M&H Spyder - was Re: annoying posts - new solutions

[Ron Nossaman]

>	I service an old rebuilt M&H BB...a nice instrument. Down in the lower
>tenor close to the break there is a "noise" that sometimes sounds like
>an extraneous buzzing but on close examination seems to be more firmly a
>part of the piano. I wonder sometimes if it has to do with the torsion
>bars underneath. It is predominate on one note in particular. It's not
>in the hammer or voicing. 

That ought to be pretty easy to verify by wedging a chunk of felt between
the beam and rod everywhere they come close together and see if the noise
persists. If it does, that's not it. Being rebuilt, is there string braid
in the back scale of the low tenor? Weird groans and other odd Banshee
noises can result from this in some cases. Just like anything else, if it's
not immediately obvious what it is, you have to go looking for it. Get
someone to repeatedly strike the key that best invokes the noise while you
swarm over and under the instrument listening and touching everything you
can think of until you find it.  


>	How are those torsion bars torqued or tuned? I'm not thinking of
>messing with them...just want to know. I believe it's something to do at
>the time of building/rebuilding...like setting the plate. I am way off? 

They aren't torqued, or tuned. They are rim stiffeners. That's all, no
magic, no pixie dust, no deep dark secrets. They are intended to raise the
mechanical impedance of the rim as much as possible to reflect soundboard
energy back into the soundboard instead of letting a vibrating rim absorb
it. They are also not intended to, nor do they, maintain soundboard crown -
contrary to recent M&H advertising in the Journal to that effect. The lock
nuts ought to be tight, and no adjustments should ever be necessary, even
when they're rebuilt. I think it's a wonderful system, and in conjunction
with a maple rim and belly bar, would make for as solid a rim assembly as
you would find anywhere. Does anyone know  what wood the new M&H is using
for the belly bar?



>	I just tuned a S&S D for a concert last night - pretty great piano and
>new. I noticed that the last tenor note just before the break had a
>rather noticable bad overtone noise - for want of a better discription.
>I'm quite sure it was not from the duplex area or a problem at the
>agraffe. 
>	I put these two problems together as the noises are not that different
>from each other. This is to the best of my memory.
>	Comments?


It's not that uncommon to find zero or negative bearing at that point in
the D, and it sounds really nasty when that's the case. You might want to
check it. 

Ron N