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Humidity Control
By Bruce Clark

In response to Ed Gloeggler's request on piano and Violano humidity
control in regard to tuning etc.

Ed tells us that his Violano drops and raises in pitch more or less
evenly according to humidity changes.  The problem is quite normal, but
few persons notice it.

Other than a few select piano owners and tuners, few have any idea of
what you are talking about.  For those who are aware of the problem it
seems to have no absolute remedy, other than placing the instrument in a
climate controlled environment.  Unfortunately most of us cannot afford
this luxury.

Here in the heart of New York State, summers are extremely humid.
Winters are cold and inside air is as dry as the Sahara desert!

In regard to tuning your instrument, you say it raises and lowers itself
quite evenly.  I think I would let it drift.  I say that because if you
raise it when it is dry, when the humidity raises it would raise itself
even higher.  Possibly too high.  Then you have to lower it.  It is
easier to tune the four strings of the violin to the piano, than change
the entire instrument.  Should you feel the need to tune the piano,
figure out about where it has settled, and tune it at that level.  It
will hold it's tune much better that way.

I tune my piano A=440 once a year, the same time of year before the
holidays, it can get pretty bad during the humid summers, but I am
outside and do not play it as much.  By leaving it alone, it will move
itself back and does not require a drastic tuning change before the next
holiday season.  Drastic changes in tuning do not hold up well.  Tuning
twice a year in climates with drastic humidity changes seem to make
matters worse.  A tuner has to undo what he has done.  By leaving it
alone and seeking a happy medium is about the best advice I can give.

I have seen Violano plates crack.  The Violano in question was one in
which a fellow placed a 100 watt bulb, to keep it dry inside.  The
outside of the Violano was very cold and damp.  We were not sure that was
the cause, but it could have been.

For a time, I thought using a de-humidifier in summer and a humidifier in
winter.  That certainly would solve the problem nicely.  My goal was to
keep the indoor humidity at 40%.  I was wrong.

The results were worse than I could have imagined!  During the humid
summer weather, the dehumidifier ran day and night, and removed about 13
quarts of water per day out of my living room air, making little change.
The humidity remained about 90%.  The only thing the de-humidifier did
was make the room hotter and considerably increase the electric bill.
Constant air conditioning during humid weather would help, but it also
can be expensive to operate.  Unfortunately, friends and family could not
grasp the idea of removing humidity, and persisted in propping doors
open to let in the nice fresh (humid) air.  Rather than risk a severe
battle with them, I abandoned the idea of a dehumidifier.

Next, I thought of using a humidifier during the dry winter months, and
keep the humidity up to about 40% That would be a good help.  The
humidifier used about 5 gallons of water a day while keeping the humidity
up.  WRONG again!  You don't do that in old drafty houses in winter!  The
paint on the exterior of my house peeled off!  Moisture invaded the sheet
rock of the upper rooms and the ceiling came down in the upper hall!  The
humidity was fine, the piano loved it!

There seems to be no concrete answer.  Deluxe and expensive Piano
Humidity control units actually can send out steam under dry conditions
and the danger of rust could occur.  During humid conditions, the
steamers are supposed to shut off and the heat rods are supposed to turn
on automatically.  The owners forget to refill them and they not only go
dry but start the opposite effect.  In this climate I do not see that
they make much difference.  I would not want one attached to my piano.
(There is no room for it anyway.) I am also a firm believer that one does
not add heat or humidity to one side of wood without duplicating the
conditions on the opposite side.  We have all seen table tops that have
warped and curled after having a wet surface.  If both sides had the same
moisture content, that would not occur.  The same applies to pianos.

Here is what I have done to help some of the humidity problems regarding
my piano.

I have made cloth wicks and placed them in water filled plastic pop
bottles.  I placed several in the bottom of the piano, and several behind
the piano between the supports.  Over this I have taped a thin sheet of
plastic to keep the humidity somewhat confined, and I also keep the piano
closed up at times when it is not in use.  Most of the bottles of water
require refilling every two weeks during the heating season.  It is a
help, but not a cure.

When the high humidity season approaches, I remove the water bottles, and
replace them with a 30 watt heating rod in the bottom of the piano, and a
30 watt one behind the plastic sheeting on the back.  This seems to help
to some extent.

I have addressed the problem with those who sell climate controls for
pianos, but I do not buy their marketing strategy.  They told me that I
should have one hundred watts of heat rods behind the piano in humid
weather to do any good.  (That's a lot of heat!) Is that supposed to
absorb moisture right through the sound board?  I don't think so.  They
also suggested that I place one of their large humidifiers in the bottom
of my piano.  No room, I tell them.  They then suggest that I place one
behind the piano.  Is the steam supposed to penetrate the wood to the
inside of the piano? Perhaps, (when the steam loosens the sound board!)
No thank you!

Now, if we think of the past, our old pianos have made through the years.
In the old days, there were no elaborate forms of humidification or heat
rods.  The pianos survived.

The majority of piano owners are tone deaf, and have no idea if their
pianos are in or out of tune!  It is most difficult to get it through
their heads when, and when not, to use the heat rods.  In most cases they
leave them on year round or use them at the wrong time of the year doing
more damage than good!  I was a tuner for over 40 years -- I know!

Some of us, like Ed and myself, are sensitive to pitch variance caused by
drastic changes in humidity.  For the time being we can only do our
best to keep the drastic changes modified somewhat, and strike a happy
medium.

I do not think drastic measures of steaming our pianos when humidity is
low, or toasting them when the humidity is high, is beneficial to our
beloved instruments.

I would enjoy hearing from others regarding this problem.

Bruce Clark¶
bac4@juno.com

(Message sent Tue, 04 Feb 1997 14:21:14 EST , from time zone -0500.)

Key Words in Subject:  Control, Humidity