OT: Question on Lesson Studios

[Keith Roberts]

Ron,  I believe my thought, as I understood the reasoning, was that if the
way the wall was built reduced the sound by 50%, then splitting the plates
might add another 10% and be noticeable. If the other factors in the wall
are done properly and the noise reduction reaches 90%, splitting the plates
has far less of an effect on the overall noise reduction and is not
important. By the same token, if the soundboard rib structure etc., is
designed to achieve the desired stiffness, the bridge stiffness becomes a
non factor. I hope that's what you guys meant, thanks for your polite
response.
On the soundproofing, fiberglass does have sound deadening properties but
takes up too much space in comparison to other materials and is hard to
eliminate holes. Since you pay by the square foot as measured from the
outside of the building, what you take up on the inside with your walls and
such can be expensive. If your walls are not structural and are basically
there to divide space and hold up the sheetrock, I wouldn't frame it with
any more than a 2 x 4s or even less. In the condos I have worked there is no
fiberglass in the walls between units. It's considered a waste of money.
Keith



----- Original Message -----
From: "Ron Nossaman" <RNossaman@cox.net>
To: <pianotech@ptg.org>
Sent: Wednesday, August 07, 2002 9:48 PM
Subject: Re: OT: Question on Lesson Studios


>
> >  I've been in the construction trades for 30 years and
> >only a few times have I ever seen the top and bottom plates split. This
is
> >because they are nailed solid and any sound transmission is through them
and
> >not due to the outside surfaces of the wall acting as one unit. It does
have
> >some effect but when the rest of the wall is built properly it is
> >negligible. I think that is the same argument Del and Ron use for not
gluing
> >the bridge on the soundboard in the crowned position.
>
>
> I'm not sure where this connects. Splitting a wall with sheetrock attached
> to every other stud from each side works by de-coupling the two sides of
> the wall, so the movement from one side doesn't directly move the other.
> Sound deadening panels do essentially the same thing. The movement of the
> surface picking up sound vibrations is absorbed and dissipated within the
> non-rigid interior of the panel instead of mechanically moving the
opposite
> surface along with it. If the perimeter of the wall is anchored in
> something either massive or absorptive, instead of another elastic
membrane
> like the wall surface, it shouldn't be a big problem. You lost me on the
> bridge, soundboard analogy. Where's the connection (as it were) there?
>
> Trying to keep up.
>
> Ron N
>
>