Soundproofing a room to prevent sound from disturbing neighbors?

Hi folks,

So I am planning to have a couple of PA speakers (4 Yamaha DBR10 10" active PA speakers + 2 Mackie Thump 118s 18" subwoofers) in my basement as part of my speaker setup. However, I hope to be able to crank the volume of my speaker system while being a considerate neighbor by reducing the amount of sound escaping the room. Are there any soundproofing solutions that allow me to soundproof my basement without tearing down/rebuilding my wall? The basement of my house already has carpet on the floors, and I feel that it would be impractical for me to rebuild the walls of the basement or tear off the carpet just to soundproof my room. I'm looking for a solution that has a STC level greater than 80, so that, for example, if I play my speakers at 100db, only 20 db of sound will escape the room so that it is quiet enough not to disturb my neighbors, assuming the walls have an STC of 80. Any ideas?
 
I suppose your house and basement has no walls connecting to your neighbours? In this case you should just avoid any air leaks allowing sound pressure to escape. Ventilation holes will need silencers/mufflers, doors and windows need to be air/sound proof (sealing and adding weight will help).
If your basement structure however is connected to your neighbours house/appartment you need to make sure that sound is not transmitted via the structure. You may need to install a "box in the room" or similar to isolate sound.
 
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I suppose your house and basement has no walls connecting to your neighbours? In this case you should just avoid any air leaks allowing sound pressure to escape. Ventilation holes will need silencers/mufflers, doors and windows need to be air/sound proof (sealing and adding weight will help).
If your basement structure however is connected to your neighbours house/appartment you need to make sure that sound is not transmitted via the structure. You may need to install a "box in the room" or similar to isolate sound.
Yes, my house is not connected to my neighbors, it is just a regular suburb house. I would try to implement the following steps you said above. However, even if I increase the mass of my doors and windows, is there any way you suggest to increase the mass of my walls, without destroying them? I'm wondering if products such as MLV will help attenuate the music from the speakers from escaping my basement. Also, I am not that concerned about soundproofing my basement to reduce the sound in other rooms within the house, but my main goal here is just to prevent the music from escaping the house and potentially annoying my neighbors
 
is there any way you suggest to increase the mass of my walls
If the walls are below surface you don't need any additional weight in my opinion. Also, basement walls are usually made of heavy material, so no need to do anything in my opinion.
Of course you could add a plasterboard or wood shells in front of the wall(s), filling the void behind with damping material (rockwool) and making sure the shell is monted with flexible brackets.
The flexible shell will absorb some of the acoustic energy.

For the ultimate solution see:
https://www.soundonsound.com/techniques/practical-studio-soundproofing-part-4
 
A STC of more than 60 is hard to realize and one of 80 is virtually impossible with normal building constructions. Is your basement partly above ground level? Is the first floor a concrete slab? What construction are we talking about? Is there a door opening or window to the outside? You need to consider sound transmission through walls, windows/doors, ceiling, leaks and flanking transmission. Find the weakest spot and start there.
 
Of course you could add a plasterboard or wood shells in front of the wall(s), filling the void behind with damping material (rockwool) and making sure the shell is monted with flexible brackets.
I recommend 3/4" plaster over wood lathe. My house walls are built of that, and nobody complains when I blast rock&roll from the hifi or play piano at 3 AM. Plaster is mortar built of cement & sand.
Applied with a trowel. If you don't want to do that you can stack up EPS block: https://www.supplyhouse.com/Diversi...ping&msclkid=d0d85d0dea1b1531502d39d6592f520e
Windows, you could replace glass with glass block, or 1/2" polycarbonate plastic.
 
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Play your music at say 100db and then go outside to your property line to see just how much sound is actually traveling to your neighbor’s house. If it’s problematic, start identifying where the sound is coming from (Google flanking sound) and start treating.

Windows will always be a usual suspect. Getting rid of them will help reduce sound transmission a lot, but I’d rather keep the windows and just turn it down.
 
A STC of more than 60 is hard to realize and one of 80 is virtually impossible with normal building constructions. Is your basement partly above ground level? Is the first floor a concrete slab? What construction are we talking about? Is there a door opening or window to the outside? You need to consider sound transmission through walls, windows/doors, ceiling, leaks and flanking transmission. Find the weakest spot and start there.
Oh really? I didn't know that. Out of curiosity, what are the special building constructions that would be used in order to achieve a STC of 80? I am guessing it would be isolating the room structure so that sound would not transmit due to an air gap, especially isolating low frequency sounds. Yes my basement is 1/3 above ground level, and 2/3 under, and the first floor is not a concrete slab (the floor above the basement). However, it is an unfinished ceiling so this makes soundproofing easier hopefully. There is one door to the hallway, but 2 small windows to the outside. I would try to do as you said and patch-up the weakest links to hopefully contain sound
 
I recommend 3/4" plaster over wood lathe. My house walls are built of that, and nobody complains when I blast rock&roll from the hifi or play piano at 3 AM. Plaster is mortar built of cement & sand.
Applied with a trowel. If you don't want to do that you can stack up EPS block: https://www.supplyhouse.com/Diversi...ping&msclkid=d0d85d0dea1b1531502d39d6592f520e
Windows, you could replace glass with glass block, or 1/2" polycarbonate plastic.
Interesting. I am guessing the function of the plaster is to fill in the gaps of the wood lathe in order to minimize the gaps for sound to travel through. I am a little doubting about the effectiveness though, since it takes a large mass in order to stop sound waves and it's interesting how such a supposedly thin wall structure could reduce transmission of loud music. EPS blocks sound like an interesting solution, but how thick would you recommend the EPS walls to be? Also is it expensive to get in large quantities? For the windows, I am considering using acrylic or acoustic blankets to prevent the sound from escaping from there, or increase the sealing of my windows.
 
Play your music at say 100db and then go outside to your property line to see just how much sound is actually traveling to your neighbor’s house. If it’s problematic, start identifying where the sound is coming from (Google flanking sound) and start treating.

Windows will always be a usual suspect. Getting rid of them will help reduce sound transmission a lot, but I’d rather keep the windows and just turn it down.
Yes, I would try that, and I believe the windows are a big reason. I can hear cars pass by my house somewhat clearly, so if sound could get into my room, the sound would easily leave my room as well. So I believe that I should increase the STC of the windows.
 
You could install secondary or tertiary glazing to aid the reduction of sound transmission through the windows, whilst allowing you to maintain light / ventilation (when not playing loud music).

I used to work as an acoustic consultancy and where we did work on performance spaces, i.e. music practice rooms next to each other and a main show hall, the floor slabs were independently cast and were floating, i.e. on a damping material to prevent cross-talk, the walls were on independent studs built off the different slabs and consisted of three layers of plasterboard (12mm Gyproc, 12mm Soundbloc, 12mm Gyproc (staggered overlaps) with mineral wool between the studs. Non-setting caulking was used for any joints. Ceiling was a similar construction. Silencers (as someone mentioned) were typically a steel construction with 50mm of mineral wool held in place with a perforated sheet with a minimum of a 50% open area. Two fire doors with acoustic seals were used to get into the performance spaces, again one mounted to the inner stud, the second to the outer stud.

Constructed well, these provided very good STC. Typically, the thing that starts to undo things is where there are direct transmission paths, which come from cables and services that need to enter the space.

I suspect this might be overkill for what you need, but might provide a few ideas.

Doors, windows and your basement ceiling would be my focus.
 
Doors and windows leak the most sound.
Basements were room of choice for band days.
Insulation and sheet rock worked well for uncovered walls and ceiling.
Best setup was a room within a room.
We added a room inside a large basement that wasn't attached to any outside walls.
Very basic OSB walls.
You can double sheet or use concrete sheetrock / Cement boards for more density.
Band levels are much louder of course, windows were fully stuffed and boarded over.
Mids and highs disappear quickly with minimal effort. Bass is the tough one.
Taking To extreme isolate upper rooms floating ceiling/ airgap and insulation.
For home HiFi and theatre levels. Just adding insulation and finished walls/ceiling works.
Nothing too extreme, the windows and doors leak sound no matter what.

In garage days same thing, just added walls and insulation.
Carpet over doors and windows or boarded over with plywood.
We have tried extreme measures, waste of time ..bass will be bass.
One guitar player had a large waterfall in the backyard.
And the ambient white noise would hide some sound.
Sounds silly. Neighbors never complained for months.
Then one day forgot the waterfall pump. first complaint.
We didn't believe it either, till we tested it.
 
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RC-1 resilient channels are steel members designed to flex. They are attached to the studs and the gypsum board is fixed to the channels to increase the STC performance of the assembly.

Like all sound proofing construction detailing, they have to be installed carefully.

http://www.usg.com/content/dam/USG_...hed_assets/acoustical-assemblies-en-SA200.pdf

RC-1 Pro_0.png
 
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Floating ceilings with the channels good for tenant situations.
Reduces thump thumps and basic human ambience.
For high spl, with windows n doors dont do much.
For tenants and especially the clunk clunk of upstairs wood floors.
And lower tenant conversations / children and average TV/ Radio ambience
It is rather nice.
 
2 Mackie Thump 118s 18" subwoofers
No hope, no matter what you do - for those infra-sonics anyway. Ever hear certain automobiles drive past your house? That stuff (alternating +/- Pressure wave) sails through common house structure like it's not even there. At least our house...

If you give up the P wave and go to V wave, as would be from an OB setup, that doesnt get far. Of course, that's a matter of taste; many listeners dont perceive V wave in the same way, aka "where's the bass". If I cannot feel it viscerally, therefore it doesnt exist.

Personally I find V wave bass pleasant to listen to. Outside of the near field it's gone. Of course, I'm old and music doesnt do the same thing for me as it did when I was 20 - particularly around SPLs as in "turn it up".

One time when I lived more out in the country, someone somewhere must have been playing a system outdoors. All I could hear was the bass, which was suffucuently loud where I was standing out in basically an open field. I could not locate the direction from which it came; as an audiophile I wanted to know what kind of speaker they were using. God only knows how far or near the - I assume P wave - source was; it was an astounding effect that I've never heard before or since.
 
  1. Talk/listen to your neighbors and quantisize the problem.
  2. Prepare to install triple glazing with big gaps and unequal glass thickness.
  3. Search for possible leaks, ventilation appliances and construction deficiencies being the first suspects.