Oops... Re: Unusual rib structure?

[Delwin D Fandrich]

----- Original Message -----
From: "gordon stelter" <lclgcnp@yahoo.com>
To: "Pianotech" <pianotech@ptg.org>
Sent: May 07, 2003 6:43 PM
Subject: Re: Oops... Re: Unusual rib structure?


>      But, from the photos, this does not look like the
> builders' intent in this case, to me.  Looks to me
> more like they were just trying to get more vibration
> spread around into the dead corner. Not define it from
> the vibratory portion with a vibratory stop.
>      Sort of a different idea, it seems to me.
>      Respectfully,
>      Thump


Yes, it is different. These things are not cutoff bars. But they do act to
stiffen the structure. And in doing so they make the soundboard assembly
somewhat stiffer through that region and that stiffness raises the
impedance slightly. That is one part of the function of a cutoff bar. A
small part, to be sure, but still a part. It works considerably better, of
course, to put in a proper cutoff. But, if you've painted yourself into a
marketing corner and find that somewhat awkward, well....

The idea is to keep the available energy out of that corner.

Del