[pianotech] GH-1s

[Jim Ialeggio]

David L wrote:

<So, I guess I'm not sure what you mean by "this disconnect continues to 
this day, to define and unfairly limit small belly design, and, mind 
bogglingly, define upright design as well".

My comments mostly have to do with wrapped strings, as the small piano 
"problem" becomes problematic in the transitions and low tenor through 
the bass. The square acreage of the small soundboard limits the 
amplitude of that belly. Trying to drive that amplitude when it is not 
there to be had is to my thinking a problem. So, my take is that since 
the board simply cannot physically comply with amplitude requirements to 
the degree a large belly can, the strings in a small belly are asked to 
make up the difference by making a more complex, noisy, and thus loud 
sound.

At least according to my messing with the spread sheets, the lower end 
of a workable low tension scale in the bass, using modern wire, is or 
has been defined by the need to effect a smooth transition into the 
plain wire. Smooth in terms of loudness, as well as other string scaling 
parameters. Since the in the plain wires low tension trebles are about 
160lb/string (480lbs/ plain wire unison) the effective bottom end of a 
modern low tension bass scale ends up being around 190/unison to approx 
300lbs or so at the mono to bichord transition, and then the transition 
from 300 to 480 by the trichord transition.

If you were to try and drop the bottom end of the tensions in the 
bass/low tenor curve,  in order to create a quieter bass sound, with 
less noise, a sound which makes up for lack of amplitude with stronger 
but still relatively soft presence of real low partials (fundamental 
still remains mostly absent because of belly size limitations), the 
transitions both from tenor to plain becomes problematic in terms of BP% 
and loudness. The differential in loudness between wraps and plains 
becomes problematic as well.

So in this case, where the lower end of the wrapped string tensions are 
determined by needs higher in the scale at the wrap/plain transition,  
the material itself, ie the tensile strength of the wire, becomes in and 
of itself the decision making entity, as the BP%  cannot be 
appropriately messed with. In this case a key aesthetic decision is 
being made not by me, but by the steel available to me.

My experiments with dropped tensions and lower tensile strength wire in 
the bass on small pianos have been encouraging, and I am continuing 
them. But it does mean having the freedom to explore sounds other than 
the bass growl, which in a small belly, to me sounds more like a 
caricature than the growl of a lion.

At least that's my take.

Jim Ialeggio




-- 
Jim Ialeggio	
jim at grandpianosolutions.com
978 425-9026
Shirley Center, MA