String coupling.

[Ron Nossaman]

> I think I can explain this one.  Pitch drop,
>if it exists, would be based on coupling through the bridge.  When the
>unison is tuned with TuneLab, the selected partial is perfectly matched
>across all three strings (even though other partials may not be).  And
>when all three strings push the bridge up and down in unison the bridge
>appears more resiliant (to the selected partial only) and thus the
>effective termination point is moved a little further back and the pitch
>drops (for the selected partial only).  When the interval is tuned
>aurally, you make compromises that are better overall, but perhaps a
>little worse for the one selected partial that TuneLab is using.  So
>at that partial, the three strings are not pushing exactly together
>and the bridge does not appear more resiliant and the pitch drop
>does not happen.  Sound plausible?
>
>-Robert Scott


Hi Robert,
Looks like we're on a similar track. I think it's sounding more plausible
all the time. 

BTW, do you happen to know of a real time spectrum analyzer for Dos/Win
machines in shareware?

Ron N