Wild strings in new pianos

[Ron Nossaman]

>Ron et al,
>
>I have tried treating some suspected bridge "softies" with saturations of CA
>glue. I tried removing bridge pins and not rmoving bridge pins. Results
>seemed somewhat mixed, but I would say that a great many wild or false
>beating strings were reduced to whispers or cleared up entirely. Of course,
>before trying this on a new piano I believe it would be prudent to get the
>manufacturer's approval, possible in writing before trying that method. I
>also think other areas of string termination should be well checked out
>first, such as poor or kinked wire, clean notches and good placement of
>bridge pins to the notch, cleanly defined capo bar termination and listening
>for sympathetic string vibration problems from other areas of the piano. I
>also believe that you should proceed with a good tuning first before
>deciding on a course of action, as many mysterious wild strings will be
>adequately masked upon close coupling of the unison. I guess we're running
>out of 300 year old rock maple trees with close grain characteristics.
>Synthetics anyone?
>
>Just my two cent's worth.
>
>Joseph Alkana 
>

By all means, contact the manufacturer, but do it *after* you have done the
screwdriver test and verified that the noises are the result of loose bridge
pins. If the screwdriver test has no affect, it's not loose pins. Always
start with the high probability, quick, easy, and non destructive tests
first and work out from there until you find the problem. When you find a
cause - stop. Check for loose pins before tapping any strings down. Seating
strings on loose bridge pins will often seem to improve the sound, but it's
a temporary improvement, and not a "fix", because it masks the symptoms
without correcting the real problem. Also, if you have done *anything* else
to the piano except verifying loose bridge pins, you will never get a
manufacturer to acknowledge the problem. You probably won't get any
manufacturer to admit even the possibility no matter how much evidence you
have anyway, but why make it easy on them? %-) They will *always* recommend
seating the strings on the bridge because it usually does help temporarily,
and postpones the issue. All bridge pins in all new wooden bridges will
eventually loosen as wood fibers are distorted and crushed by dimensional
changes with humidity shifts. Bridges aren't any different in this regard
than soundboards and action parts. The harder the cap material, the tighter
the assembly tolerances, and the narrower the humidity swings suffered since
assembly, the tighter the pins will be on delivery to the customer. A pin
that was driven into a less than tight hole in a too soft bridge cap, and
suffering a couple of 50% RH swings (under string tension) before final
delivery, will have loose bridge pins and wild strings. It's normally only a
problem through octave 5 and 6 as the bearing usually increases in the
extreme treble to the point where the string is anchored to the bridge
surface firmly enough that the loose pin doesn't have much effect. Below
octave 5, either the string mass is too high, or the frequencies are too low
(I'm not sure which), for loose pins to have a detrimental affect.

That's my take.  

 Ron