Knabe Tuning Mystery

[William R. Monroe]

Tom,

Right, sharp, I knew that.  At any rate, I frequently see this kind of
movement here in WI when tuning a piano in summer that was seen last in
winter (extreme low RH to extreme high RH).  I'd really have to think that
uncontrolled humidity is the major factor.  Solve that problem, see what
remains and tackle that.  Uncontrolled humidity just seems to make all the
other problems so difficult to isolate, if not pointless to fix.

Still can't really figure the different reactions of the two instruments
(assuming no structural issues) other than to say different animals.

Respectfully,
William R. Monroe


----- Original Message ----- 
From: "Thomas Cole" <tcole@cruzio.com>
To: "Pianotech" <pianotech@ptg.org>
Sent: Tuesday, January 03, 2006 8:49 PM
Subject: Re: Knabe Tuning Mystery


> William,
>
> Yes, these two pianos are definitely at the extreme ends of the humidity
> reactivity spectrum.
>
> Tuning pins are very tight in the block; I wouldn't use 3/0 pins without
> reaming first. But loose pins wouldn't make the pitch go sharp like
> that, so I will be checking block to plate fit and plate bolt tightness
> as others have mentioned. Since the tuning is so reactive, I will
> definitely be installing a DC system (which I very seldom do in this
> Pacific Coast town).
>
> I was wondering what could be going on with the soundboard itself that
> would cause the treble to move so much. But I guess that board/plate
> shifting would explain it better.
>
> Good idea about pieces of hardboard for moving the piano out from the
> wall. For a fussy customer, one could put some felt on the bottoms and
> raise the piano with a modified pry bar (Yat Lam Hong idea that Isaac
> had made and Joe Goss sold).
>
> Tom Cole
>
> William R. Monroe wrote:
>
> >Tom,
> >
> >To me the mystery is why the Schimmel seems to be so good.  With that
kind
> >of humidity level, I'd expect any piano to respond similarly.  I'd second
> >David's suggestion for a DC system - invaluable for any piano IMO.  My
line
> >is something like, "if it is worth tuning, it's worth keeping in tune."
> >
> >When it is restrung, you'll be using larger pins anyway, but I'd make
sure
> >to measure the torque on the pins if not sooner, when you remove them.
> >Check the archive for info on using larger pins and restringing as far as
> >prep of the block goes.
> >
> >I like to carry four pieces of 1' x 3' hardboard in the car.  Lift the
piano
> >and place each under a caster, aimed in the direction you wish to travel.
> >Sometimes they will need to be moved, but are easily spun around again to
> >face the direction of travel.
> >
> >Respectfully,
> >William R. Monroe
> >
> >
> >----- Original Message ----- 
> >From: "Thomas Cole" <tcole@cruzio.com>
> >To: "Pianotech" <pianotech@ptg.org>
> >Sent: Monday, January 02, 2006 11:58 PM
> >Subject: Knabe Tuning Mystery
> >
> >
> >
> >
> >>The piano is an 1895 Knabe, art case upright in exceptional but original
> >>condition. The problem is tuning instability. I tuned it one year ago
> >>along with a Schimmel grand in the same room. The Schimmel sounded
> >>beautiful today, so much so that I declined to tune it. But the Knabe
> >>has become unplayable and out of tune in way I've never seen before.
> >>
> >>Because of heavy rains, the humidity is higher than when I last tuned
> >>the Knabe (72%). I noticed the tenor strings were a little sharp,
> >>getting sharper at the tenor/treble break. Then the treble started out
> >>+25 cents and the top few notes were at or near +50 cents. Bass was
> >>slightly sharp.
> >>
> >>The owner says that the Knabe tuning never lasts more than two or three
> >>weeks. He plays it much more than the grand, so this is a factor, but he
> >>is not a heavy player. The owner wants to restring, because strings are
> >>starting to break, but not change the soundboard. The board, bridges and
> >>pins look like new, but I was not able to check crown (owner afraid of
> >>hardwood floor damage if I move it).
> >>
> >>How can I find out what is causing this tuning instability? Why would
> >>the tuning go so sharp in the treble, as opposed to the tenor where you
> >>would expect? Can anything be done in the course of a restringing to
> >>improve stability?
> >>
> >>Tom Cole
> >>on the Left Coast
> >>
> >>_______________________________________________
> >>pianotech list info: https://www.moypiano.com/resources/#archives
> >>
> >>
> >>
> >>
> >
> >
> >_______________________________________________
> >pianotech list info: https://www.moypiano.com/resources/#archives
> >
> >
> >
> >
>