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dude-guy
September 25th 08, 04:31 PM
Hi,

I desperately need an opinion from someone with a good understanding
of materials or noise reduction in general.

I live close to a church and the church bell makes extreme loud noise.
The noise is really loud, going through my windows. I want to put an
extra layer of window - obviously it should be transparent. Should
this extra layer be real "window glass" or polymeric/plastic "PMMA"?

Which transparent material reduces "church bell" sound waves the most?
I was told these guys make something that can reduce noise:
http://www.altuglas.com

Which frequencies do I need to reduce (freq. of sound from church
bell)?

How about optimal layer thickness of the transparent material?

Hope somebody is clever enough to help me find the best solution...

Androcles[_3_]
September 25th 08, 04:44 PM
"dude-guy" > wrote in message
...
> Hi,
>
> I desperately need an opinion from someone with a good understanding
> of materials or noise reduction in general.
>
> I live close to a church and the church bell makes extreme loud noise.
> The noise is really loud, going through my windows. I want to put an
> extra layer of window - obviously it should be transparent. Should
> this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> Which transparent material reduces "church bell" sound waves the most?
> I was told these guys make something that can reduce noise:
> http://www.altuglas.com
>
> Which frequencies do I need to reduce (freq. of sound from church
> bell)?
>
> How about optimal layer thickness of the transparent material?
>
> Hope somebody is clever enough to help me find the best solution...

Best solution... dynamite the useless ****in' church, bell and all.
Second best solution: sell your house to a campanologist then go
live next to an airport. My problem is noisy traffic, especially buses,
but double glazing is adequate unless I open a window.

Angelo Campanella
September 25th 08, 06:18 PM
dude-guy wrote:
> I live close to a church and the church bell makes extreme loud noise.
> The noise is really loud, going through my windows. I want to put an
> extra layer of window - obviously it should be transparent. Should
> this extra layer be real "window glass" or polymeric/plastic "PMMA"?

Do NOT waste money on plastic products, as the mass (weight) is the
only sound reducing entity that will help, and glass is cheaper by the
pound.

> Which transparent material reduces "church bell" sound waves the most?
> I was told these guys make something that can reduce noise:
> http://www.altuglas.com

Simply add thick glass "storm windows to the windows facing the bell
tower, and on windows on facades that are at right angles to same.

> Which frequencies do I need to reduce (freq. of sound from church
> bell)?

The bell tones, likely above about 200 Hz, but that varies with size.

There is another aspect: Recently, pastors have become enamored with
electric bell chimes. Some believe they do the community a favor by
operating them loudly and frequently. Determine whether this is the case
for your location. If so, then register a complaint to the church
administration, that their chime operation is annoying to the residents.
Perhaps they could reduce it a a single daily Angelus at noon or 6pm.

Angelo Campanella

dlzc
September 25th 08, 06:41 PM
Dear dude-guy:

On Sep 25, 8:31*am, dude-guy > wrote:
....
> Which frequencies do I need to reduce (freq. of sound
> from church bell)?

2000 Hz and down, usually.

> How about optimal layer thickness of the transparent
> material?

Give up. You need a second wall and ceiling, with mechanical
isolation between the two.

> Hope somebody is clever enough to help me find the
> best solution...

Most economical solutions:
1) move.
2) attend the church.
3) noise cancelling headphones.
4) join the Hells Angels, and make sure to circle the church during
services.
5) remove the striker.
6) coat the striker with contact explosive.
7) fire / throw massive objects at the bell when the minister /
preacher / priest is conducting services.

Some of those might involve some jail time...

David A. Smith

Androcles[_3_]
September 25th 08, 07:10 PM
"dlzc" > wrote in message
...
Dear dude-guy:

On Sep 25, 8:31 am, dude-guy > wrote:
....
> Which frequencies do I need to reduce (freq. of sound
> from church bell)?

2000 Hz and down, usually.

> How about optimal layer thickness of the transparent
> material?

Give up. You need a second wall and ceiling, with mechanical
isolation between the two.

> Hope somebody is clever enough to help me find the
> best solution...

Most economical solutions:
1) move.
2) attend the church.
3) noise cancelling headphones.
4) join the Hells Angels, and make sure to circle the church during
services.
5) remove the striker.
6) coat the striker with contact explosive.
7) fire / throw massive objects at the bell when the minister /
preacher / priest is conducting services.

Some of those might involve some jail time...

David A. Smith
==========================================
Ringing hand bells in church during services or overturning
the money changer's passed plate could be amusing.

Clyde Slick
September 25th 08, 07:16 PM
On Sep 25, 1:41*pm, dlzc > wrote:
> Dear dude-guy:
>
> On Sep 25, 8:31*am, dude-guy > wrote:
> ...
>
> > Which frequencies do I need to reduce (freq. of sound
> > from church bell)?
>
> 2000 Hz and down, usually.
>
> > How about optimal layer thickness of the transparent
> > material?
>
> Give up. *You need a second wall and ceiling, with mechanical
> isolation between the two.
>
> > Hope somebody is clever enough to help me find the
> > best solution...
>
> Most economical solutions:
> 1) move.
> 2) attend the church.
> 3) noise cancelling headphones.
> 4) join the Hells Angels, and make sure to circle the church during
> services.
> 5) remove the striker.
> 6) coat the striker with contact explosive.
> 7) fire / throw massive objects at the bell when the minister /
> preacher / priest is conducting services.
>
> Some of those might involve some jail time...
>
>

Prisons can be quite noisy, too, from what
I have seen on reality tv shows.
Sorry, but I have no personal experience.
Besides, this poor guy just might
have the misfortune to be housed
in a prison right next to a church, the worst of both worlds.

hwabnig@ .- --- -. dotat
September 25th 08, 08:26 PM
On Thu, 25 Sep 2008 08:31:08 -0700 (PDT), dude-guy
> wrote:

>Hi,
>
>I desperately need an opinion from someone with a good understanding
>of materials or noise reduction in general.
>
>I live close to a church and the church bell makes extreme loud noise.
>The noise is really loud, going through my windows. I want to put an
>extra layer of window - obviously it should be transparent. Should
>this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
>Which transparent material reduces "church bell" sound waves the most?
>I was told these guys make something that can reduce noise:
>http://www.altuglas.com
>
>Which frequencies do I need to reduce (freq. of sound from church
>bell)?
>
>How about optimal layer thickness of the transparent material?
>
>Hope somebody is clever enough to help me find the best solution...

Convert to Islam and do muezzin exercises calling for prayer,
when they ring the bells, that is.

w.

Androcles[_3_]
September 25th 08, 08:48 PM
<hwabnig@ .- --- -. dotat> wrote in message
...
> On Thu, 25 Sep 2008 08:31:08 -0700 (PDT), dude-guy
> > wrote:
>
>>Hi,
>>
>>I desperately need an opinion from someone with a good understanding
>>of materials or noise reduction in general.
>>
>>I live close to a church and the church bell makes extreme loud noise.
>>The noise is really loud, going through my windows. I want to put an
>>extra layer of window - obviously it should be transparent. Should
>>this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>>
>>Which transparent material reduces "church bell" sound waves the most?
>>I was told these guys make something that can reduce noise:
>>http://www.altuglas.com
>>
>>Which frequencies do I need to reduce (freq. of sound from church
>>bell)?
>>
>>How about optimal layer thickness of the transparent material?
>>
>>Hope somebody is clever enough to help me find the best solution...
>
> Convert to Islam and do muezzin exercises calling for prayer,
> when they ring the bells, that is.
>
> w.

Wabbie, that is the most intelligent and humorous reply I've seen.
How come you are such a dickhead when it comes to physics?

±[_2_]
September 26th 08, 04:08 AM
you're an asshole

±[_2_]
September 26th 08, 04:16 AM
In my business, we built to rooms to house punch presses which are very
loud when they are running. The rooms are standard 2x4 construction.
They have large 4 x 8 windows in them on two walls. The windows are
created by two sheets of 1/8 thick polycarbonate separated by 3" of air
in between them. Everyone is surprised at how quiet the presses are
even close proximity to others working. Subjectively, these double
windows seem to dampen the noise at least as well as the rest of the
enclosure. For what it's worth.


> Hi,
>
> I desperately need an opinion from someone with a good understanding
> of materials or noise reduction in general.
>
> I live close to a church and the church bell makes extreme loud noise.
> The noise is really loud, going through my windows. I want to put an
> extra layer of window - obviously it should be transparent. Should
> this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> Which transparent material reduces "church bell" sound waves the most?
> I was told these guys make something that can reduce noise:
> http://www.altuglas.com
>
> Which frequencies do I need to reduce (freq. of sound from church
> bell)?
>
> How about optimal layer thickness of the transparent material?
>
> Hope somebody is clever enough to help me find the best solution...

dude-guy
September 26th 08, 12:55 PM
On 25 Sep., 19:18, Angelo Campanella > wrote:
> dude-guy wrote:
> > I live close to a church and the church bell makes extreme loud noise.
> > The noise is really loud, going through my windows. I want to put an
> > extra layer of window - obviously it should be transparent. Should
> > this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> * * * * Do NOT waste money on plastic products, as the mass (weight) is the
> only sound reducing entity that will help, and glass is cheaper by the
> pound.

That was also my first thought, until I got contact with a company who
says they successfully had used some PMMA plastic material from
http://www.altuglas.com/ - however I'm still in doubt about what to
do, as I would like a "neutral opinion" and this guy I talked to, he
was a seller...

Are you completely sure mass is the only thing to consider?

If that is the case, I would just go for a glass material with very
high density - and perhaps in all cases use 2 layers... If I have to
use more layers, it'll become very ugly...

Does it matter whether it's high or low frequent noise?

My immediate idea is that high frequency noise perhaps can be filtered
with plastics (PMMA), but perhaps low frequency noise cannot and needs
mass...

> > Which transparent material reduces "church bell" sound waves the most?
> > I was told these guys make something that can reduce noise:
> >http://www.altuglas.com
>
> * * * * Simply add thick glass "storm windows to the windows facing the bell
> tower, and on windows on facades that are at right angles to same.

I agree, it sounds like a solution. Does that kind of glass you're
talking about has a special name other than "storm glass"?

> > Which frequencies do I need to reduce (freq. of sound from church
> > bell)?
>
> * * * * The bell tones, likely above about 200 Hz, but that varies with size.
>
> * * * * There is another aspect: Recently, pastors have become enamored with
> electric bell chimes. Some believe they do the community a favor by
> operating them loudly and frequently. Determine whether this is the case
> for your location. If so, then register a complaint to the church
> administration, that their chime operation is annoying to the residents.
> Perhaps they could reduce it a a single daily Angelus at noon or 6pm.

This one is definately not electrical. I know that for sure after
having talked to them and complained... It's operated manually and I
can see the bell vibrate, while the noise is bugging me for every bell
chime...

Tony[_3_]
September 26th 08, 01:00 PM
dude-guy wrote:
> Which transparent material reduces "church bell" sound waves the most?

If you are using a single sheet, the answer is acoustic laminated glass, the
thicker the better. However I assume you will be adding a layer to your
existing windows. In this case acoustic laminated glass might not be worth
its extra cost. You should use ordinary glass, the thicker the better - I
would suggest 10 mm or 3/8 inch. In ordinary buildings it is not usually
worth going above this as sound will also come through the rest of the
structure, air leaks, doors etc. (Don't expect silence!) The gap between
the new pane and the existing should be as much as you can manage up to 150
mm max. Don't go for plastic if you want much useful effect, you need
weight.

It will also help a lot if the space around the edge between the two panes
is lined with sound absorbent material, for example sound absorbing plastic
foam. Also if you do this you will still get a bit of noise reduction even
if you have openings for air, provided that the openings are not opposite
each other.
--
Tony W
My e-mail address has no hyphen
- but please don't use it, reply to the group.

OG
September 26th 08, 01:28 PM
"dude-guy" > wrote in message
...
> Hi,
>
> I desperately need an opinion from someone with a good understanding
> of materials or noise reduction in general.
>
> I live close to a church and the church bell makes extreme loud noise.
> The noise is really loud, going through my windows. I want to put an
> extra layer of window - obviously it should be transparent. Should
> this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> Which transparent material reduces "church bell" sound waves the most?
> I was told these guys make something that can reduce noise:
> http://www.altuglas.com
>
> Which frequencies do I need to reduce (freq. of sound from church
> bell)?
>
> How about optimal layer thickness of the transparent material?
>
> Hope somebody is clever enough to help me find the best solution...

Have you found this web page ?
http://irc.nrc-cnrc.gc.ca/pubs/cbd/cbd240_e.html

Basically, you want to add a secondary glazing layer with a wide gap between
the existing glass and the new glass. If you have different thicknesses of
glass for each layer you can increase the sound deadening effect. The amount
of noise insulation will depend on your window frame material as well. Wood
is good, thin metal is worse, it is possible to add sound deadening fillings
to hollow frames.

Using laminated glass can provide increased noise insulation compared to
plain glass.

N:dlzc D:aol T:com \(dlzc\)
September 26th 08, 02:09 PM
Dear dude-guy:

"dude-guy" > wrote in message
...
On 25 Sep., 19:18, Angelo Campanella >
wrote:
....
>> > Should this extra layer be real "window glass" or
>> > polymeric/plastic "PMMA"?
>
>> Do NOT waste money on plastic products, as the
>> mass (weight) is the only sound reducing entity
>> that will help, and glass is cheaper by the pound.

> That was also my first thought, until I got contact
> with a company who says they successfully had
> used some PMMA plastic material from
http://www.altuglas.com/
> - however I'm still in doubt about what to do, as I
> would like a "neutral opinion" and this guy I talked
> to, he was a seller...
>
> Are you completely sure mass is the only thing
> to consider?

Only thing, no. The material's ability to dampen vibration (good
for polymer, poor for glass), and mechanical isolation. Triple
paned glass is like a wall, for both sound and heat transfer
(well...)

> Does it matter whether it's high or low frequent
> noise?

The spacing between panes will decide whether it dampens /
isolates or resonates / amplifies the noise.

David A. Smith

GregS[_3_]
September 26th 08, 03:41 PM
In article >, dude-guy > wrote:
>Hi,
>
>I desperately need an opinion from someone with a good understanding
>of materials or noise reduction in general.
>
>I live close to a church and the church bell makes extreme loud noise.
>The noise is really loud, going through my windows. I want to put an
>extra layer of window - obviously it should be transparent. Should
>this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
>Which transparent material reduces "church bell" sound waves the most?
>I was told these guys make something that can reduce noise:
>http://www.altuglas.com
>
>Which frequencies do I need to reduce (freq. of sound from church
>bell)?
>
>How about optimal layer thickness of the transparent material?
>
>Hope somebody is clever enough to help me find the best solution...

Do you now have a energy double panned window. Thats the first step.


greg

OG
September 26th 08, 04:37 PM
"GregS" > wrote in message
...
> In article
> >,
> dude-guy > wrote:
>>Hope somebody is clever enough to help me find the best solution...
>
> Do you now have a energy double panned window. Thats the first step.

Double Glazing for sound reduction requires a significantly wider gap than
DG for heat loss reduction.

OG
September 26th 08, 04:51 PM
"OG" > wrote in message
...
>
> "GregS" > wrote in message
> ...
>> In article
>> >,
>> dude-guy > wrote:
>>>Hope somebody is clever enough to help me find the best solution...
>>
>> Do you now have a energy double panned window. Thats the first step.
>
> Double Glazing for sound reduction requires a significantly wider gap than
> DG for heat loss reduction.

Forgot to add
Mind you I'm not an acoustic engineer so I'm happy to be corrected!

Tony[_3_]
September 26th 08, 11:38 PM
"Asbjørn" > wrote in message
...
(sensible suggestions, but only in alt.sci.physics.acoustics)

I've set this back to all the original groups in case the OP isn't reading
alt.sci.physics.acoustics.
I see that a reasonably consistent consensus of technical opinion is now
appearing. The system does work sometimes!
--
Tony W
My e-mail address has no hyphen
- but please don't use it, reply to the group.

OG
September 27th 08, 01:52 AM
"Tony" > wrote in message
om...
> "Asbjørn" > wrote in message
> ...
> (sensible suggestions, but only in alt.sci.physics.acoustics)
>
> I've set this back to all the original groups in case the OP isn't reading
> alt.sci.physics.acoustics.
> I see that a reasonably consistent consensus of technical opinion is now
> appearing. The system does work sometimes!
> --
> Tony W

So far as I can tell, the only posting that is isn't in most threads is
Asbjørn's . Suggest the OP goes to a.s.p.a for the missing post.

Angelo Campanella
September 27th 08, 06:15 AM
dude-guy wrote:
>> Do NOT waste money on plastic products, as the mass (weight) is the
>>only sound reducing entity that will help, and glass is cheaper by the
>>pound.
> That was also my first thought, until I got contact with a company who
> says they successfully had used some PMMA plastic material from
> http://www.altuglas.com/ - however I'm still in doubt about what to
> do, as I would like a "neutral opinion" and this guy I talked to, he
> was a seller...

Plastic will be more expensive than glass except for the thinnest of
plastic sheets, little more than 1/16" thick, which is very light.

> Are you completely sure mass is the only thing to consider?

for high noise attenuation, it is the best.

> If that is the case, I would just go for a glass material with very
> high density - and perhaps in all cases use 2 layers... If I have to
> use more layers, it'll become very ugly...

I would not bother with "high density glass" since it may be pricey,
and may be more apt to crack. I recommend conventional window glass
since it is tempered for window usage.

Ordinary window pane glass is called "single strength" (SSG). it's
barely over 1/6" thick, perhaps 3/32" thick. Heavier window glass is
called "double strength glass" (DSG). This, I think, is what is used for
most larger storm windows. It's about 1/8" thick, I think. The next step
up is 3/16" plate glass, then 1/4" plate glass, etc.

> Does it matter whether it's high or low frequent noise?

To some extent it does. first of all, the heaviest glass is required to
stop low frequency noise (drums, boom boxes and car stereo thumping).
Less mass is needed for mid frequencies, but it may still be necessary
when you want a high degree of noise reduction. An anomaly occurs at the
"coincidence frequency" for a stiff plate such as glass, where it will
transmit sound in a narrow band around 2,000 to 2,000 Hz. In this regard
the plastic sheet, as light as it is, has a coincidence frequency at or
above 10,000 Hz, which is of no consequence. A good compromise is one
pane of thick plastic combined with a glass pane with a 2" gap inside.
This makes for a thicker package.

> My immediate idea is that high frequency noise perhaps can be filtered
> with plastics (PMMA)

OK.. combo of coincidence frequency being out of the picture, but it
only works well for high frequency sound.

, but perhaps low frequency noise cannot and needs
> mass...

Yes.

> I agree, it sounds like a solution. Does that kind of glass you're
> talking about has a special name other than "storm glass"?

The SSG and DSG and thicker panes were described. There is no such
thing as storm glass. To be sure, one could tag that name onto plastic
since it is more robust in high winds. (But plastic is troublesome in
very cold air since it shrinks much more than does glass, so the edge
clamping strip and frame have to be wider.)

>> The bell tones, likely above about 200 Hz, but that varies with size.

You would have to try a storm window, either store-bought or built by
you. It should be located as far as possible from the existing window
pane.; at least 2" and preferably 4" or more if possible. In the "old
days" (when I was growing up), the first storm windows I saw were framed
to the molding around the window on the outside facade. These make the
best noise attenuator. since the air gap is then many inches, and the
glass used ware DSG for surviving the winter blasts, etc..


> This one is definately not electrical. I know that for sure after
> having talked to them and complained... It's operated manually and I
> can see the bell vibrate, while the noise is bugging me for every bell
> chime...

It's intended to be heard for great distances...


Angelo Campanella

Arny Krueger
September 27th 08, 06:54 PM
"GregS" > wrote in message


> Do you now have a energy double panned window. Thats the
> first step.


Good point. I've seen numerous examples where ordinary vinyl storm windows
do a wonderful job of attenuating ambient noise. The spacing may not be
optimal, but they still work a treat.

Clyde Slick
September 28th 08, 02:44 AM
On 27 Sep, 13:54, "Arny Krueger" > wrote:
> "GregS" > wrote in message
>
>
>
> > Do you now have a energy double panned window. Thats the
> > first step.
>
> Good point. I've seen numerous examples where ordinary vinyl storm windows
> do a wonderful job of attenuating ambient noise. The spacing may not be
> optimal, but they still work a treat.

Listen to Arny, he is the expert on bad
noises emanating from churches.

GregS[_3_]
September 29th 08, 01:34 PM
In article >, "OG" > wrote:
>
>"GregS" > wrote in message
...
>> In article
>> >,
>> dude-guy > wrote:
>>>Hope somebody is clever enough to help me find the best solution...
>>
>> Do you now have a energy double panned window. Thats the first step.
>
>Double Glazing for sound reduction requires a significantly wider gap than
>DG for heat loss reduction.


Just going by experiance when i experianced new windows in the old house.

How about two sets of doubled glazed separated by a few inches ?

greg

N:dlzc D:aol T:com \(dlzc\)
September 29th 08, 02:10 PM
Dear GregS:

"GregS" > wrote in message
...
> In article >, "OG"
> > wrote:
>>"GregS" > wrote in message
...
>>> In article
>>> >,
>>> dude-guy > wrote:
>>>>Hope somebody is clever enough to help me
>>>>find the best solution...
>>>
>>> Do you now have a energy double panned
>>> window. Thats the first step.
>>
>>Double Glazing for sound reduction requires
>>a significantly wider gap than DG for heat
>>loss reduction.
>
> Just going by experiance when i experianced
> new windows in the old house.
>
> How about two sets of doubled glazed
> separated by a few inches ?

You will gain little more by a second double pane... since the
wall is also a transmitter of sound.

My wife gained a bit of thermal insulation and sound deadening by
stapling blankets over certain (exterior) walls, and covering
them with fabric that looked like wall paper.

David A. Smith

dude-guy
September 29th 08, 02:21 PM
On 26 Sep., 14:28, "OG" > wrote:
> "dude-guy" > wrote in message
>
> ...
>
>
>
> > Hi,
>
> > I desperately need an opinion from someone with a good understanding
> > of materials or noise reduction in general.
>
> > I live close to a church and the church bell makes extreme loud noise.
> > The noise is really loud, going through my windows. I want to put an
> > extra layer of window - obviously it should be transparent. Should
> > this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> > Which transparent material reduces "church bell" sound waves the most?
> > I was told these guys make something that can reduce noise:
> >http://www.altuglas.com
>
> > Which frequencies do I need to reduce (freq. of sound from church
> > bell)?
>
> > How about optimal layer thickness of the transparent material?
>
> > Hope somebody is clever enough to help me find the best solution...
>
> Have you found this web page ?http://irc.nrc-cnrc.gc.ca/pubs/cbd/cbd240_e.html

I didn't find it myself so thank you very much. Very good article...

dude-guy
September 29th 08, 02:24 PM
On 26 Sep., 15:09, "N:dlzc D:aol T:com \(dlzc\)" >
wrote:
> Dear dude-guy:
> > Are you completely sure mass is the only thing
> > to consider?
>
> Only thing, no. *The material's ability to dampen vibration (good
> for polymer, poor for glass), and mechanical isolation. *Triple

Yes, this is also what I thought...

Polymer = good at damping vibrations...
Glass = has higher density...

What should I choose? What is the optimal / the best, when there's
already 1 layer of glass (actually 2 thin layers, it's a thermo-
isolating window for cold winters)...

> paned glass is like a wall, for both sound and heat transfer
> (well...)
>
> > Does it matter whether it's high or low frequent
> > noise?
>
> The spacing between panes will decide whether it dampens /
> isolates or resonates / amplifies the noise.

How to find the best spacing for absorbing noise from church bells?

What would you recommend?

dude-guy
September 29th 08, 02:29 PM
On 27 Sep., 00:38, "Tony" > wrote:
> "Asbjørn" > wrote in message
>
> ...
> (sensible suggestions, but only in alt.sci.physics.acoustics)
>
> I've set this back to all the original groups in case the OP isn't reading
> alt.sci.physics.acoustics.

Thanks - I wasn't reading that group earlier...

GregS[_3_]
September 29th 08, 04:04 PM
In article >, (GregS) wrote:
>In article >,
> dude-guy > wrote:
>>Hi,
>>
>>I desperately need an opinion from someone with a good understanding
>>of materials or noise reduction in general.
>>
>>I live close to a church and the church bell makes extreme loud noise.
>>The noise is really loud, going through my windows. I want to put an
>>extra layer of window - obviously it should be transparent. Should
>>this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>>
>>Which transparent material reduces "church bell" sound waves the most?
>>I was told these guys make something that can reduce noise:
>>http://www.altuglas.com
>>
>>Which frequencies do I need to reduce (freq. of sound from church
>>bell)?
>>
>>How about optimal layer thickness of the transparent material?
>>
>>Hope somebody is clever enough to help me find the best solution...
>
>Do you now have a energy double panned window. Thats the first step.
>


This dude has not said what he has for windows, types, sizes, etc.

greg

Mark B
September 29th 08, 04:28 PM
On Sep 25, 11:31*am, dude-guy > wrote:
> Hi,
>
> I desperately need an opinion from someone with a good understanding
> of materials or noise reduction in general.
>
> I live close to a church and the church bell makes extreme loud noise.
> The noise is really loud, going through my windows. I want to put an
> extra layer of window - obviously it should be transparent. Should
> this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> Which transparent material reduces "church bell" sound waves the most?
> I was told these guys make something that can reduce noise:http://www.altuglas.com
>
> Which frequencies do I need to reduce (freq. of sound from church
> bell)?
>
> How about optimal layer thickness of the transparent material?
>
> Hope somebody is clever enough to help me find the best solution...

You should also make sure that the primary window is air tight. If
there are air leaks here they will let in much more noise. This
company makes a great product for sealing existing double hung
windows.

http://www.advancedrepair.com/weather_stripping/easy_stop.htm

M Bagdon

dlzc
September 29th 08, 06:50 PM
Dear dude-guy:

On Sep 29, 6:24*am, dude-guy > wrote:
> On 26 Sep., 15:09, "N:dlzcD:aol T:com \(dlzc\)" >
> wrote:
>
> > Dear dude-guy:
> > > Are you completely sure mass is the only thing
> > > to consider?
>
> > Only thing, no. *The material's ability to dampen
> > vibration (good for polymer, poor for glass), and
> > mechanical isolation. *Triple
>
> Yes, this is also what I thought...
>
> Polymer = good at damping vibrations...
> Glass = has higher density...
>
> What should I choose?

Both, if sandwiched.

> What is the optimal / the best, when there's
> already 1 layer of glass (actually 2 thin
> layers, it's a thermo-isolating window for cold
> winters)...
>
> > paned glass is like a wall, for both sound
> > and heat transfer
> > (well...)
>
> > > Does it matter whether it's high or low frequent
> > > noise?
>
> > The spacing between panes will decide whether
> > it dampens / isolates or resonates / amplifies
> > the noise.
>
> How to find the best spacing for absorbing noise
> from church bells?
>
> What would you recommend?

The mathematics on spacing will be similar to the length of an organ
pipe, only closed at both ends. 1 to 2 inches in length (separation)
will not respond well to the first few harmonics of the bell's tone.

Almost anything will be better than nothing.

David A. Smith

GregS[_3_]
September 29th 08, 07:23 PM
In article >, Mark B > wrote:
>On Sep 25, 11:31=A0am, dude-guy > wrote:
>> Hi,
>>
>> I desperately need an opinion from someone with a good understanding
>> of materials or noise reduction in general.
>>
>> I live close to a church and the church bell makes extreme loud noise.
>> The noise is really loud, going through my windows. I want to put an
>> extra layer of window - obviously it should be transparent. Should
>> this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>>
>> Which transparent material reduces "church bell" sound waves the most?
>> I was told these guys make something that can reduce noise:http://www.alt=
>uglas.com
>>
>> Which frequencies do I need to reduce (freq. of sound from church
>> bell)?
>>
>> How about optimal layer thickness of the transparent material?
>>
>> Hope somebody is clever enough to help me find the best solution...
>
>You should also make sure that the primary window is air tight. If
>there are air leaks here they will let in much more noise. This
>company makes a great product for sealing existing double hung
>windows.
>
>http://www.advancedrepair.com/weather_stripping/easy_stop.htm
>
>M Bagdon

My 58 year old house has some really good windows which I am now replacing with
energy efficient ones. For 58 years they still seal pretty well and all the hardware works.
The outer storm window was also a plus. The hard part is ripping out the old
and putting in the new. It takes me around 4 hours work each, and does not include
final trim. I notice on the new windows, there is a resonant range when a person outside
the window is speaking and I hear a kind of hollow sound on the other side. I have 9 windows
to replace and possible bay window. I imagine the resonance changes as the temperatur changes,
and the glass bows in different amounts.

greg

Tony[_3_]
September 30th 08, 10:31 AM
"GregS" > wrote in message
...

>... I notice on the new windows, there is a resonant range when a person
>outside
> the window is speaking and I hear a kind of hollow sound on the other
> side. I have 9 windows
> to replace and possible bay window. I imagine the resonance changes as the
> temperatur changes,
> and the glass bows in different amounts.

This might be the effect of sealed double glazing units (IGU). These have
two fairly thin layers of glass separated by a small air space, so there is
a resonance between the mass of the glass and the springiness of the air
between. The resonance frequency will probably be in the low hundreds of
Hz.

--
Tony W
My e-mail address has no hyphen
- but please don't use it, reply to the group.

Shhhh! I'm Listening to Reason!
September 30th 08, 10:44 AM
On Sep 25, 10:31*am, dude-guy > wrote:
> Hi,
>
> I desperately need an opinion from someone with a good understanding
> of materials or noise reduction in general.
>
> I live close to a church and the church bell makes extreme loud noise.
> The noise is really loud, going through my windows. I want to put an
> extra layer of window - obviously it should be transparent. Should
> this extra layer be real "window glass" or polymeric/plastic "PMMA"?

Check what the STC rating for the storm windows is. Here is a good
primer on noise reduction for reducing airport noise, which will
likely be overkill for church bells:

www.macnoise.com/pdfs/home-insulation-program/sound_mitigation_guide_final.pdf
-

> Which transparent material reduces "church bell" sound waves the most?

It relates to the STC rating, which measure sound transmission of
windows and doors in general. Glass can be fine if it is thick enough.
The higher the STC rating is, less sound is passed.

> I was told these guys make something that can reduce noise:http://www.altuglas.com
>
> Which frequencies do I need to reduce (freq. of sound from church
> bell)?
>
> How about optimal layer thickness of the transparent material?
>
> Hope somebody is clever enough to help me find the best solution...

Unfortunately homes also need airflow to function properly. If you
button everything up too tight, you'll end up with unhealthy interior
air and possibly moldy walls. You'll have to strike a balance between
airtight (meaning less sound is transmitted to the interior) and
interior air quality. If you close things too tight up you may need to
retrofit an air-to-air exchanger.

Shhhh! I'm Listening to Reason!
September 30th 08, 10:50 AM
On Sep 30, 4:44*am, "Shhhh! I'm Listening to Reason!"
> wrote:
> On Sep 25, 10:31*am, dude-guy > wrote:
>
> > Hi,
>
> > I desperately need an opinion from someone with a good understanding
> > of materials or noise reduction in general.
>
> > I live close to a church and the church bell makes extreme loud noise.
> > The noise is really loud, going through my windows. I want to put an
> > extra layer of window - obviously it should be transparent. Should
> > this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> Check what the STC rating for the storm windows is. Here is a good
> primer on noise reduction for reducing airport noise, which will
> likely be overkill for church bells:
>
> www.macnoise.com/pdfs/home-insulation-program/sound_mitigation_guide_...
> -
>
> > Which transparent material reduces "church bell" sound waves the most?
>
> It relates to the STC rating, which measure sound transmission of
> windows and doors in general. Glass can be fine if it is thick enough.
> The higher the STC rating is, less sound is passed.

I forgot to add: use a dissimilar thickness of glass (or other
material, but I'd personally probably just stay with glass) from your
prime glass for the storm windows to help reduce resonance.

dude-guy
September 30th 08, 03:41 PM
On 29 Sep., 19:50, dlzc > wrote:
> > > Only thing, no. *The material's ability to dampen
> > > vibration (good for polymer, poor for glass), and
> > > mechanical isolation. *Triple
>
> > Yes, this is also what I thought...
>
> > Polymer = good at damping vibrations...
> > Glass = has higher density...
>
> > What should I choose?
>
> Both, if sandwiched.

OMG... Now we're back again to the mass discussion. Is mass (real
glass, not polymers) the most important thing or is it the ability to
absorb noise (polymers, lower density)?

Some people say glass is the only thing to consider (double layer) and
now you say polymer (since there's already glass)... Is it strange I'm
confused?

> > What is the optimal / the best, when there's
> > already 1 layer of glass (actually 2 thin
> > layers, it's a thermo-isolating window for cold
> > winters)...
>
> > > paned glass is like a wall, for both sound
> > > and heat transfer
> > > (well...)
>
> > > > Does it matter whether it's high or low frequent
> > > > noise?
>
> > > The spacing between panes will decide whether
> > > it dampens / isolates or resonates / amplifies
> > > the noise.
>
> > How to find the best spacing for absorbing noise
> > from church bells?
>
> > What would you recommend?
>
> The mathematics on spacing will be similar to the length of an organ
> pipe, only closed at both ends. *1 to 2 inches in length (separation)
> will not respond well to the first few harmonics of the bell's tone.

I've probably seen something like that before, but how do you
calculate the harmonics?

Since this is posted to materials science and acoustics science
group(s), I hope somebody knows how to calculate it and can show the
equations for the rest of us?

> Almost anything will be better than nothing.

Yes, agreed and something must (and will) happen... I just want "the
best solution" and get to a good understanding of the important
variables to choose the solution from (before spending my money on
something that could later turn out to be more or less useless)...

dude-guy
September 30th 08, 04:47 PM
On 30 Sep., 11:44, "Shhhh! I'm Listening to Reason!"
> wrote:
> On Sep 25, 10:31*am, dude-guy > wrote:

> > Which transparent material reduces "church bell" sound waves the most?
>
> It relates to the STC rating, which measure sound transmission of
> windows and doors in general. Glass can be fine if it is thick enough.
> The higher the STC rating is, less sound is passed.

Thanks for introducing the term: "STC".

> > I was told these guys make something that can reduce noise:http://www.altuglas.com
>
> > Which frequencies do I need to reduce (freq. of sound from church
> > bell)?
>
> > How about optimal layer thickness of the transparent material?
>
> > Hope somebody is clever enough to help me find the best solution...
>
> Unfortunately homes also need airflow to function properly. If you
> button everything up too tight, you'll end up with unhealthy interior
> air and possibly moldy walls. You'll have to strike a balance between
> airtight (meaning less sound is transmitted to the interior) and
> interior air quality. If you close things too tight up you may need to
> retrofit an air-to-air exchanger.

Yes, I'm aware of the problem, thanks...

dlzc
September 30th 08, 05:03 PM
Dear dude-guy:

On Sep 30, 7:41*am, dude-guy > wrote:
> On 29 Sep., > wrote:
....
> > > Yes, this is also what I thought...
>
> > > Polymer = good at damping vibrations...
> > > Glass = has higher density...
>
> > > What should I choose?
>
> > Both, if sandwiched.
>
> OMG... Now we're back again to the mass
> discussion. Is mass (real glass, not
> polymers) the most important thing or is it
> the ability to absorb noise (polymers, lower
> density)?

What makes you think there is only one "most important thing"? You or
others have said they can hear voices outside their mulitply-glazed
windows near resonant frequencies. Dampening, such as provided by a
polymer substrate, can reduce even that noise.

> Some people say glass is the only thing to
> consider (double layer) and now you say
> polymer (since there's already glass)... Is it
> strange I'm confused?

Yes. Read the word "sandwich" above. Glass for mass, polymer for
dampening.

As to mathematics:
http://hyperphysics.phy-astr.gsu.edu/hbase/class/phscilab/restube2.html
.... and just adjust the lengths arrived at by 2/3, since this is based
on one end open. But until you know the bell's tone / frequency
range...

....
> > Almost anything will be better than nothing.
>
> Yes, agreed and something must (and will)
> happen... I just want "the best solution" and
> get to a good understanding of the important
> variables to choose the solution from (before
> spending my money on something that
> could later turn out to be more or less
> useless)...

Anything you do, even "non-optimal" but still recommended on this
group, will be a noticeable improvement.

David A. Smith

Angelo Campanella
October 5th 08, 03:18 PM
Don Pearce wrote:

> Angelo Campanella wrote:
>> Above 69 Hz, the sound attenuation (insertion loss) increases rapidly
>> with frequency.
>> There are various theoretical "estimates" of such attenuation, but
>> the only way to really determine it to build one and try it. My
>> experience for such a window (I have specified and tested one such for
>> an audio control room window at Ball State University
>> Telecommnications learning center in late 1980's. I tested it as about
>> FSTC 54.
> Angelo, have you ever tried this with the glass panes forced into a
> slight curve by the frame? Stiffness against an incident acoustic wave
> is increased considerably.

That is an interesting hypothesis. That stiffness will interact with
two phenomena:

1- The higher bending stiffness in one direction will raise the
coincidence frequency above the 2500 Hz resonance "achilles heel" of
window glass. The other direction will still demonstrate coincidence
transmission around 2500 Hz, I think.

2- The panel resonance of 69 Hz may or not be affected because that
resonance is by the panel alone. It is more significant that stiffness
offered by the frame will interact with a flat pane. More clamping
stiffness will *raise* the resonance frequency above 69 Hz (as will also
the curved panel surface), placing it again back in the middle audio
range, which we do NOT want to do. It is best that the glass pane be
held by limp (soft rubber) supports at its edge and be flat, I think.
Again, this is all speculation. One has to build it and try it.

Similarly, I do not use tilted glass panes for audio control windows
despite their "sexy" appearance for two reasons.

1- The effectiveness in noise isolation strongly depends on the minimum
spacing rather than the maximum spacing in that wedged space. Hence, if
one wants maximum sound attenuation, one spaces the glass surfaces as
far apart as possible.

[The absolute best sound attenuation will occur for an interior window
when you simply cut a hole of any size or shape clear through that wall.
Leave the stud cavity OPEN to the window gap. Set fiberglass in the stud
gap within the wall. Spray paint it black if you don't like to see pink
or yellow there. (The one and only application of Sonex I have ever
recommended has been as an ersatz black cover for this gap. It is in the
studio windows at Ball State Communications Complex.) DON'T cover that
gap with a flat plate of any sort, as this will trap sound in the window
gap and deteriorate the sound attenuation. (Ugly but good follows:) Cut
two sheets of plate glass oversize to cover the window hole plus a 2" to
4" margin all around. Either RTV the glass to the wall all around, or
build a picture frame of wood to secure it if you don't like that much
ugly. Caulk the entire glass edge perimeter before laying that frame.
Treat the other side of the wall exactly the same way. This window will
have HIGHER sound attenuation than the surrounding wall.]

2- Titled panes always produce new reflections of ceiling and perimeter
lights and lit objects than is normally experienced. This can be very
annoying for everyday use.

Cheers,

Angelo Campanella

Tony[_3_]
October 5th 08, 11:12 PM
Angelo Campanella wrote:
> 1- The effectiveness in noise isolation strongly depends on the minimum
> spacing rather than the maximum spacing in that wedged space. Hence, if
> one wants maximum sound attenuation, one spaces the glass surfaces as
> far apart as possible.

What's the theoretical basis for that Angelo? I have always assumed it was
the average spacing that mattered.

I agree that tilting panes is not effective for improving isolation and is
often counter-productive for reducing light reflections, but it is sometimes
necessary in a low RT room for stopping a flutter echo. Of course, in
practice increasing the average spacing and increasing the minimum spacing
will often come to the same thing because one will optimise performance for
an overall window thickness by making the panes parallel. But on the
occasions when a tilted pane is required for whatever reason, your
philosophy will lead to a bigger spacing, or the need for thicker glass for
the same spacing, than mine.

--
Tony W
My e-mail address has no hyphen
- but please don't use it, reply to the group.

Angelo Campanella
October 11th 08, 06:03 PM
Tony wrote:
> Angelo Campanella wrote:
>
>>1- The effectiveness in noise isolation strongly depends on the minimum
>>spacing rather than the maximum spacing in that wedged space. Hence, if
>>one wants maximum sound attenuation, one spaces the glass surfaces as
>>far apart as possible.
>
>
> What's the theoretical basis for that Angelo?
> I have always assumed it was
> the average spacing that mattered.

Consider a window split down the middle or two windows side by side.
One half has a TL of 50 dB, the other half has a TL of 40 dB. What is
the resulting average TL? It would be 43 dB, closer to the 40 dB half
that to the 50 dB half. The definition of "Average" matters. If you
simply average numerals, you get 45 dB.

You might average sound power expressed in watts. Maybe one-half
picowatt goes through the 50 dB part, while 5 picowatts goes through the
40 dB part, the sum being 5.5 picowatts, nearer the 40 dB window part
than to the 50 dB window part.

> I agree that tilting panes is not effective for improving isolation and is
> often counter-productive for reducing light reflections, but it is sometimes
> necessary in a low RT room for stopping a flutter echo.

I am only addressing sound transmission. Introducing flutter echoes is
a problem of a third kind. To effectively reduce flutter echoes, tilt
the whole wall. If that's not feasible (e.g. an existing room in an
existing building), then the choice becomes which side pane is more
readily tilted outward. Top? Bottom? Room lamp locations must be
considered. Think it out. That's what you are paid to do. Pane-tilting
on either the vertical or horizontal axis will suit for reducing flutter
echoes.

> Of course, in
> practice increasing the average spacing and increasing the minimum spacing
> will often come to the same thing because one will optimise performance for
> an overall window thickness by making the panes parallel. But on the
> occasions when a tilted pane is required for whatever reason, your
> philosophy will lead to a bigger spacing, or the need for thicker glass for
> the same spacing, than mine.

The designer is obliged to pick a method and to defend that choice in
any way they please. I am only addressing accurately the sound isolation
feature of a window.

Ang. C.

GregS[_3_]
October 14th 08, 02:06 PM
In article >, wrote:
>
>
>Tony wrote:
>> Angelo Campanella wrote:
>>
>>>1- The effectiveness in noise isolation strongly depends on the minimum
>>>spacing rather than the maximum spacing in that wedged space. Hence, if
>>>one wants maximum sound attenuation, one spaces the glass surfaces as
>>>far apart as possible.
>>
>>
>> What's the theoretical basis for that Angelo?
>> I have always assumed it was
>> the average spacing that mattered.
>
> Consider a window split down the middle or two windows side by side.
>One half has a TL of 50 dB, the other half has a TL of 40 dB. What is
>the resulting average TL? It would be 43 dB, closer to the 40 dB half
>that to the 50 dB half. The definition of "Average" matters. If you
>simply average numerals, you get 45 dB.
>
> You might average sound power expressed in watts. Maybe one-half
>picowatt goes through the 50 dB part, while 5 picowatts goes through the
>40 dB part, the sum being 5.5 picowatts, nearer the 40 dB window part
>than to the 50 dB window part.
>
>> I agree that tilting panes is not effective for improving isolation and is
>> often counter-productive for reducing light reflections, but it is sometimes
>> necessary in a low RT room for stopping a flutter echo.
>
> I am only addressing sound transmission. Introducing flutter echoes is
>a problem of a third kind. To effectively reduce flutter echoes, tilt
>the whole wall. If that's not feasible (e.g. an existing room in an
>existing building), then the choice becomes which side pane is more
>readily tilted outward. Top? Bottom? Room lamp locations must be
>considered. Think it out. That's what you are paid to do. Pane-tilting
>on either the vertical or horizontal axis will suit for reducing flutter
>echoes.
>
>> Of course, in
>> practice increasing the average spacing and increasing the minimum spacing
>> will often come to the same thing because one will optimise performance for
>> an overall window thickness by making the panes parallel. But on the
>> occasions when a tilted pane is required for whatever reason, your
>> philosophy will lead to a bigger spacing, or the need for thicker glass for
>> the same spacing, than mine.
>
> The designer is obliged to pick a method and to defend that choice in
>any way they please. I am only addressing accurately the sound isolation
>feature of a window.
>

I am curious about the effect of Argon. I suppose it would be slightly better
at reducing sound level.

greg

Shhhh! I'm Listening to Reason!
October 14th 08, 08:03 PM
On Oct 14, 8:06*am, (GregS) wrote:
> In article >, wrote:
>
> >Tony wrote:
> >> Angelo Campanella wrote:
>
> >>>1- The effectiveness in noise isolation strongly depends on the minimum
> >>>spacing rather than the maximum spacing in that wedged space. Hence, if
> >>>one wants maximum sound attenuation, one spaces the glass surfaces as
> >>>far apart as possible.
>
> >> What's the theoretical basis for that Angelo? *
> >> I have always assumed it was
> >> the average spacing that mattered.
>
> > * * * *Consider a window split down the middle or two windows side by side.
> >One half has a TL of 50 dB, the other half has a TL of 40 dB. What is
> >the resulting average TL? * It would be 43 dB, closer to the 40 dB half
> >that to the 50 dB half. The definition of "Average" matters. If you
> >simply average numerals, you get 45 dB.
>
> > * * * *You might average sound power expressed in watts. Maybe one-half
> >picowatt goes through the 50 dB part, while 5 picowatts goes through the
> >40 dB part, the sum being 5.5 picowatts, nearer the 40 dB window part
> >than to the 50 dB window part.
>
> >> I agree that tilting panes is not effective for improving isolation and is
> >> often counter-productive for reducing light reflections, but it is sometimes
> >> necessary in a low RT room for stopping a flutter echo.
>
> > * * * *I am only addressing sound transmission. Introducing flutter echoes is
> >a problem of a third kind. To effectively reduce flutter echoes, tilt
> >the whole wall. If that's not feasible (e.g. an existing room in an
> >existing building), then the choice becomes which side pane is more
> >readily tilted outward. Top? Bottom? Room lamp locations must be
> >considered. Think it out. That's what you are paid to do. Pane-tilting
> >on either the vertical or horizontal axis will suit for reducing flutter
> >echoes.
>
> >> Of course, in
> >> practice increasing the average spacing and increasing the minimum spacing
> >> will often come to the same thing because one will optimise performance for
> >> an overall window thickness by making the panes parallel. *But on the
> >> occasions when a tilted pane is required for whatever reason, your
> >> philosophy will lead to a bigger spacing, or the need for thicker glass for
> >> the same spacing, than mine.
>
> > * * * *The designer is obliged to pick a method and to defend that choice in
> >any way they please. I am only addressing accurately the sound isolation
> >feature of a window.
>
> I am curious about the effect of Argon. I suppose it would be slightly better
> at reducing sound level.

Argon is heavier (more dense) than air. I would expect it generally to
transmit sound more efficiently as a result, but I doubt that it would
be really significant either way.

Here is something I found in a quick search. Argon or other inert
filler gases are not mentioned:

http://www.donyoungwindows.com/faq/sound.asp

This seems to support my assumption:

The use of argon gas fill in IG units improves sound transmission loss
characteristics at higher frequencies, but air-filled units have an
advantage at the lower frequencies associated with traffic noise.
Therefore, OITC is actually better without argon. Again, the tradeoff
with energy-saving goals must be balanced.

http://www.cbpmagazine.com/article.php?articleid=252

Angelo Campanella
October 18th 08, 07:08 AM
GregS wrote:
> I am curious about the effect of Argon. I suppose it would be slightly better
> at reducing sound level.

I's a double-edged sword. The density is greater so its acoustic
impedance is greater, but not neary as great as glass. I think the chief
advantage is a slower sound speed, making the frequency a which the
cavity is resonant much lower. Then there is that exotic coincidence
effect. for that, it looks good since the inner (argon) and outer (air)
coincidence frequencies differ, being, I think the major, and only
significant effect. The low frequency difference mentioned by Zekfr is
harder to fathom.

Angelo Campanella

Asbjørn
October 18th 08, 06:09 PM
"Angelo Campanella" > wrote in message
...
> GregS wrote:
>> I am curious about the effect of Argon. I suppose it would be slightly
>> better
>> at reducing sound level.
>
> I's a double-edged sword. The density is greater so its acoustic impedance
> is greater, but not neary as great as glass. I think the chief advantage
> is a slower sound speed, making the frequency a which the cavity is
> resonant much lower. Then there is that exotic coincidence effect. for
> that, it looks good since the inner (argon) and outer (air) coincidence
> frequencies differ, being, I think the major, and only significant effect.
> The low frequency difference mentioned by Zekfr is harder to fathom.
>
> Angelo Campanella
>

Argon and some other pure gas fillings in double glazing usually give a
little better insulation in a wide middle frequency range but a little less
insulation at low and high frequencies. It may help against churchbells but
it may be bad for noise from heavy traffic, Harleys and bass intensive
music. An Argon SF6 mix is better for noise insulation but not good for the
rest of the environment.

Asbjørn.
(Switching to news.motzarella.org seems to have solved my previous
newsreader problem.)

Angelo[_3_]
December 16th 08, 12:20 PM
Difficult to achieve, but double glass filled with water, will isolate the
sound. But then you still have other entrances of noise -walls, slots,
cokeer-hood, reflections from buildings near you...


? "Angelo Campanella" > ?????? ??? ??????
...
> dude-guy wrote:
>> I live close to a church and the church bell makes extreme loud noise.
>> The noise is really loud, going through my windows. I want to put an
>> extra layer of window - obviously it should be transparent. Should
>> this extra layer be real "window glass" or polymeric/plastic "PMMA"?
>
> Do NOT waste money on plastic products, as the mass (weight) is the only
> sound reducing entity that will help, and glass is cheaper by the pound.
>
>> Which transparent material reduces "church bell" sound waves the most?
>> I was told these guys make something that can reduce noise:
>> http://www.altuglas.com
>
> Simply add thick glass "storm windows to the windows facing the bell
> tower, and on windows on facades that are at right angles to same.
>
>> Which frequencies do I need to reduce (freq. of sound from church
>> bell)?
>
> The bell tones, likely above about 200 Hz, but that varies with size.
>
> There is another aspect: Recently, pastors have become enamored with
> electric bell chimes. Some believe they do the community a favor by
> operating them loudly and frequently. Determine whether this is the case
> for your location. If so, then register a complaint to the church
> administration, that their chime operation is annoying to the residents.
> Perhaps they could reduce it a a single daily Angelus at noon or 6pm.
>
> Angelo Campanella
>