Bridge as a 2nd class lever

[Ric Brekne]

Hi list

Those of you who were at Rochester and attended Ron N's class might 
remember he spent a bit of time talking about bridge leverage and had 
some printouts of the results of a mathmatical model he and Phil Ford (I 
believe) worked out. If anyone has copies of these printouts and could 
get them to me I would be very greatfull.

As I understood this, any increase in downward pressure on just about 
any place on the long bridge also exerted some significant pressure on 
the area roughly equivalant to the killer octave.

I've been trying to see if there should be any consequences for tuning. 
One would think that if the model is correct, then any significant 
change in string tension over a large region other then this killer 
octave area would result in a predictable change in string tension there 
as well. This because string tension directly affects how strong the 
downbearing on the bridge is.  I've been looking at this for several 
days now and today I lowered tension on a Bechstein E that I had tuned 
to 442 the other day.  I lowered the tension from C5 to A0 and then 
measured C5 upwards. With the lesser tension from A0 to C5 I would have 
expected an area above C5 to rise slightly in pitch if the model was 
correct. No change at all in this test, at least nothing I could measure 
with Tunelab useing two and a half hours to do the deed. 

I'd like a much closer gander at the printouts and the assumptions 
made.  As far as I understand there has been no attempt (outside of mine 
today) to actually measure in any way whether the model holds true ??  
If someone knows otherwise please send along whatever info you have.

Thanks for any and all comments
Cheers
RicB