Sound- absorption or reflection

[Bill Garamella]

Last year I insulated the doghouse of our 1983FC doghouse with 2" 2#/ft. sq.
fiberglass
and lead material that I purchased from Soundown. I followed the instructions
provided
by their rep Gary Kissal and am very happy with the results.

I have been speaking with Gary on how best to quiet down the 12.5 Yanmar/Kohler
and
he suggested several things:

To quiet outside noise, create a baffle between the fan and the exhaust louvers.

To quiet inside:

1. Apply mechanical fasteners to all surfaces to be covered
2. Apply adhesive damping material against the metal inside the generator
compartment.

"Soundown Vibration Damping Sheets and Tiles are a high performance, easily
applied,
extensional vibration dampers for reducing structural reverberant "ringing" and
structureborne noise. This material is effective on a wide range of substrates,
especially
fiberglass, aluminum, and steel. Soundown Damping Sheets are available in 1/16",
1/8",
1/4" at 54" width, and in 1'x 1' tiles in 3/8" and 1/2". We also stock a
complete line of
interlayer damping materials for many applications."

3. Apply 2" 2# ft./sq. composite insulation onto the damping material using both
mechanical fasteners and adhesive.

"Soundown's Mass Loaded Vinyl Barrier (Tuff Mass®) is available in 1/2, 1,
1-1/2, and 2
lb/ft2 densities. It is a rugged all-purpose sheet barrier with a wide range of
uses. Our
Mass Loaded Vinyl is supplied in a standard 54" and 48" width and variable roll
lengths
from 10' to 250' depending upon material configuration. Soundown Acoustic Lead
Barrier
is available in weights of 1 and 2 lb. This traditional incombustible barrier
material is
supplied in a standard 48" width, and rolls of 12', 24', or longer as required."

I have no material interest in the company other than being a very satisfied
customer.
Their exclusive function is to quiet things down and they have been doing it for
a very
long time with very expensive marine craft, and high end structures.

Here is a link to their web site. http://www.soundown.com/AI.htm#

Garry Kissal's e-,mail is gkissal@...

In lieu of the baffle which I think will be too much work, I plan to install a
quiet plastic
DC fan to the radiator (like in a car) and an aqua-stat that will keep the big
AC fan off
until higher temps are reached. I suspect this will help a lot and much of the
time we
run our genset at way less than half load.

Another factor is the use of a ProSine 2K inverter that also helps to minimize
gen run
time.

NH Bill 1983 FC "Casa Billisa"


--- In WanderlodgeForum@yahoogroups.com, "Stephen Birtles" wrote:
>
> if you look at the newer generators the sound deadening box has
> baffled vents and is sealed as well as sound deadening
> materials,thermostatically controlled fans and a smaller new motor
> with indirect indirect injection. With all these it makes for a
> quieter generator
>
> Stephen 77fc35
>
>
>
> --- In WanderlodgeForum@yahoogroups.com, Ernie Ekberg
> wrote:
> >
> > Jim, while the some of the noise was deflected down, 30 more db was
> reflected to the front of the radiator. Bob's coach has the front
> fan/radiator.
> >
> >
> > Ernie Ekberg
> > 83PT40
> > Wanderlodge
> > Weatherford, Tx
> > http://autos.groups.yahoo.com/group/erni...gandrepair
> >
> > --- On Fri, 2/20/09, jim riordan wrote:
> >
> > From: jim riordan
> > Subject: Re: [WanderlodgeForum] Sound- absorption or reflection
> > To: WanderlodgeForum@yahoogroups.com
> > Date: Friday, February 20, 2009, 10:01 PM
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > I would assume that the sound deading material used in these
> generator compartments actually reflect the nooise down. so the noie
> is forced under the coaches. Many boats and I belive that some new
> coaches now have a box lined with sound deading which the generator is
> placed.
> >
> > just a thought
> >
> > jim riordan
> > 88 wbwl xxv
> > stuart fl
> >
> > --- On Fri, 2/20/09, Ernest Ekberg wrote:
> >
> > From: Ernest Ekberg
> > Subject: [WanderlodgeForum] Sound- absorption or reflection
> > To: WanderlodgeForum@ yahoogroups. com
> > Date: Friday, February 20, 2009, 7:43 PM
> >
> >
> >
> >
> > After installing many generator compartments with the new insulation, I
> > was wondering if there is a manufacturer that offers both.
> > I insulated Bob Lawrences' generator compartment last December. He
> > measured the db levels before and after and found that while the heat
> > was reflected from the interior of the coach, the sound was also
> > deflected to the outside. thus his db levels INCREASED to over 90.
> > I know my with my coach, that I have been asked to park way downwind as
> > my generator is really loud. Maybe its the dogs I carry with me???
> > But, if there is a product that will absorb that sound while reflecting
> > the heat, let's talk about it.
> > Ernie-83PT40 in Texas, buying earplugs by the case~
> >
>