazzo" inlaid material in a neutral background cement matrix. You can choose both the cement color and the type and character of the inlaid material. This is a pic of the first 12x12" sample he made for our countertop job. It hasn't been sealed and polished yet. The final surface will be reflective, like polished granite.
Attachments
A couple things-
1) Cool!
2) I'd have metal threaded inserts in the material for baffle mounting, and have the baffle inset with a large roundover made of the cast material
3) Damping will matter, as hard materials like these will tend to ring. I'd make a point of incorporating a resin or other component into the mix, something I've had success with when using plaster cloth
1) Cool!
2) I'd have metal threaded inserts in the material for baffle mounting, and have the baffle inset with a large roundover made of the cast material
3) Damping will matter, as hard materials like these will tend to ring. I'd make a point of incorporating a resin or other component into the mix, something I've had success with when using plaster cloth
Bigger than any of my favorite drivers work in
7-10 litre covers off my favorite driver.dave
There is a local Lunatic who builds Bespoke Flowerpots /Planters from concrete.
It took him almost 3 years of Dicking about experimenting to develop his technique.
Yess Flower pots ..Urns etc All heavily decorated, Think Wedgewood and Cast Iron from the Victorian era stylings.
Exquisitely done with Zero airbubbles/ voids
All come out of Silicone Molds and wall thicknesses are in the 3/4" to 1" range
Concrete is of snow white or coal black Buyers choice.
His Concrete Matrix is a self developed blend of Plastics.. Yup!
These sell from 200$ to 2000$ ..each. And there is a constant wait list.
Perhaps your Cement guy might consider a product market where the Buyers are plentiful/increasing and passably wealthy.
Neither of which applies to DIY speakers
It took him almost 3 years of Dicking about experimenting to develop his technique.
Yess Flower pots ..Urns etc All heavily decorated, Think Wedgewood and Cast Iron from the Victorian era stylings.
Exquisitely done with Zero airbubbles/ voids
All come out of Silicone Molds and wall thicknesses are in the 3/4" to 1" range
Concrete is of snow white or coal black Buyers choice.
His Concrete Matrix is a self developed blend of Plastics.. Yup!
These sell from 200$ to 2000$ ..each. And there is a constant wait list.
Perhaps your Cement guy might consider a product market where the Buyers are plentiful/increasing and passably wealthy.
Neither of which applies to DIY speakers
DIY speaker builders, I suspect, have higher than average education levels and incomes. I don't disagree with your conclusion (not a great market), but in my experience most DIYers are in their 40s-50s and are reasonably well-to-do. The tools, time, etc, are not as accessible to people of low income, naturally, there are some exceptions.
But for this kind of thing, there is precedent that should be something of a concern- look at the autotech horn ordering from diysoundgroup. They order things on a one off basis for most models. The market simply isn't that large, and while diyers may have decent incomes, many are very frugal about the parts used, valuing getting great sound from more modest part investments. A product offering in the mid-size bookshelf range is probably best, but there are many for whom that's too small a speaker for their preference.
But for this kind of thing, there is precedent that should be something of a concern- look at the autotech horn ordering from diysoundgroup. They order things on a one off basis for most models. The market simply isn't that large, and while diyers may have decent incomes, many are very frugal about the parts used, valuing getting great sound from more modest part investments. A product offering in the mid-size bookshelf range is probably best, but there are many for whom that's too small a speaker for their preference.
Hmm, if a poll on income and edumatcation levels were politically correct, I think you'd find the results interesting
So perhaps the best approach is a run of small-ish (10 liter?) cabinets that are too small to ring much and not so heavy that shipping costs are unaffordable. Then if people want something custom/larger/oddly-shaped that can be done on an individual basis. The guy can fabricate more or less any shape that you can make with a pour process and a mold. How about a sphere? Can do. Curved baffles, sides, etc.? Can do. But these more complex options would be much more expensive and done on a custom basis. On the other hand, the production box can have curves and something that you just cannot do very easily in wood might be nice to set it apart. For example a racetrack-oval shape.
I don't think that including a few threaded inserts (e.g. to hold on a baffle) will represent a problem. DIYers can usually prepare their own baffles. On the other hand a rebated baffle out of terrazzo that is customized to a particular set of drivers is getting into the low volume custom work unless there is a group buy arranged or something like that.
I don't think that including a few threaded inserts (e.g. to hold on a baffle) will represent a problem. DIYers can usually prepare their own baffles. On the other hand a rebated baffle out of terrazzo that is customized to a particular set of drivers is getting into the low volume custom work unless there is a group buy arranged or something like that.
Molds are made from foam and fiberglass. Remember, the mold is then used to make many, many identical items. Machining an ALU block makes one.
Remember this is not really about the material (concrete) being better than aluminum or whatever. It's more about the amazingly beautiful surface finish of the terrazzo material and the fact that a mold can be used to consistently reproduce the shape. Also, while the shape would be fixed by the mold itself, the color of the cement and inlay can be varied greatly to the preference of the end user, for instance to match decor or to give it a certain look.
Another option would be to make a DIY copy or at least take design cues from a famous speaker and do some key parts in the terrazzo concrete.
How about something based on the B&W 801?
The concrete part could be the ball and its plinth (slanted top of woofer cabinet) that contain the midrange and tweeter. The DIYer would build the rest out of wood.
An 801 inspired DIY speaker using current drivers would be a pretty cool project!
How about something based on the B&W 801?
The concrete part could be the ball and its plinth (slanted top of woofer cabinet) that contain the midrange and tweeter. The DIYer would build the rest out of wood.
An 801 inspired DIY speaker using current drivers would be a pretty cool project!
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What about an egg (think Waveform) that could be used as a mini monitor or the "head" of a 3-way?
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