[pianotech] Inverted soundboard

[Delwin D Fandrich]

As have I. But there is a reasonable explanation for this that has its basis
in the shape, size and type of soundboard system in the killer octave region
of the pianos that develop this anomaly. The problem described in this case
is not common to this piano. At least not so far as I know. Which makes me
wonder just what might have caused the problem. I'd not be surprised to find
in the end it was man-made and not an act of god.

ddf

Delwin D Fandrich
Piano Design & Fabrication
620 South Tower Avenue
Centralia, Washington 98531 USA
del at fandrichpiano.com
ddfandrich at gmail.com
Phone  360.736.7563


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Ron Nossaman
Sent: Tuesday, December 07, 2010 6:07 AM
To: pianotech at ptg.org
Subject: Re: [pianotech] Inverted soundboard

On 12/7/2010 7:53 AM, Terry Farrell wrote:
> Reminds me of my first adventure into piano technology (before I got 
> into the business). My brand new S&S 1098 with a full quarter-inch of 
> reverse crown - stretch a string across the back of the panel parallel 
> to ribs, let string touch panel in center and observe both ends a 
> quarter inch off the panel. I wish I remember whether I had taken any 
> string bearing measurements - however I seriously doubt it - would 
> have been interesting though. Dog-gone hard to imagine exactly what 
> might have caused such a condition.

A couple of accumulated years of comparing crown and bearing measurements
turns up a surprising number of killer octaves with both reverse crown, and
negative bearing.
Ron N