What about purchasing a Used Yamaha Piano?
Customers frequently call Yamaha Piano Service to ask about a used
Yamaha piano. Typically, they want to know how old the piano is, whether
it is a good piano or not, how much the piano is worth and if they
should purchase it or not. We do our best to answer their questions,
from a technical standpoint. We first remind the customer that they
are asking us about a used piano. We explain that there is always
some degree of risk involved in purchasing any used product. Without
a thorough inspection by a qualified technician, it is impossible
to know whether the piano has been properly maintained, or is damaged,
how worn out it is, or if it's in need of major rebuilding. Most times
however, the used pianos the customers are asking about were not originally
sold in the USA. This adds a whole extra dimension to the risks involved.
problem with Used Yamaha Pianos made for the Japanese market?
Yamaha has been making pianos for over 100 years. They had been
manufacturing them for Japan and the Asian market for over 50 years
before exporting pianos to North America, Europe and Australia.
In the 1960's, Yamaha began exporting pianos to these new regions.
Yamaha engineers were not aware of the level of dryness that existed
in North American homes. Consequently, some of the Yamaha pianos
sold in North America during the 1960's developed dryness - related
problems. Upon researching these problems, our engineers found that
in general, the indoor environments of homes in North America are
considerably drier than in Japan.
This research led Yamaha to the development of computer-controlled
drying kilns, as well as other manufacturing procedures, so that
pianos destined for dry climates would be properly seasoned for
the homes they would be placed in.
The used pianos being brought to North America today are pianos
that were manufactured for the Japanese market. These instruments
were manufactured using the same seasoning techniques that were
used on the many pianos we had moisture-related problems with. To
make matters worse, these pianos have lived in a very moist environment
since they were new.
So what does
Yamaha Corporation Of America recommend?*
Will one of these pianos develop severe problems after drying out
in your home? Unless the piano is placed in a very humid environment
(similar to Japan), the piano will dry out, and may develop problems
that will be expensive to correct. We know this from the numerous
calls we receive from customers and piano technicians reporting
dryness-related problems with these used pianos brought in from
Japan. We do not experience these types of problems with pianos
that are seasoned for the North American market.
Based on our experience with pianos not seasoned for the North American
market, from a service standpoint, we strongly discourage the purchase
of one of these "made for Japan" pianos.
Yamaha Piano Service Manager, Yamaha Corporation of America
comments while written for the US market, clearly apply equally
for the Australian Piano Market. They give the historical reason
behind Yamaha seasoning pianos specifically for different climates.
It was not just an idea of a good thing to do, it was specifically
to overcome problems they were having because of dryness. This is
why Yamaha is adamant that they need to go to the trouble of seasoning
all timber to the correct moisture content for every piano they
build, and are equally adamant that these pianos should not then
be exported to a country like Australia with a different climate
than the one the pianos were manufactured for.
WATER and WOOD
Extract from a technical discussion concerning the effect of
humidity fluctuations on the piano - by Leroy Edwards - Piano Technician
point, often misunderstood or ignored when working with wood, is
that the physical size of a piece of wood is affected by it's moisture
content. Not only affected, but greatly affected. This is what causes
furniture drawers to stick or rattle and soundboards to crack or
lose tone. The facts and figures that follow are taken from the
book "The behaviour of Wood" by R.Bruce Hoadly.
A tree contains
water, a lot of water. Once it is felled, it starts losing moisture
to the air. The amount it loses depends on the amount of moisture
in the air. Nature's goal is to have the moisture content of the
log and the air become "equal".
The water in
the log is stored in 2 different ways. One is the water in the cells
and fibre construction itself. This is called "Bound Water".
The other is the water in the cavities between the fibre constructions
and is called " Free Water". A good comparison would be
a sponge. When completely wet it has free water that you can squeeze
out, and after the best job of squeezing has been done, all the
free water is gone. What remains keeping the sponge wet is bound
In most freshly
cut logs, water will account for 70 - 80% of their weight. In the
drying process, losing all the free water (which happens first)
will reduce the water weight to approximately 28%, regardless of
the type of wood. Losing free water does not affect the dimension
of the wood. If a piece of wood at it's fibre saturation point (around
28%) is placed into an oven, virtually all of the bound water can
be removed, and during the oven drying process, the shrinkage of
wood occurs in three different ways. It shrinks less than 1% along
it's length, about 4% across the grain, and 8% with the grain.
When wood is
seasoned to some specific EMC (Equilibrium Moisture Content) and
the parts of a desk, table, piano or whatever are cut to specific
sizes, they remain at those specific sizes only as long as the EMC
of the wood does not change.
and piano makers have found that the environment in North America
and Australia creates a situation that necessitates seasoning of
wood to around 7% or problems will occur. In fact the extremes of
low relative humidity in some homes in Australia can dry the wood
below the 7% figure. 7% EMC is a point around which the EMC in homes
in North America and Australia centres. Some days the wood will
absorb moisture and the EMC raise above 7%, somedays the opposite
happens. Wood has an elasticity function that allows some movement
without cracking, but if the limit is exceeded, damage occurs.
We need to be
aware that the hundreds of moving parts in a piano action are machined
to very exact sizes, (particularly when compared to a drawer in
a Chest of Drawers), and even small changes in sizes can cause problems.
Other parts of the piano, such as the sound board and pin block
can also be affected to varying degree.
REDUCES THE MOISTURE CONTENT OF WOOD
Yamaha seasons timber for piano manufacture, depending on the relative
moisture content in the major cities in the country in which they
will be sold. For Asia to 11% EMC.For Europe 9% EMC. For North America
and Australia 7%.
3.5% CHANGE IN EMC CREATES A 1% PHYSICAL SIZE
DAMAGE CAN OCCUR TO A PIANO BECAUSE OF LOWERING EMC AFTER CONSTRUCTION
If the soundboard becomes smaller, a small amount of shrinkage means
the curvature becomes less (some crown is lost) which causes loss
of tone quality. More shrinkage means greater loss of tone quality.
Still more shrinkage can cause cracks in the soundboard, and buzzes
and vibrations in the sound.
As wood in the action shrinks, the excellence in the touch that
Yamaha is renowned for is lost. The keys don't stop working, but
a prime reason for buying a Yamaha piano is their exceptional "action"
or "feel" and this will be lost.
As wood in the pin block shrinks, the pins can become loose, and
therefore the piano will go out of tune.
As wood in the body shrinks, glue joints become stressed and can
finally fail. Cracks may appear in the basic construction of the
piano - back posts, curved rim, etc. Some back posts may no longer
touch the rim. Polyester finish may crack or lose adhesion to wood
Relative Humidity (RH) is the percentage of water in the air compared
to the maximum it could hold at that temperature. Reports on TV
or newspapers quote outside RH not inside.
To keep wood at 11% EMC it is necessary to keep the room at a
constant 60% RH.
To keep wood at 7% EMC it is necessary to keep the room at a constant
4% EMC change = 1.14% shrinkage in size of wood
This means that every piece of wood in a second hand imported Japanese
piano will shrink or be under stress to shrink just over 1% just
to meet USA/Australian standard.
Wood parts that can shrink include soundboard, action parts, cabinet
parts, tuning pin block and any part not glued to another part.
Wood that is under stress and trying to shrink includes parts that
are glued together like laminated wood. Even parts that are glued
together will shrink an amount and can finally break the glue joint.
60% Relative Humidity (RH) produces 11% EMC. 35% RH produces 7%
25% RH change produces 4% EMC change.
4% EMC change produces 1.14% size change.
Yamaha go to
enormous trouble to season their pianos for different climates.
They need to ensure that all the timber required to produce the
piano is ready at the same time, and then they produce pianos for
a particular climate. This means that orders need to be placed months
in advance from each country. After manufacture, the pianos are
kept for 14 days in a humidity controlled area in the factory to
stabilise. Then they are sealed in a moisture proof bag inside their
box, and shipped out. You can imagine all the extra work, planning
and therefore expense this causes. Yamaha would not do this unless
they knew it was important.
It is quite humorous that people selling second hand imported Yamaha
pianos actually will tell you to buy Yamaha because they are the
best pianos, and have the best action, and the best tuning stability,
the best sound etc, etc. This is clearly because Yamaha have done
such extensive research and use such precise manufacturing processes.
Then they will say to you "Oh, by the way, don't bother about
this made for Australia business - Yamaha don't know what they are
talking about" What a joke! Yamaha do know what they are talking
about, that's why they make the best pianos! You can't have it both
the experts on Yamaha pianos, and they are warning you not to buy
a second hand imported Yamaha. Don't be misled!
the expert on Yamaha pianos?
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