All,

I did not use reinforcing in the base of my instrument, and I did use a=20
sand mix of concrete. I also let it sit in the mould for a week, and it was=
=20
well over a month before the instrument was complete. I cannot say that I=20
have seen any noise that I can attribute to the use of this construction=20
technique. For the record, my base is about three feet long, 8 inches wide,=
=20
and about 6 inches high. It is shaped like a "U" in cross section to reduce=
=20
weight, and to minimize the cross section thickness. The column is also=20
similarly shaped with  the back side hollowed out. The two pieces together=
=20
weight 80 or 90 pounds. It was a real effort to get the assembly off of the=
=20
workbench and down onto the floor.

The instrument lives in a temperature controlled enclosure at about =B10.5=
=B0F.=20
I consider this necessary to avoid thermal effects particularly because the=
=20
thing is set up in a corner of my garage which, although attached to the=20
house, is not heated.

Dave...

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