RC vs CC again (was Re: compression ridges)

[Robin Hufford]

Hello Cy,
     I agree, as I said, with Ron O's comments about loading, generally,
being at its highest in this area and this region is more susceptible to
changes in crown and downbearing as a result of this loading and this is the
mechanism by which this area may, occasionally exhibit problems even though I
believe here on the list generally commentary is too severe in this regard.
Some contributors to this list assert that there is, in addition, a weakness
in the belly rail which I, myself, am rather skeptical of as a significant
factor but would not completely discount.
       In my opinion, for what it is worth and I don't wish to be taken as
any kind of expert in this area or any other which I make comment on,  but
rather as someone merely recounting experiences and observations,  these
changes in conjunction with changes produced by wear and time  in the action
not to mention massive, major departures from original design
characteristics, collectively may create a somewhat drier, harsher sound
which can, in my experience, be overcome by reestablishing the original
mechanical characteristics in the action,  even though the crown in this area
may be absent or substantially lessened.  Of absolute preeminence in this
process is the design and nature of the hammer and entire hammer assembly -
meaning an overcentering, very light  hammer and light,  flexing shank.
      It is important for the hammer to accomplish its impacts on the string
and be gone as soon as it can as this will lessen its interference with the
traveling wave returning from the Capo.  Even though the distance to the
termination is much closer higher up the scale, it is sufficiently close such
that, in connection with the increasing size of the hammers dictated by the
overall increasing size and length of the string the hammer/string contact
time becomes long enough to create interference by the hammer with the
traveling wave.  Such interference which, I believe, happens in almost all
pianos to some degree or another in this area, degrades the formation of the
standing waves which load the soundboard one way or another.   Steinway's
designs in from about 1885 keep this to a minimum in the most efficient way
possible, in my opinion.  Also, again only one man's opinion, this is the
most efficient possible use of a hammer assembly, and, I think, the more
conventional 90 degree installation is substantially less efficient.
     The point, though, that I tried to make, is that I can't agree that the
numerous tonebuilding and strungback repair techniques available to
technicians cannot correct this problem where there is one.  They can.
     Any set of hammers that has to be lacquered any more than in the last
octave or so, is intrinsically a defective set, in my opinion and I place
little store in the techniques of "voicing up" or "down " even though I have
learned them myself at a prominent  factory or in seminars here or there
where this whole process has been elevated into a kind of professional art
and skill which I think is complete nonsense technically and, fundamentally,
a fraud.    This entire process, coupled with the vastly larger heavier
hammer frequently found on new American pianos,and the large, monstrous
shanks lets this area stand out first as slightly different on some new
pianos in some cases.  But, it is a big mistake, in my opinion, to jump on
this and immediately conclude the soundboard has failed which is a most
common assumption made here.
     Having said all of this, nevertheless, one seldom finds customers, as I
said in the post the other day, complaining of such things on new pianos.
     Also, the big gorilla factory puts out these pianos with the limiting
approaches indicated above:  As technicians we have to live with what they
dictate where problems are noted, usually in an academic or concert setting.
To some degree or another and this requires, short of major rebuilding,
adapting to their procedures even where they are technically inadequate, at
least to my mind and this is one of the reasons I now try to keep my distance
from them.
     Older pianos arrive, if they do which I think from my experience is
exaggerated,  at problems in this area through a different route but the
solution is the same.  I firmly believe it is not necessary to install a new
board to correct such things even if the crown has all but disappeared in
this area, although one may wish to do so for other perfectly valid reasons.
Regards, Robin Hufford

Cy Shuster wrote:

> Robin,
>
> Just trying to understand here -- are you saying that "killer octave"
> problems can be caused by action problems as well as soundboard
> characteristics?  Is there a mechanism by which octaves 5 or 6 would have
> more action problems than other octaves?  (More wear from play, perhaps?)
>
> --Cy Shuster--
> Rochester, MN
>
> ----- Original Message -----
> From: "Robin Hufford" <hufford1@airmail.net>
> To: "Pianotech" <pianotech@ptg.org>
> Sent: Monday, September 29, 2003 3:02 AM
> Subject: Re: RC vs CC again (was Re: compression ridges)
>
> >      In my opinion, the so-called killer octave is exaggerated as a
> > generalized fault of most of these instruments when brought up here on
> > the list and there is a particular reason for this.
>
>   <snip>
>
> >       I believe an analysis of this expressed years ago in the Journal
> > of problems here being a function of the hammer line and elastic
> > characteristics of the hammer assembly ( this is also a large subject),
> > and striking point versus traveling wave speed on the string,  is at
> > least as important as is  it being considered a function of soundboard
> > characteristics and a measure of board failure.  There are a large
> > number of factors that, when optimal,  avoid loss in energy delivery
> > ultimately to the board, as, of course, you know, and which contribute
> > to the sound produced.  Collectively, they are absolutely critical.
> > For example, tight bridge pins, hammer centers, jack centers, string
> > levelling, hammer angle, terminations efficiency,  and others all of
> > which are frequently examined here.
>
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