You guys are all GOOFS !!!! Everyone knows that sand will add "grain" and "grit" to a system. It can also sound very "dry" and "bleached".
Your best bet is to use clay straight from the banks of the Mississippi. The soundstage will fill in with far greater "density" while also being "wetter" with increased "liquidity". The sound will be so "moldable" that you will think that the performers are present in the room.
The increased cohesiveness may be due to the fact that the clay will act as one supporting structure rather than the sand acting as individual grains, all with different ideas and motives.
Some folks claim to have had good luck with "moon rocks", but i don't believe them for several reasons : ) Sean
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