[pianotech] Totally glueless

[Ron Nossaman]

On 1/31/2013 10:24 AM, Ed Foote wrote:

> The restringing had nothing to do with the bridges.  This is a school
> piano, and lots of broken strings and iffy pins were sufficient reason.
>   The discovery of an unglued bridge was incidental.

And unsuspected from any perceived tonal deficiency. Okay, that's what I 
thought.


> The bottom of the
> bridge's apron was curved to match the soundboard's curve.

Okay, I guess.


>      Luthiers have long known that different ways of attaching necks
> have different sounding results. The integrity of the neck joint is
> widely recognized as having an effect on tone.

This is considerably different from bridge attachment, and has more to 
do with the rigidity of the string termination out there on a long beam 
than any suspect acoustical coupling.


> With only two screws holding the stucture
> together, there will be less coupling than fully glued.

Agreed, there obviously will though the mechanical coupling that was 
there could have been better with glue, it was apparently adequate to 
not draw attention to any lack of acoustic coupling - whatever that is 
exactly.


> If one is to
> believe that any coupling is as good as another, this won't matter.

One can and will believe what meets one's desires and needs, regardless, 
in my experience. Others try to determine what's real from evidence, so 
they don't have to depend on belief. The down side is that they can't 
have it the way they might wish it to be, but have to accept what they 
find, which puts them in a thinly populated corner of reality. I've 
tried to explain my reasoning, so how about describing to me what 
acoustic coupling is, how it differs from simple mechanical attachment, 
and how I might recognize it when I can't hear the difference.


>  The acoustic coupling is more difficult to measure.

Without a definition, I'd say it's impossible. How is it measured?


> If I decide that there must not be any difference
> because I can't hear it, then I am going to find less and less things
> that make a difference because 60 year old ears are no longer hearing
> the same as 30 year old ears.

That would probably be fewer and fewer things. I don't think things is a 
volume measurement in this instance. Regardless, if you can't trust your 
own ears, how can you in good conscience sell your services tuning and 
voicing?
Ron N