Comments on: Concrete cast speakers

By: wholesale merchandise

wholesale merchandise — Wed, 18 Feb 2009 03:08:48 +0000

Very interesting idea. You could probably cast the concrete speakers in different shapes than the usual rectangle.

By: rich

rich — Wed, 14 Mar 2007 00:13:05 +0000

I built a sub with dual 15 ” yamaha accordian surround paper cone speakers using 2″ thick concrete poured into all sides of a divided particle board box/w 4″ ports. at first i stuffed the boxes with baffling material,the bass was so low we couldnt hear it,yet it shook the entire house. When we took the baffling out we could actually hear the bass which was incredible. Concrete can also be used as a base to mount your high frequency drivers. Using spiked feet this can reduce unwanted transfer of vibration from the low frequency drivers. Email rjjc1929@yahoo.ca for more info.

By: JoJO

JoJO — Sat, 10 Mar 2007 06:37:42 +0000

If it was me, I would not use wax. Make what you want to dissappear out of styrofoam and then later just pour in a solvent to make the foam melt away. And for the concrete to be lighter use 1/3 pumice.
I make things in concrete all the time.

By: thomas

thomas — Fri, 02 Feb 2007 14:47:09 +0000

I realize the molds would have been more complex, but he could make the speakers any shape he wanted so he chose to make them look like conventional ones?

By: weirdcrap

weirdcrap — Mon, 29 Jan 2007 17:39:40 +0000

for anyone who is interested in the writing on the site here is a google translation link

http://translate.google.com/translate?hl=en&sl=de&u=http://propirate.net/betonboxen/&sa=X&oi=translate&resnum=1&ct=result&prev=/search%3Fq%3Dhttp://propirate.net/betonboxen/%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26hs%3DWcD

By: dan

dan — Thu, 25 Jan 2007 23:08:20 +0000

It’s a big shame you painted them!! They looked a LOT better with the raw concrete look. Why hide the fact they are concrete – that’s the whole point!

By: Sammy Taters

Sammy Taters — Wed, 24 Jan 2007 08:31:29 +0000

So the point of this is to stop sound waves from losing SPLs to your cabinet, and force them outward instead….but what about the driver physically touching the conrete? What material is that.

I dont think this is going to sound much better unless his drivers are perfect.

By: headbonk

headbonk — Tue, 23 Jan 2007 19:09:39 +0000

When I first read the title, I thought it said Concrete Sneakers.

I thought it was some kind of a take on a ganster thing… =P

By: Undefinition

Undefinition — Tue, 23 Jan 2007 16:43:24 +0000

The reason you would make concrete speakers is the same reason Medium Density Fiberboard is the material of choice for speakers: very little resonance. In a guitar or violin (or a drum, for that matter) resonance is good. But in a speaker, the only thing resonating should be the driver itself, and the air inside the cabinet. If the walls of the cabinet resonate, you will get unwanted muddiness, or unwanted peaks in the frequency response.

The spikes in the bottom of the subwoofer are standard issue on audiophile speakers (and most DIY jobs). They are said to "limit floor coupling." That is, have the least amount of contact with the floor as possible so that the floor doesn't pick up bass frequencies and resonate with the drivers.

I personally think the paint job is pretty cool, by the way. Certainly not a color scheme that will please all tastes, though.

By: creekree

creekree — Tue, 23 Jan 2007 15:49:31 +0000

nice!
although i would have preferred it if they had left the speakers looking like concrete… i mean, its all a matter of taste, but this paintjob is … kinda awful.

By: Richard

Richard — Tue, 23 Jan 2007 15:14:01 +0000

@crash:

Yes the wax was melted off in an oven.

By: MRE

MRE — Tue, 23 Jan 2007 15:06:47 +0000

all diy projects require spikes! ;)

By: Chuck_Notorious

Chuck_Notorious — Tue, 23 Jan 2007 14:40:26 +0000

Here in Canberra, there used to be somebody who was into making concrete speakers (I guess in the 80s). They would be spheres spun on a potter’s wheel. My dad used to have some but he sold them when I was little (unlucky for me…), a friend of mine has some as well as a classical record shop and I’ve seen one other pair.

They all sound amazing.

By: Crash

Crash — Tue, 23 Jan 2007 10:27:44 +0000

Translation:
http://64.233.179.104/translate_c?hl=en&ie=UTF-8&oe=UTF-8&langpair=de%7Cen&u=http://propirate.net/betonboxen/&prev=/language_tools

So did they just melt the wax out?

By: bjs

bjs — Tue, 23 Jan 2007 04:44:31 +0000

I think the spikes are to prevent the sub from reverberating/vibrating through the floor.