Pitch Floating (off on a tangent)

[Ron Overs]

List, 

Avery Todd wrote;

(referring to a S&S Ds under his care)
> Almost invariably, the low tenor is sharper than the rest, with it
>basically decreasing as one goes up the scale, at least after the lowest
>treble break. Then the bass is almost always right on.

This tendency is typical, since the percentage of breaking strain is 
lower here than for other areas of the scale. Further, down bearing 
settings, which tend to sink out less at the bridge end points, can 
compound the problem. The actual (at pitch) down bearing angle can be 
excessive at the bridge ends.  I believe the bridge ends should be setup 
with slightly less down bearing angle than for the centre of the bridge 
sections, which will tend to sink out more when strung.

Steinway Ds are not alone in sharing the symptoms Avery describes. Yamaha 
CFs, Kawai EXs and others,  also share the speaking length of the S&S D 
at note F21, ie. 183 cm. Why? I can't believe that this length is the 
answer to 'life the universe and everything'.

Pianos such as the U1H Yamaha, scaled (on the long bridge) with two wound 
bichords adjacent to the bass/treble break, are even more of a problem. 
The last plain  wire (F33) has a tension of only 65 Kg, while the bichord 
on note E32 is strung at  92 Kg. (A 35% change of breaking strain 
tension). This type of scaling regime (used by so many manufacturers) 
results in pianos which exhibit inferior tuning stability, while at the 
same time the tuner is left with the impossible task of blending the 
tenths and seventeenths with the fourths and fifths. Nothing fits as it 
should!

Why do piano designers keep producing pianos with such inappropriate 
scales? Why should tuners have to battle with pianos which have such poor 
scale design? There are scaling answers to these problems. Why don't we 
identify them? Perhaps factory techs and designers might well benefit 
from a stint  out on the road to experience some of the problems they 
inadvertently subject us to.

Some of Carl Ronisch's scale designs (at the turn of the century) were 
way ahead of his time, while many popular modern designs appear to 
represent a considerable step backwards.

Ron E. Overs
Sydney, Australia

Email: ron@overspianos.com.au
Website: www.overspianos.com.au