Impedance matching

[Richard Moody]

----------
> From: Jim Coleman, Sr. <pianotoo@imap2.asu.edu>
> To: pianotech@ptg.org
> Subject: Impedance matching
> Date: Tuesday, December 29, 1998 10:52 PM
> 
> Hi to all interested:
> 
> I picked up this idea from Dr. Kent when Chuck Walter and I were working

> under him at the Conn Co. Our first piano design was for a 36" spinet
where
> we deliberately used a reverse crown but had plenty of downbearing. This
> certainly eliminated the possibility of the soundboard developing the
> oilcan effect. . They only vary primarily in the sculpturing processes
and
> in the rib loading.
> 
> Jim Coleman, Sr.

Hi Jim. 
	Did the spinet sb have a reverse crown before it was installed, or result
from down bearing on a flat board?  Do you have any figures on the curve? 
Any diff from a positive crown contour?   
Richard Moody