Acoustic foam

[Tom Servinsky]

Sorry John, I guess I totally miss-understood your point. Sorry!
As far as the foam on the top, that does quiet things down quite a bit. So 
much so, the player feels like the piano is sounding from another room.
Here's my take on things:
The one's doing the most complaining are the ones who are doing the 
listening, not ones doing the playing. It's the overall volume taking over 
the household that bothers most listeners. Thus the foam on the bottom of 
the piano really retards the sound coming from that section of the piano. In 
our part of the world, we have a lot of extremely hard floors with no rugs 
or carpets under the piano ( marble and stone). The sounds bounces very 
quickly off of the bottom and shoots around the rooms in droves. Adding the 
foam will slow that problem down to a crawl. What's interesting is that the 
player can barely notice any difference in sound.
Adding the foam on the top adds another effect as it's  diminishes the sound 
to the player. If the piano is being strictly as a player piano, the foam on 
top will help tremendously. However, if the piano is going to be played by a 
pianist  they will be shocked with the diminished sound. If the piano is 
being used strictly  by a pianist, I will opt not to add foam to the top.
There's a psychologically phenomenon that occurs when the piano is being 
played by a person, as the piano is expected to be heard.
When the piano is being played by a player mechanism, people have a tendency 
to think the volume of the piano should behave like a stereo receiver. You 
should be able to go to a complete, distant, ambient sound of Volume 1. Of 
course, that's an impossibility when dealing with the complexities of a 
piano. But that's what I have been able to derive from the comments about 
volume and pianos.
It comes down to what your end games needs to be.
Tom Servinsky
----- Original Message ----- 
From: "John Formsma" <formsma at gmail.com>
To: "Pianotech List" <pianotech at ptg.org>
Sent: Sunday, November 04, 2007 8:09 PM
Subject: Re: Acoustic foam


> On 11/4/07, Tom Servinsky <tompiano at bellsouth.net> wrote:
>
>> There is a big difference between foam mattress material and acoustical
>> baffle foam.  Recording studios having been using this material for years 
>> to
>> insulate the interior space against outside noise. Can't say I have ever
>> seen a recording studio pad the walls with mattress foam. I'm not sure 
>> how
>> the acoustical/physical characteristics plays into the egg crate shape, 
>> but
>> it does contain sound extremely well.
>> That being said, any material (be it foam, blankets, or anything) is 
>> going
>> to aid in retarding sound from the bottom of the piano. The question is 
>> how
>> much containment of sound are you hoping for. We've experimented with 
>> just
>> about everything and for the extra money, the high grade acoustical 
>> baffle
>> foam is well worth the extra cost.
>
> I agree with you, Tom.  I was responding to what Israel said about
> using a foam mattress cut to size.  That will reduce the sound, but as
> I said, the acoustic foam is denser and would do a better job.
>
> What I was talking about was after the acoustic foam was in place on
> top and bottom.  I was wondering if a foam mattress might help *in
> addition* to what was already there. It did make a difference, but not
> significant enough.  Sorry if I worded it poorly.
>
> Having done my little experiment on that job, I will use acoustic foam
> in the future if ever I need to reduce the volume.
>
> Someone else before me had put a sheet of fiberglass insulation in
> there.  That doesn't work well at all, just in case anyone was
> wondering. <g>
>
> JF
>