heretical on soundboards

[Delwin D Fandrich]

Frank Weston wrote:
> 
> Many old soundboards have held up well because they were made from the
> best wood (wood that may no longer be available), further, great
> attention was given to properly seasoning that wood. I read somewhere
> that years back, the most important job at Steinway, one always reserved
> for a family member, was the selection and purchase of wood.
> 
> Today, the wood used in most soundboards is selected from faster growing
> species, not as much high quality wood is always available, and economic
> pressures preclude expensive and time consuming seasoning methods. (I
> expect a little argument on this point from the manufacturer's reps)

This is certainly part of the problem. Whether we like it or not our
forests will never be what they were 100 years ago. At least not in our
lifetimes—we’ve done far too much damage to them. Neither will wood
processing—the priorities of the wood industry have changed far too much
for that. This doesn't mean we have to give up on the piano, though. If
you believe that the piano is still an evolving instrument (as I do)
then you can appreciate that there are many avenues still open to
us—both with materials available to us and perhaps even more, with
innovative design. Soundboards can be—have been—developed that can cope
with modern life and at the same time provide better sound than their
predecessors. Even wood soundboards. I’m far from giving up on our Sitka
spruce soundboards.


> Bottom line: today's soundboards may in general be less durable than
> those of 100 years ago.  The method of finishing is of little
> consequence to long term durability.

I don’t agree that the soundboards we’re putting in pianos today are any
less durable than those installed in pianos 100 years ago. I fully
expect them to have a useful (musical) life that is at least as long
even though I’ll not be around to prove it.


> To add more fuel to the fire:  Why do a lot of old soundboards that have
> seen coal heat, high humidity, low humidity, and in general a lot of
> abuse endure without a complaint, when new soundboards fitted with
> humidity control systems frequently show signs of deterioration within a
> few years?

I don’t necessarily agree that they’ve survived without complaint. Again
I must say that we’re trying to use the exceptions to try to prove the
rule. The practice of compression crowning soundboards is not as precise
as many factories would like us to believe. There are a lot of potential
variables. Individual soundboards survive because they were bellied in
such a manner that exposure to normal atmospheric conditions did not
cause them to exceed their structural capabilities. I suspect—though
again, can’t prove—that these boards had the serendipitous combination
of particularly resilient wood plus being bellied at the high end of the
relative moisture content scale. In the case of those soundboards
finished with shellac, of course, you are right: the finish didn’t have
anything to do with the soundboards longevity. (Sorry. Just couldn’t
resist that!)

As an aside, I once  repaired a soundboard in a Japanese built piano
that was located in a home in the Nevada high desert. In the winter,
with a forced air heating system going and with no moisture being added
to the room—I didn’t measure the relative humidity in the room, but it
was DRY!—the soundboard had developed the mother of all  “compression
ridges.” It formed an inverted “V” along a glue line running down the
middle of the board. It had pulled away from the ribs for a distance of
about 25 to 50 mm on either side of the glue line. It had forced itself
up so that I could measure a gap of about 10 to 12 mm between the top of
the rib and the bottom of the soundboard. I have no idea what the
moisture content must have been in this soundboard when it was bellied,
but it must have been close to oven dry. 

My point is that manufacturers don’t—can’t, really—always control this
process as well as they might like to. It is very difficult to
accurately control the relative humidity of a room, even a wood
conditioning room. And it’s very difficult to control the moisture
content of wood all that precisely. It can be done, but it’s not easy.
The meters used to measure EMC usually don’t even read below 6% or so. 

As long as manufacturers depend on the practice of compression crowning
soundboards, there is going to be a high failure rate. “Failure” in the
sense of soundboards with compression ridges and cracks, not necessarily
musically. The two don’t always go hand in hand.

Regards,

ddf