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School Band Rehearsal Room Treatment

iMickey503

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The one think the U.K has done right is Acoustic in their schools. They even have a full guideline on this topic called the BB93 Acoustic design of schools and standards.

Something like this would be the best cost per Attenuation in the room with ease of installation. But there are rules to Modifying a Public school building in the united states.
pet-baffle-lg-1024x683.jpg

(Image courtesy of Sound Zero UK)



So... There are ways around it. You can hang up "Art Work".
1658527252940.png

(Image courtesy of Sound Zero UK)



This is the cheapest / Easy method for the room. The only other thing you need is fishing line.

1658527974574.png



Place them similar to this on walls.
Hero-Dale-Saylor-Joe-Williamson-NYC-Apartment-Michael-Muller-Remodelista.jpg


Hang these with fishing line from one side of the room to the other from the walls between the fluorescent tube light fixtures so they don't block the light. This will handle the sound projected upwards and do a fair amount of attenuation in the room for the least amount of cost that still looks like art in a room.


The walls as you said are concrete. Installing carpet pad on the walls is going to be a challenge due to what I mentioned above. The best bet is to decorate the walls with terry cloth. The school's order Rolls of this out of the janitorial budget fund You won't be misusing the funds as you have not used it. You just "Stored it" in the Music room. And its already approved for purchase as a general consumable.


Use Cardboard as the school has tons of that and its free, stamped with lots of holes with a Pizza hole puncher to make it fast and easy.
This helps make the cardboard better at absorbing sound waves.
61i7PQlmyQL._AC_SL1001_.jpg



Have the art kids take the cardboard, and cut it into strips on the paper guillotine in a 12x12 square being the final result.
1658534231306.png


The side of the corrugation is surprisingly effective at absorbing sound. Have them bevel them at different heights in order to look artistic while increasing the The noise reduction coefficient. Painting them different colors will help with aesthetics.
closeup-of-a-pile-of-corrugated-cardboard-picture-id1224749283





This may be silly, but it works. Music stands contribute to a lot of Reflections that are often unwanted. Use (Clean new) Mop heads from the Janitor closet and attach them over the wide area of the back of the metal stand. This will take care of floor reflections. Do the same for underneath the chairs.
9026f3d2c1d286d8279be040712340e6--mop-heads-glass-photography.jpg



Total out of pocket cost should be less then $300.
 

sarumbear

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The one think the U.K has done right is Acoustic in their schools. They even have a full guideline on this topic called the BB93 Acoustic design of schools and standards.

Something like this would be the best cost per Attenuation in the room with ease of installation. But there are rules to Modifying a Public school building in the united states.
pet-baffle-lg-1024x683.jpg

(Image courtesy of Sound Zero UK)



So... There are ways around it. You can hang up "Art Work".
View attachment 219832
(Image courtesy of Sound Zero UK)



This is the cheapest / Easy method for the room. The only other thing you need is fishing line.

View attachment 219833


Place them similar to this on walls.
Hero-Dale-Saylor-Joe-Williamson-NYC-Apartment-Michael-Muller-Remodelista.jpg


Hang these with fishing line from one side of the room to the other from the walls between the fluorescent tube light fixtures so they don't block the light. This will handle the sound projected upwards and do a fair amount of attenuation in the room for the least amount of cost that still looks like art in a room.


The walls as you said are concrete. Installing carpet pad on the walls is going to be a challenge due to what I mentioned above. The best bet is to decorate the walls with terry cloth. The school's order Rolls of this out of the janitorial budget fund You won't be misusing the funds as you have not used it. You just "Stored it" in the Music room. And its already approved for purchase as a general consumable.


Use Cardboard as the school has tons of that and its free, stamped with lots of holes with a Pizza hole puncher to make it fast and easy.
This helps make the cardboard better at absorbing sound waves.
61i7PQlmyQL._AC_SL1001_.jpg



Have the art kids take the cardboard, and cut it into strips on the paper guillotine in a 12x12 square being the final result.
View attachment 219839

The side of the corrugation is surprisingly effective at absorbing sound. Have them bevel them at different heights in order to look artistic while increasing the The noise reduction coefficient. Painting them different colors will help with aesthetics.
closeup-of-a-pile-of-corrugated-cardboard-picture-id1224749283





This may be silly, but it works. Music stands contribute to a lot of Reflections that are often unwanted. Use (Clean new) Mop heads from the Janitor closet and attach them over the wide area of the back of the metal stand. This will take care of floor reflections. Do the same for underneath the chairs.
9026f3d2c1d286d8279be040712340e6--mop-heads-glass-photography.jpg



Total out of pocket cost should be less then $300.
The problem with your suggestions are they are absorbers and as absorbers don’t work well at lower frequencies you have the risk of ending with a bad sounding room. The top image you posted show diffusers, not absorbers. Similar to what I suggested. But you are right, acoustics is an important part of architecture in the UK.

Almost always the best way to tame a problematic acoustic space is to use diffusers. Absorbers are used to eliminate specific echoes. They are not suitable for reducing the RT60 wide band.
 
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sam_adams

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A combination of diffusion and absorption could be employed along the lines of the work by the late Bogic Petrovic. There are some examples of his designs here and here. If your school district is large enough to have a central maintenance department, they may be able to construct these diffsorbers in house which might lower the cost to the school. They would also be familiar with local and state regulations regarding construction safety and proper materials use in school sites.
 

dasdoing

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Most of the reading I've done so far (on this forum and other places) is mainly focused in the theater and listening room realms, and I'm just not sure if those guidelines are a good starting point for us

No. the goals are diferent. there is a reason that recording studios have seperated recording and control rooms.
since this is not a recording room and budget is probably limited I would just foucus on bringing the annoyence down; means reverbaration.
you can simply start to add absorbtion panels to the middle of the 4 walls, listen to the result and if not satisfied add more.
just make sure to spread out the panels like so (but don't use foam)
rehearsalrooms05-iZhaZjOodYDHslouxyXBSxr7TNNzbI0u.jpg
 

sarumbear

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No. the goals are diferent. there is a reason that recording studios have seperated recording and control rooms.
since this is not a recording room and budget is probably limited I would just foucus on bringing the annoyence down; means reverbaration.
you can simply start to add absorbtion panels to the middle of the 4 walls, listen to the result and if not satisfied add more.
just make sure to spread out the panels like so (but don't use foam)
rehearsalrooms05-iZhaZjOodYDHslouxyXBSxr7TNNzbI0u.jpg
If you use a panel like that you will reduce the RT60 above 400Hz dramatically but the room will start to sound bass heavy the more panels you add. Almost all panels sold on the market works for human voice range. They are not suitable for large bandwidth music sources. For a band rehearsal room using absorption panels are a bad idea. Here is the absorption graph of a famous 2-inch panel. You can see that it will skew the sound dramatically below 200Hz and the result is a very odd sounding room that musicians will hate.


1658665733424.png
 

theREALdotnet

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If you use a panel like that you will reduce the RT60 above 400Hz dramatically but the room will start to sound bass heavy the more panels you add.

If that. A sporadic application of sheets like that will perhaps tame a slap echo, but not much else.

In my experience, a room like this needs thick floor-to-ceiling (2400mmx1200mmx200mm) high density polyester panels, straddling at least two corners of the room. This will make bass much more listenable, while at the same time making the room dryer. If it ends up too dry (unlikely with just two panels) then the panels can be partly covered with strips of tape, foil, wood or whatever, which won’t affect their bass absorption properties.
 

dasdoing

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If you use a panel like that you will reduce the RT60 above 400Hz dramatically but the room will start to sound bass heavy the more panels you add. Almost all panels sold on the market works for human voice range. They are not suitable for large bandwidth music sources. For a band rehearsal room using absorption panels are a bad idea. Here is the absorption graph of a famous 2-inch panel. You can see that it will skew the sound dramatically below 200Hz and the result is a very odd sounding room that musicians will hate.


View attachment 220163

well, we are talking about a rehearsal room here; not a recording room. the room should be big enough to not sound boomy. however if it does, some material in the corners will help. But I just don't think it will be necessary for the purpose.
also why use decrative panels? he should DIY some panels with mineral wool. will make a nice school project for the students, too.
on a sidenote: those values on the graph are messured flush on the floor in a reverberant room. with a little gap and more narrow sound wave angles incidences it will actualy look better.
 

sarumbear

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…why use decrative panels? he should DIY some panels with mineral wool. will make a nice school project for the students, too.
on a sidenote: those values on the graph are messured flush on the floor in a reverberant room. with a little gap and more narrow sound wave angles incidences it will actualy look better.
Decorative or not, all panels use the same structure hence have a similar response.

The OP said that the room is already small, hanging large panels away from the walls is not doable. Why suggest them? Besides, if panels will be mounted away from the wall why not use a thinner absorber? Absorber panel data is readily available. No need to suggest something without supporting data.

The only logical option on this case is to reduce the reflection from the ceiling by hanging diffusers. Players will absorb & diffuse the sound from the floor and you are left with only the walls. Once the diffusers are in place any slap echoes can then be located and treated with the mentioned absorbers. Slap echo frequency will be above 300Hz or so hence the 2in panels will be efficient enough.

Diffusion should always be the first action to tame a reverberant space. This is why concert halls are treated with diffusion. Only a few absorbers used to reduce slap echoes at particular locations.

Diffusers are expensive to produce, hence they cost much more than absorbers. Sellers of acoustic treatment material to the audio market push absorbers so that their sales are not constrained by the higher priced diffusers.

Don’t be fooled by sellers. Don’t follow your instincts. Learn, calculate and use your brain to design based on knowledge.
 
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dasdoing

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Decorative or not, all panels use the same structure hence have a similar response.

The OP said that the room is already small, hanging large panels away from the walls is not doable. Why suggest them? Besides, if panels will be mounted away from the wall why not use a thinner absorber? Absorber panel data is readily available. No need to suggest something without supporting data.

The only logical option on this case is to reduce the reflection from the ceiling by hanging diffusers. Players will absorb & diffuse the sound from the floor and you are left with only the walls. Once the diffusers are in place any slap echoes can then be located and treated with the mentioned absorbers. Slap echo frequency will be above 300Hz or so hence the 2in panels will be efficient enough.

Diffusion should always be the first action to tame a reverberant space. This is why concert halls are treated with diffusion. Only a few absorbers used to reduce slap echoes at particular locations.

Diffusers are expensive to produce, hence they cost much more than absorbers. Sellers of acoustic treatment material to the audio market push absorbers so that their sales are not constrained by the higher priced diffusers.

Don’t be fooled by sellers. Don’t follow your instincts. Learn, calculate and use your brain to design based on knowledge.

I don't realy have interest in discussing the perfect solution (and I don't even have the expierience (in big rooms) to do so). My intention was to present a practical and purpously satisfying solution.
Anyways, about diffusion beeing prefered, a recording room like Abbey Roads's, for example seams to be treated manly with absorbtion (though it's not easy to say from pictures)
Abbey_Road_Studios_2010-04-08_-_orchestral_recording_in_Studio_2.jpg


I don't see advantage in defusion in big rooms, as it is manly used to make rooms sound bigger. but again, I lack experience with such rooms, and as such I guess my (attempt of) construtive contibution (should) end(s) here.
 

sarumbear

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I don't realy have interest in discussing the perfect solution (and I don't even have the expierience (in big rooms) to do so). My intention was to present a practical and purpously satisfying solution.
In other words you entered a discussion and offered a solution you think is best even though in your own words you have no experience in such spaces. Meanwhile, arguing with an acoustician that he is wrong…

Anyways, about diffusion beeing prefered, a recording room like Abbey Roads's, for example seams to be treated manly with absorbtion (though it's not easy to say from pictures)
Abbey_Road_Studios_2010-04-08_-_orchestral_recording_in_Studio_2.jpg
Funny you gave the Studio 1 as an example. Care to read my about page?
 
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dfuller

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Wall mounted absorbers of about 4" thick mineral wool will help a huge amount - A company like ATS Acoustics, Acoustimac, or GIK Acoustics sells them pre-made.

Yeah, the room might be a bit more bass heavy (not to the degree foam would be, but still skewed a bit below 150ish), but the most obnoxious reflections are those in the presence region.
 

sarumbear

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Wall mounted absorbers of about 4" thick mineral wool will help a huge amount - A company like ATS Acoustics, Acoustimac, or GIK Acoustics sells them pre-made.

Yeah, the room might be a bit more bass heavy (not to the degree foam would be, but still skewed a bit below 150ish), but the most obnoxious reflections are those in the presence region.
Here are the instruments that operate at the range where your solution will have issues as you admitted. Remember that this is a rehearsal room for a concert band. Increasing the percussion instruments’ levels 6dB will create a bad listening experience.

744E7D3D-D74D-4514-83D9-D23AE71CA181.jpeg
 

dasdoing

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In other words you entered a discussion and offered a solution you think is best even though in your own words you have no experience in such spaces. Meanwhile, arguing with an acoustician that he is wrong…


Funny you gave the Studio 1 as an example. Care to read my about page?

the thing is you are so focussed in showing your knowledge that you forgot that this is a school band rehearshal room, not a professional recording room. anyways; always good to have someone spreading knowledge
 

sarumbear

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the thing is you are so focussed in showing your knowledge that you forgot that this is a school band rehearshal room, not a professional recording room. anyways; always good to have someone spreading knowledge
Ha! You are the one who is giving examples of a studio. I am giving practical advice and suggesting the use of low cost DIY solution.

Besides, yes, I am focused on knowledge. What else there to do, focus on audiofoolery?
 

TubeTrapArthur

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Greetings!

I'm looking for treatment advice for my high school concert band's rehearsal room, and having read through a number of threads here, I felt like this was the best place to start.

Some information -

The room in question is approximately 42 feet by 29 feet with 10.5 foot tall ceilings.
There are 4 windows on one of the long walls that are about 4 feet by 4 feet, the rest of the wall is cinder block.
One of the short walls is faced with drywall and has some built in shelves that are carpeted. It also has an open doorway to the office/practice room area that is 5ish feet by 8ish feet.
The two remaining walls are solely cinder block construction.
The floor is polished concrete.
The ceiling is covered in what would be considered an "acoustic tile" to the the architects that designed the building in the late 50s/early 60s. Behind those tiles is plaster.
The ensembles that currently rehearse in this room range in size from 25 to 60 players.

As the room sits, there is no other acoustic treatment other than some door seals on the doors out to the hallway, and the room is very live/wet/loud. I'd like to tame it down enough to be able to pick out finer details, and help preserve the group's hearing. Should I be focusing my treatment more on absorption than diffusion?

Most of the reading I've done so far (on this forum and other places) is mainly focused in the theater and listening room realms, and I'm just not sure if those guidelines are a good starting point for us. I do plan on getting an RTA mic and running REW in the room to get some starting data once the building opens back up on August 1st.
I'm acoustical engineer in audio. I've also worked on band rooms.
First begin by playing the room in it's naturally best orientation.
That is always where I start, regardless of hifi, HT or in your case a band room.....
This usually means rearranging where the sound sources (instruments) are located and which way they are facing (you).

Try this, place your back against the long wall, for example the one with the windows and
spread the band out left to right throughout the 42' width of the room.
This will get you closer to all the players and help you hear who is on and off tune/tempo/time

Regardless you only need to hear the band sound one time to know what is going on,
and the bounce off the wall behind you is not helping. You want to quiet the wall behind you, adding absorption.

Beware of "heavy curtains", they are usually not acoustic curtains.
Rose City stage curtains are heavy and air tight, so light doesn't leak through.
This means sound also doesn't pass through them but is reflected by them.
When the curtains are dropped there is a sound wall located between the stage activity and the audience.
A sound absorbing curtain is a heavy curtain you can with effort press your lips against it and blow air through it.
The sound curtain has to be heavy enough so sound doesn't move it and has to be porous enough so sound barely passes through it.

Is the office next to the window long wall or the opposite long wall.
Usually we want the conductor to have his/her back against the long wall that is adjacent to the office.

Which wall do students come in and leave. Where are the instruments stored?

How many roll around black or white boards do you have? Can you get more?
Do you use both sides or just one side. These can become portable sound absorbers/diffusers.

Sheetrock behind acoustic tile kinda defeats how it works. Why is the sheetrock there? Is it glued down? Does anyone know?
Sheetrock behind acoustic tile increases the STC or soundproof rating of the tile.
Is there something that connect to the overhead space that needs to be protected from band noise? What is it?
The sheetrock backing keeps sound from getting out of the band room which means it keeps sound inside the band room.

Music stands......what are they and how many do you have?
How about buying a bunch of low cost acoustical foam and gluing a piece to the back of each music stand tray..
This will reduce the volume of sound within the band by distributing absorption throughout the band.

I look forward to hearing back from you. I hope some of these ideas ae helpful.....
Oh, is there carpet on the floor?

Art Noxon
President
Acoustic Sciences Corp
 

sarumbear

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I'm acoustical engineer in audio. I've also worked on band rooms.
First begin by playing the room in it's naturally best orientation.
That is always where I start, regardless of hifi, HT or in your case a band room.....
This usually means rearranging where the sound sources (instruments) are located and which way they are facing (you).

Try this, place your back against the long wall, for example the one with the windows and
spread the band out left to right throughout the 42' width of the room.
This will get you closer to all the players and help you hear who is on and off tune/tempo/time

Regardless you only need to hear the band sound one time to know what is going on,
and the bounce off the wall behind you is not helping. You want to quiet the wall behind you, adding absorption.

Beware of "heavy curtains", they are usually not acoustic curtains.
Rose City stage curtains are heavy and air tight, so light doesn't leak through.
This means sound also doesn't pass through them but is reflected by them.
When the curtains are dropped there is a sound wall located between the stage activity and the audience.
A sound absorbing curtain is a heavy curtain you can with effort press your lips against it and blow air through it.
The sound curtain has to be heavy enough so sound doesn't move it and has to be porous enough so sound barely passes through it.

Is the office next to the window long wall or the opposite long wall.
Usually we want the conductor to have his/her back against the long wall that is adjacent to the office.

Which wall do students come in and leave. Where are the instruments stored?

How many roll around black or white boards do you have? Can you get more?
Do you use both sides or just one side. These can become portable sound absorbers/diffusers.

Sheetrock behind acoustic tile kinda defeats how it works. Why is the sheetrock there? Is it glued down? Does anyone know?
Sheetrock behind acoustic tile increases the STC or soundproof rating of the tile.
Is there something that connect to the overhead space that needs to be protected from band noise? What is it?
The sheetrock backing keeps sound from getting out of the band room which means it keeps sound inside the band room.

Music stands......what are they and how many do you have?
How about buying a bunch of low cost acoustical foam and gluing a piece to the back of each music stand tray..
This will reduce the volume of sound within the band by distributing absorption throughout the band.

I look forward to hearing back from you. I hope some of these ideas ae helpful.....
Oh, is there carpet on the floor?

Art Noxon
President
Acoustic Sciences Corp
Hi Art. Welcome. You may want to get in touch with @AdamG247 and ask his advice if you want to convert your profile to a manufacturer if you want to post in a commercial capacity.
 

youngho

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Greetings!

I'm looking for treatment advice for my high school concert band's rehearsal room, and having read through a number of threads here, I felt like this was the best place to start.

Some information -

The room in question is approximately 42 feet by 29 feet with 10.5 foot tall ceilings.
There are 4 windows on one of the long walls that are about 4 feet by 4 feet, the rest of the wall is cinder block.
One of the short walls is faced with drywall and has some built in shelves that are carpeted. It also has an open doorway to the office/practice room area that is 5ish feet by 8ish feet.
The two remaining walls are solely cinder block construction.
The floor is polished concrete.
The ceiling is covered in what would be considered an "acoustic tile" to the the architects that designed the building in the late 50s/early 60s. Behind those tiles is plaster.
The ensembles that currently rehearse in this room range in size from 25 to 60 players.

As the room sits, there is no other acoustic treatment other than some door seals on the doors out to the hallway, and the room is very live/wet/loud. I'd like to tame it down enough to be able to pick out finer details, and help preserve the group's hearing. Should I be focusing my treatment more on absorption than diffusion?

Most of the reading I've done so far (on this forum and other places) is mainly focused in the theater and listening room realms, and I'm just not sure if those guidelines are a good starting point for us. I do plan on getting an RTA mic and running REW in the room to get some starting data once the building opens back up on August 1st.
There is a relevant chapter (12) in Kleiner & Tichy's Acoustics of Small Rooms. You can get a sense of the discussion here: https://www.google.com/books/editio...rooms+for+music"&pg=PA378&printsec=frontcover

Along with the references above, you can find more (though more of an orchestral focus) here: https://ateliercrescendo.ac/design-...-orchestras-part-2-some-acoustic-design-tips/

Probably you should focus on absorption, and you may get more bang for buck by starting with a greater number of smaller pieces (though preferably at least 4-6" thick) distributed closer to the centers of two non-opposing walls. K&T suggest perhaps a diffusive surface behind rear-firing instruments like French horns. Geometric would be cost-effective--could even just experiment relatively inexpensively with a number of different-diameter Sonotubes in order to avoid repeating sequence, later can cut and/or finish (https://gearspace.com/board/bass-traps-acoustic-panels-foam-etc/266361-sonotube-diffusor.html, https://www.lifewire.com/make-your-own-audio-diffuser-3134903).
 
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