voicing

[Ron Nossaman]

>I don't disagree, but since the board/ bridge design is fixed, I can only
>work with what I can vary.

* No argument there. In field work, so do I (unfortunately).

>How ever due to the audible lenght of the partial string, and given that
>hammers do not often wear evenly, and phasing due to hammer angles being
>critical, this area will always  have a certain amount of unevenness within
>the assembly process.

* Audible length of the partial string? 
* Hammers won't wear evenly with any kind of design or construction will
they? How about the horrible voicing problems in new pianos?
* Aren't hammers drilled at an angle somewhere as close to being parallel
with the string as is practical and still clear the adjacent hammer without
leaving a razor edge on the side of the molding when the tails are shaped? I
don't recall ever seeing a set where the drilling angles matched the string
angles through the whole scale, but I have seen them where the angles didn't
match anywhere. Now I've been known to not pay attention and fail to notice
things, sometimes for years and years, but I haven't observed what I would
call a phasing problem caused by hammer angles. I'm apparently missing
something. Do you mean the same sort of sounds as from a unison where the
strings aren't mated to the hammer strike point? What are the critical points?



>The change of string type will also be a factor, since you are introducing
>an extra vibrating mode from the winding.

* Otherwise known as scaling, which is to a great degree predictable and
controllable. When the scale was well designed, the voicing problems are
minimal. Sadly, that isn't always the case. Also, the sound of wound strings
seems to change more with age than plain strings and requires some voicing
touch up and blending across the break. I've strung pianos where I couldn't
detect the transition between plain and wound strings on the tenor bridge
from sound alone. That was after leveling, and before any hammer voicing was
done. Before I did any rescaling, this didn't happen much. If you measure
the scale of a problem piano and plug the numbers into a scaling program or
spreadsheet, you can see on the graph where the problems are and they nicely
coincide with what you hear in the piano.

>Board design will not completely correct these variables only minimize them.

* Nothing is 100%, but it's sure nice when the designers and manufacturers
can get somewhere close before the piano ends up in someone's living room
with a big voicing problem. It's easy to keep a well designed piano voiced.


>Since string winding tension ect has a large effect on the harmonic content
>and power, please educate me on how you integrate the bass string
>scaling/design with the Z of the board.
>A direct formula will suffice. 
>Regards Roger

* Again, that's scaling, and is graphable and reasonably predictable in the
design stage. As for the soundboard, I agree. A direct formula would
certainly suffice. Harold Conklin published what he called a characteristic
impedance formula for strings in "Thoughts on Thoughts" in the Journal that
is quite helpful in scaling. Technicians have always believed in hammers.
They have partially accepted, and are beginning to believe in string
scaling. They don't yet believe in soundboards, but when the right people
with the necessary mathematical knowhow start believing in soundboards
enough to actually explore the possibilities, we'll eventually be able to
graph that on the spreadsheet too. Until then, I have to go on the basic
concepts of impedance, as introduced by Del, and discussed at great length
on the list, and personally observed cause and effect relationships. Kind of
like voicing.

 Ron N