Standard Pitch 1870 to Present

[Delwin D Fandrich]

----- Original Message -----
From: "Tom Servinsky" <tompiano@gate.net>
To: <pianotech@ptg.org>
Sent: September 18, 2001 5:47 AM
Subject: Re: Standard Pitch 1870 to Present


> Terry,
> According to Bob Beck, one of the few welders of broken plates in the USA,
> raising pitch beyond the designated A435 could pose problems....broken
> plates. However, as we all know many pianos have been brought up to
standard
> pitch and do well with the additional tension.

In most cases the somewhat less than 2.5% added tension will not cause any
problem. Most tuners add more than that routinely as they pitch raise a very
flat piano.



> The unfortunate situation in which I had to talk to him was with a broken
> plate issue on an old Sohmer grand ( 1875). Apparently Sohmer and Weber
both
> used extremely thin plates and were prone to breakage with any additional
> tension.

Sohmers also tend to use extremely high string tensions. The highest tension
scale I have recorded to date was on a Sohmer at around 65,000 lbs (about
29,500 kgf). And, yes, their plates tend to be a bit light. The combination
can be lethal and tells us a lot about just how sturdy these old things
are--they rarely fail.



> Thus A435 for these instruments meant A435.
> He ended up welding the plate but insisted on us rescaling the piano so
that
> it will tolerate A440.  According to him each 1/2 size ( string size)
> represented 1000lb change in tension, thus he was most concerned around
the
> strut areas not to exceed certain limits.

Rarely will a rescaling consist of simply reducing the size of each string
by 1/2 size. Early scales--and most still in current production--are all
over the ballpark. Most rescaling work will add some in some areas
(typically the treble and low tenor) and take some away in others (typically
the mid tenor) and generally even things out (across the whole scale,
including the bass).

Del
Delwin D Fandrich
Piano Designer & Builder
Hoquiam, Washington  USA
E.mail:  pianobuilders@olynet.com
Web Site:  www.pianobuilders.com