Filling speaker stands: sand, lead, steel, rice. Full, half, etc?


With my proac tablettes, I am using 28 inch speaker stands which have two round steel tubes about two inches in diameter.  The stands have spikes into my wooden floor (through carpet) and rubber pads on top.  I have a rather small room 12x12, and I have played around with the speaker positions in the room, finding a pretty sweet spot optimizing the bass and soundstage.  I have done all this with the stands unfilled.

so I am looking for advice on filling the stands. What do I use: sand, steel shot, lead shot, rice?  Do I fill them half full, three quarters, or full? Do I fill all the tubes the same? Can overfill makes things worse?

like most things (i.e. speaker placement) I suspect there will be some trial and error, but as it will be a real pain in the rear to fill/empty/refill the various materials to really compare, I am hoping that there are some lessons learned that the rest of you can share with me to get me pretty close with my first trial.

Alos, what effect will the filling have- should I expect deeper bass, bigger soundstage, greater depth, more detail, or..... better yet what should I not expect to change? This will help me know what I should be listening for as I tweak things.

and finally, should I expect my current optimum speaker position to change with filled stands? Will I have to go through the whole positioning exercise again?

thanks, ( and happy new year)

Bill
meiatflask
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the idea is to make the stands as heavy as possible so that speaker cabinet movement (caused by the bass reflecting off the cabinet walls) does not modulate the sound

sand will leave less of an air space than lead shot (so the stands will be heavier than you might think) and is not toxic

cones might help too

I bet Dick Vandersteen has a white paper on this...
On the sand being dry- I wonder if an arts and craft store like Michaels or similar would have a dry sand.   I could see that if wet, sand could grow things and smell.

I appreciate the comments about lead safety, but am not worried.  As a metallurgical engineer, I know my way around these things. 
For dry sand, look for Silica at a building supply yard near you. It is not organic sand, but rather man-made, and is used in sand blasting. It is available in many different grades---the size of each grain---60 being a good one. A 100 lb. bag cost me less than $10.
I bought several bags of lead shot and was very unhappy with the experience of filling a pair of stands with them.  the dust got all over my hands and arms, and filled the air i was (trying not to) breathe in
during the 30 minute process as well.  My brain cells are already grown and are a done deal, but lead is lead nonetheless.  The stands were heavy as hell afterwards, but i hope that ultra-fine dust
doesn't find its way out of a crevice somewhere on the stands. The vendor did not exactly describe the dust problem on their web site either, so beware of what you buy and how it's supplied.  And lastly,
don't expect to EVER try to reverse the process without a special mask on, double gloves, and a long-sleeved disposable gown.