Key MOI and FW data

[Mark Davidson]

Ricb wrote:

>Nice stuff Mark. I would think a few hundred such samples
>would be a good basis for a real meaningful data base
>from which to start drawing conclusions.

Isn't that about the number of pianos you have there at the conservatory?
Or maybe we could do something like a "Piano key inertia road show" where
people bring their old pianos in and we measure their key MOIs.

>How do you explain the FW's being higher values then
>MOI in the bass, and then lower for the rest of the piano ?

Not sure there's any real relationship like that.  Measuring different
things, different units, etc.  I just put them on the same graph because it
helps to see that yes, the big dips and bumps do come at the same places.
Also remember that an unleaded key is almost balanced - the FW results
mostly from lead, while only about 30-40% of the key inertia in the bass is
due to lead, so these curves will look a bit different.  Key inertia will
never go much below 20 kg cm^2. (Different slopes and Y-intercepts, your
math teacher would say)

-Mark