rib placement

[Delwin D Fandrich]

Ron Nossaman wrote:

> Hi all,
>
> I have a question that's probably in Del's area of expertise more than the
> rest of us, so I'll address it mostly to him.
>
> Del, I think you said in a post a while back that the tone quality in the
> problematic high tenor/low treble, octave 5 1/2 - 6 range, could be
> significantly improved by changing the ribbing arrangement in that area. Is
> that correct? If so, I'm curious how the crown in the redesigned area holds
> up with time. This section always seems to have the worst time maintaining
> crown through the years and I was wondering if you have had a significant
> number of custom ribbed boards out there long enough to get a good cross
> section on their aging characteristics. Does your modification involve
> height contour changes to the rim? Why does this section of the board tend
> to go flat in the first place? I hope this is a fairly simple thing, and I
> haven't started one of those "neverendingthreads"?
>
> Thanks,
>
>  Ron Nossaman

----------

Ah, yes. The "killer octave." The earliest experiments I conducted along these lines were done about
six or seven years ago. I didn't really refine the techniques until just a year or two ago. And
since there is at least one -- possibly two -- patent application involved, I don't want to go into
any detail as to exactly what I'm now doing. However, there is nothing being done that would hurt
longevity of either the soundboard itself or soundboard crown, and much is done that should help. As
far as I know the pianos have retained their voice quite well.

While you are correct about the problem of premature lost crown in this area, this loss is not
itself the main problem. New pianos with adequate crown still have tonal problems in this area.
Witness the heroic efforts made by factory technicians to voice them evenly. Incredible amounts of
hammer shaping and hardening goes on to overcome the problems in this area.

It is truly a joy to be able to treat this area somewhat more gently. We don't commonly use Steinway
hammers, but on the last couple of sets that we have used we find ourselves needling them down
through the entire upper tenor and treble sections. In several cases, all the way through C-88. It
is rare to use any hardening solution anywhere in the scale and, aside from a light sanding to clean
up the surface, we do no serious hammer shaping. And still we have had comments about how "bright"
the treble sections are. So, it can be done.

There is a series of articles coming up in the Journal -- starting in December -- that deals with
soundboard crown and the various maladies that develop in soundboards that I hope will answer at
least some of your questions. It is a complex subject and I'd prefer to not go into all that detail
here.

Regards,

-- ddf