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View Full Version : Help! Can outdoor speakers be muffled?



TravelGal
01-27-17, 03:04 PM
For the last several years, we've been battling with the high school across the street. Since they installed a new system, their announcements and, worse, their "tones" blast us out of our seats, even while we're in the house. These tones shriek at least 20 times a day, often in bursts of 3.

After writing to everyone in the known world of LA Unified School district, we now have the principal's attention. He had his maintenance man put a plastic cover over the speaker that is directly facing our house. It is on the top of a second story about 400 feet away. (The intervening space is flat playing fields.) That action actually made the tones sound louder.

My question is: is there any sort of material they can use that might be sound absorbent? Or, would a reflector turn the sound toward the playing field areas rather than across the fields to us? They say the system has no volume control. They are not allowed to turn it off. They cannot disconnect even one speaker. They suggested facing the speakers down but they didn't do it. Maybe the mountings wouldn't allow that. Obviously, I can't see that detail from this distance.

Second question re: sound waves. Is it possible that it is louder here than it is at the school? They say it louder there because they are closer but I wonder if it is because the speakers are pointed toward us. I don't see how they could function if it's louder there.

Any help from the resident scientists would be appreciated.

SteveH
01-27-17, 03:41 PM
I'll bet your community has a noise ordinance. If these sounds are above those limits then it's not up to you to tell them how to fix the issue, they will need to determine a resolution if you file a complaint. A cheap sound meter on Amazon is under $20 BAFX Products® - Decibel Meter / Sound Level Reader - W/ ! https://www.amazon.com/dp/B00ECCZWWI/ref=cm_sw_r_cp_tai_Ji6Iyb68SJFG2

Gnam
01-27-17, 03:47 PM
https://s30.postimg.org/vhaw0jor5/prod_1433596114_src_http_cdn0_grizzly_com_pics.jpg

Gnam
01-27-17, 04:10 PM
You'll need to wrap the speaker with something like a teapot cozy. Thick, soft material that can't transmit the vibrations to the surrounding air. To weather proof it, you'll need to wrap it with plastic and maintain it over the years.

They sell freeze protection pouches for above ground piping. Depending on the size of the speaker, that might work.
https://s28.postimg.org/ggkcq766l/602_GN_2_T.jpg

The other option is to retaliate. Blast your own music at the same decibel level and see how they like it. ;)

Insomniac
01-27-17, 04:41 PM
Sound waves are directional and it's impossible for them to be louder the further you are away (assuming no amplification on its way). It may seem louder than where they are standing because of the direction the speakers are pointed (the sound is likely going over the grounds instead of towards them. It's hard to muffle sound without distorting it, which would then just make it harder to understand. They should be working on redirecting or repositioning the speaker. Second, they can lower the volume quite easily with a resistor(s). It will drop the voltage to the speaker.

WickerBill
01-27-17, 05:28 PM
"They are not allowed to turn it off. They cannot disconnect even one speaker."

You need to ask them who is setting these restrictions, and then when that person or agency is named, go directly to them.



And it is highly unlikely there is no volume control. Even in 70v or 100v systems, where there is no output control on most speakers, there are different wattage taps to wire in each speaker, and an overall volume control on the amplifier.

G.
01-27-17, 09:06 PM
https://s30.postimg.org/vhaw0jor5/prod_1433596114_src_http_cdn0_grizzly_com_pics.jpg

921

TravelGal
01-27-17, 09:27 PM
Thanks, all. Steve, the sounds, as brilliant as they are, fall within the noise control limits because they are during the day. Pretty much anything goes. Insomniac, dang. Maybe it's not louder but is certainly more piercing when the sound waves head straight to your eardrums.

WB, the panel, known as the LAUSD sets the rules for the schools. If you think city politics is bad, you ain't seen nothing yet until you delve into a $7.8 billion school district. School swears there is no volume control. Never uttered the word "amplifier." Where would the wattage taps be? Right at the speaker mounting?

The principal "has the alarm company come out" but now that I know to throw the words "resistor" and "wattage taps" at them, I might get somewhere. I think I"ll also ask for the name of the company and exactly name of the alarm system. I think it is all just laziness on their part.

If all else fails, I'll go to Cost Plus and get those tea cozies.

G., I'm particularly partial to your addition. Those clippers from Gnam would require more climbing than I want to do in this wind. ;)

Before I close, I'd like to add that I am not the only one complaining. I'm just the one that decided is has to get fixed or ELSE.

Thanks again, guys. :D

WickerBill
01-27-17, 10:20 PM
Here is a super simplistic 70 volt system transformer. You simply tie in to the wire that corresponds to the wattage (output) you want the speaker to have. Your situation, of course, will be higher tech and, if it is a 70 volt or 100 volt system, will have choices like 20w, 40w, 80w, 140w. :)

http://i.ebayimg.com/00/s/NDU1WDUwMA==/z/MGsAAOxyOMdS-oP6/$_3.JPG

datachicane
01-28-17, 01:12 AM
https://taynabatteri.es/img/articles/cherry-picker/cherry-picker.jpg
http://img.trailersailor.com/37629/2014/139796510744.jpg

Use a couple of cans, since you don't want to have to rent the cherry picker again.

TravelGal
01-28-17, 05:07 PM
Use a couple of cans, since you don't want to have to rent the cherry picker again.

As I read through the description of what that stuff does, I found a guy who said to use it all in one whack because you couldn't close the can effectively and that, fortunately, he had an old house so he used it up. I immediately missed Oddlycalm. Thanks for the memory. And the suggestion. I'll be needing stronger cutters than Gnam suggested to get through the chain link fence around the school hard but it might be worth it.

Insomniac
01-28-17, 08:07 PM
Insomniac, dang. Maybe it's not louder but is certainly more piercing when the sound waves head straight to your eardrums.

If you stood next to the speaker (not below it) it would be so much worse. ;) I think instead of resistor you could just mention a potentiometer (it's effectively a variable resistor in this use case, but any sound engineer knows the term "pot up/down" and their use).

G.
01-28-17, 08:14 PM
If you stood next to the speaker (not below it) it would be so much worse. ;) I think instead of resistor you could just mention a potentiometer (it's effectively a variable resistor in this use case, but any sound engineer knows the term "pot up/down" and their use).

(not being a smartass)

poe-TEN-she-omm-it-ter

datachicane
01-28-17, 08:28 PM
Yep, no second use with a sprayfoam can.

Heck, better yet, buy a cheap telescoping painter's pole, duct tape the can to the top, put a zip tie around the trigger (wear old clothes, a hat, and safety goggles), and do it from the ground, no cherry picker necessary. If I lived closer I'd do it just for kicks. :cool:

Gnam
01-30-17, 01:32 PM
Sabotage is only a temporary fix. A long term solution would be to make the school want to take the speakers down. Right now, the school likes the speakers because they control when they go off and what sound they make. If the speakers made unwanted noise, like static, at an inopportune time, like during class, the school would rip the speakers down for you. ;)

datachicane
01-30-17, 02:43 PM
Heh, that brings back memories.
Back when I was in High School in the late '70s, I built a homemade motorcycle-battery-power-amp-and-car-deck-in-a-briefcase boombox, spliced it into an outside school PA speaker, hid it in the bushes, and played Jimi Hendrix throughout the school for most of the day until the battery gave out. I'd probably got the impedance wrong, since it was distorted and crappy, but it still got the desired results. :tony:

Young data on the left:

https://lh3.googleusercontent.com/AJokzkdBStcAGLeoLi-WRjl0FOhczTbYxhabCkmM9pzEh-nhfjanBgC8ruqnSAn-svoa8GgvmrxrHg=w1920-h1080-no

TravelGal
01-30-17, 03:50 PM
Heck, better yet, buy a cheap telescoping painter's pole, duct tape the can to the top, put a zip tie around the trigger (wear old clothes, a hat, and safety goggles), and do it from the ground, no cherry picker necessary. If I lived closer I'd do it just for kicks. :cool:

I like this. The hole in the fence would be so much smaller.


Sabotage is only a temporary fix. A long term solution would be to make the school want to take the speakers down. Right now, the school likes the speakers because they control when they go off and what sound they make. If the speakers made unwanted noise, like static, at an inopportune time, like during class, the school would rip the speakers down for you. ;)

Would you like to come down here and demonstrate? I'm all ears.

rabbit
01-30-17, 04:28 PM
I'm all ears.
Maybe that's why it seems so loud... :gomer: :p

Insomniac
01-30-17, 04:55 PM
Why is a fence an impediment? Just jump it. :D (It's not topped with razor wire, right?)

WickerBill
01-31-17, 08:43 AM
Maybe that's why it seems so loud... :gomer: :p

*golf clap*

TravelGal
02-01-17, 12:56 PM
(I'm all ears) Maybe that's why it seems so loud... :gomer: :p


*golf clap*

I love it when you get the joke. Bwhhaahaaa.


Why is a fence an impediment? Just jump it. :D (It's not topped with razor wire, right?)

Thanks for the compliment. Insomniac. This reminded me of years ago when I met someone from 7G at a race and he kept saying, YOU'RE TRAVELGAL? Yes, not all gals are 19 years old and fit enough to leap tall buildings in a single bound. :laugh::laugh:

Gnam
02-01-17, 08:01 PM
Let's approach the issue from another direction. How do you feel about domes?

https://s24.postimg.org/o292e1lyd/IMG_9397.jpg

Kiwifan
02-02-17, 01:03 AM
I love it when you get the joke. Bwhhaahaaa.



Thanks for the compliment. Insomniac. This reminded me of years ago when I met someone from 7G at a race and he kept saying, YOU'RE TRAVELGAL? Yes, not all gals are 19 years old and fit enough to leap tall buildings in a single bound. :laugh::laugh:

Can't leap over tall buildings eh? I heard you leapt head over heals for TravelGuy. :D

Good luck with the noise. To bring it back to a Champ Car theme I remember when someone thought it would be a great idea to set up a bar with HUGE speakers (and crap music) right opposite our stand on the Goldy. You remember the sound of a Champ Car? Couldn't hear them over the music. Sigh. Our stand of over 300 complained so they reluctantly agreed to only play the music when the cars weren't on track. They were pis!*d as they had paid good money to be there. We argued that WE had paid good money to be there and it WAS a motor racing event and not a concert.

Hope you get it sorted Gal.

TravelGal
02-02-17, 07:18 PM
Let's approach the issue from another direction. How do you feel about domes?

https://s24.postimg.org/o292e1lyd/IMG_9397.jpg

I would LOVE it. I wonder who I can approach to build one for us as an experiment to measure.............something. I'm putting on my thinking cap, which looks suspiciously like that dome. :gomer:

datachicane
02-02-17, 09:44 PM
Nice, 6v geodesic. :thumbup:
I was the geek in college building huge ones out of everything from drinking straws to PVC. Even built an RC airship once with a geodesic prolate spheroid exoskeleton, that was fun.

WickerBill
02-03-17, 09:18 AM
Nice, 6v geodesic. :thumbup:
.

I'm buying this one when I'm able.

https://secure.parksandresorts.wdpromedia.com/resize/mwImage/1/630/354/75/wdpromedia.disney.go.com/media/wdpro-assets/parks-and-tickets/attractions/epcot/spaceship-earth/spaceship-earth-00.jpg?17072014154116

datachicane
02-03-17, 06:40 PM
I'm buying this one when I'm able.

https://secure.parksandresorts.wdpromedia.com/resize/mwImage/1/630/354/75/wdpromedia.disney.go.com/media/wdpro-assets/parks-and-tickets/attractions/epcot/spaceship-earth/spaceship-earth-00.jpg?17072014154116

Criminy, that thing's gotta be, what, 14 or 16v? Anybody know?

dando
02-03-17, 07:17 PM
Criminy, that thing's gotta be, what, 14 or 16v? Anybody know?


220/221...whatever it takes. ;) #Mr. Mom


https://www.youtube.com/watch?v=iX3kxAA2L4Q

BTW, Di$ney had MIT do some engineering studies for the 'golf ball' as it's called by some. Keep in mind it houses a full ride-through attraction. Considering how much $$$$$ I've spent there, I should already own it. :saywhat: :irked: :gomer: