Steinway Sustain

[Delwin D Fandrich]

----- Original Message -----
From: "Tony Caught" <caute@optusnet.com.au>
To: <pianotech@ptg.org>
Sent: April 18, 2001 4:42 AM
Subject: Re: Steinway Sustain




> You are confirming my opinion that the 'killer octave' is caused by other
> than the action it total and that the problem has to be addressed in other
> areas first. As you point out, the soundboard is the problem or the string
> to soundboard area is the problem.
> Possible causes, aliquot bar to low, string contact with bridge, bridge
> weakened at this area, bridge soundboard contact not solid, rib or ribs
weak
> in affected area, soundboard thinned in affected area, soundboard
distorted.

You can pretty much rule out the aliquot bar to low, string contact with the
bridge, bridge weakened at this area, bridge soundboard contact not solid,
etc., as being the cause of the tone problems you originally described.

But you will find the ribs to be fairly 'weak.' They are -- of necessity --
somewhat flexible in a compression-crowned board. Remember, the ribs have to
bend easily enough for the expanding soundboard panel to force them into a
curve (the crown). Unless there is some crown physically cut into them, ribs
in these boards do not support crown; they resist it.

You will also find the wood fibers fairly well compressed -- due to
compression set -- in the soundboard panel if the piano is more than a
couple of seasons old. Especially so if the panel has been thinned through
this region. And you may find the soundboard to be distorted.



> Will try the weight idea first to see if it will improve the sustain/tone
of
> this area and if so, what is your opinion in thickening the ribs in the
> affected area or in stiffing the ribs. would this do the same thing as
> hanging a weight ?

Well, this goes back to the old idea of adding springs to the system.
Although the idea has been pretty thoroughly ridiculed over the years by
many of the more proper technicians, I'm not sure it's such a bad idea.
Since it is soundboard stiffness that is lost through the compression-set of
the wood fibers in the soundboard panel, why not at least attempt to add
some back through the use of an auxiliary spring? I'm not altogether sure
the soundboard can tell the difference. At least it's easily removable if it
doesn't work and, if you've been careful, no one will ever know you've been
down there. Several of us semi-old-timers have experimented with this over
the years. Let me know if you're interested in pursuing the subject.

Del