Recrowning

[Tom Myler]

> From: Richard Moody <remoody@easnetsd.com>

.......> 	Which brings to mind the Tension Resonator  invented by Richard
> Gertz and used in Mason and Hamlin grand pianos.   Never could figure
> out where "resonator" came from or denotes.  OR why no one else used
> it................


I'll take a shot at this, by attempting to paraphrase from a
talk/demonstration given by Chris Robinson several years ago.  WARNING:  My
memory is notoriously spotty, and famous for garbling details.    As
briefly as possible:

1)  Steinway's  basic rim  is a big open "U"  shaped piece,  slightly
narrow at the open end of the "U".    NO soundboard, braces, etc. yet.  And
we're viewing this theoretical rim from above.

2)  The pinblock and stretcher bar are longer than the width of the open
end of the U.   When they are in  place, they force the two ends of the U
further apart.   (That's why it's called a "stretcher" bar.)

3)  The entire rim is now under tension.    (If the stretcher and pinblock
were removed, the  resulting U would relax and the open end would spring
back to its original narrower size.)   This tension also "unifies" the rim,
soundboard, etc, into a single resonating system.

4)  This is part of the Steinway tone, sustain.  It's also one of the
reasons that older Steinways will so often have such surprisingly good tone
and sustain for their age and condition. (We've all seen this.)

5) Using small models with a removable "stretcher", and a tuning fork,
Chris demonstrated that any point on such a rim will be MUCH more resonant,
 when the stretching tension is in effect.

6) Chris suggested that we do the following test for ourselves.   Touch a
tuning fork to just about any spot on a Steinway rim, and hear how loud it
gets.    Try the same test on other non-Steinway pianos, and hear how the
rim doesn't resonate nearly as well.

7)  One piano that DOES have the same properties of tone and longevity is
Mason & Hamlin.  (Remember Mason & Hamlin?  This is a post about Mason &
Hamlin.)

8)  Reason:  the "Tension Resonator", which accomplishes the same effects
as 1
through 6 above.   The difference is that the Tension Resonator is inducing
tension by pulling the rim inward, rather than forcing it outward.

9)  Conclusion:  It's called the "Tension Resonator" because that's *how*
it does *what*
it does.

End of Chris Robinson notes.

My thoughts-

10)  All of the lore about M&H soundboards not losing crown because the rim
can't expand and so forth is beside the point.  If the TR has that effect
on a soundboard, it's an incidental fringe benefit, but is not the reason
for, or purpose behind  the TR.   Note that it was never called the "Rim
Stabilizer" or "Krown Keeper".   That was never the point.


DISCLAIMER:   If  I'm  wrong about any of this, it's YOUR  problem for not
having deleted me.   I reserve the right to be wrong.

Sorry for the length of this post,  blah, blah.


Myler, Tom

"Perhaps the greatest wisdom is the knowledge
of one's own ignorance"

                                 John Steinbeck


P.S.   This List needs MORE of Jim Coleman Sr.,  not less.