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
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.
I used small round pebbles, available at Home Depot in 50lb. bags. Be sure they are dry before using. They are a lot less messy than shot or sand. Filled stands will not effect the position of the stands and I fill them up all the way as long as the stands don't exceed 24" or so.
The speaker stands I just got are filled with a limestone acrylic polymer injection to deaden the sound yet when I strike the metal, I get a single pitched ring no matter where I strike it. It's short in duration but I'm going to get some CLD Tiles and cut a narrow strip to attach to the inside of the upper brace to further deaden things.

It won't be visible with the speaker on the stand so that should be all that needs to be done.

All the best,
Nonoise