Filling speaker Stands?


I have a modest system. Continually look for ways to improve it's performance even to a slight degree. I have read many posts about improvements than can be achieved by filling the hollow spaces of some speaker stands with some type of material....sand, kitty litter, lead shot, and some others. Here are the stands I have......
https://www.sanus.com/en_US/products/speaker-stands/sf26/ 
These stands are of metal construction. There are 2 upright support tubes which are approx. 2" diameter. The stands sit on a carpet floor with spikes. On the top plates are a layer of Sorbothane and PSB Imagine B speakers sit on top of that. The 2 metal supports are attached to the base and top plate with just threaded holes about 1/4 " diameter. Pouring some type of dampening  material would definitely require a funnel.
The reason I ask this question is that, when I thump on each upright post, it rings for several seconds. A dampening fill would minimize this but would filling those posts really benefit the speaker performance to even a small degree given my modest setup? I don't know. Probably, few have experimented with this type of scenario.Thanks for any advice.



jrpnde
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I filled my racks (made of hollow square tubing) with dried sand.The main reason to not use lead is the years from now disposal. No one will know they are filled with lead. (unless they know from lifting them?) but the disposal may be problematic. Also pets. Say you spill some and a pet or visiting toddler eats it two month later?So I say skip the lead. I am very happy with the sand. And I had only a few small holes.. What I did was make a funnel out of clay! Stuck it right ON the metal tube, worked perfect. Sealed the holes later with silicone ealant.
Do not use kitty litter unless you are in a very dry climate. It absorbs moisture, will expand and be hard to remove. Go to Home Depot and get a 40lb. bag of small pebbles, make sure they are totally dry before pouring them in the stands. They are easy to pour in, shake the stands to pack them in tight, easy to remove and dispose of if need be.
Sand is the easiest to get through small openings. It is heavy and inert. Lead? Don’t bother. You are looking for speaker stands that don’t resonate, not speaker stands that The Hulk couldn’t pick up.