Q&A: Is concrete bad for speaker stands ?
Well, Yes and No. Sometimes.
It is not bad for speaker stands, provided that you use it together with other materials.
An important “other” material is … sand.
Sand, as a filling material, in some sort of tube or enclosure.
Why is this important ?
Sand has this natural tendency to come in small grains. Grains that fairly easily move and rub against each other. The consequence of this fact is that any and all, even the smallest possible micro-vibration, such as the vibration of the walls of the tube or other structure that the sand is filling is instantaneously converted into micro-movements of the sand.
This in turn results in micro-rubbing of the individual grains of sand against each other.
This in turn results in micro-heating up of those particles. As any and all friction produces heat.
So, to make a long story short:
“Bad” vibrations are eliminated, by means of converting them into “insignificant” … heat.
Simply put: the conversion of one form of energy into another.
That is the reason why the stem of those speaker stands that I presented, is actually a piece of pipe, filled up with sand. This is not a coincidence.
But anyway, before you even THINK of filling ANYTHING up with sand, be sure to BAKE IT.
In the Kitchen oven, or any other oven. Be sure that it is absolutely dry and void of any slightest trace of moisture.
Once you fill up the cavities of your speaker stand with sand, be sure to seal off the holes, so that the moisture from the surrounding air does not penetrate into the insides of that void and into that sand.
That’s about it.
Concrete + pipe(s) + sand constitute marvelous speaker stands.