Help Soundproofing 9FTx9FT Bedroom

[kibbles]

I'm going to attempt to soundproof my room with acoustic panels, but I could use some help and information since I've never tried this before.

I'm also open to better ideas if there are any.

Budget: $300

Mission:

I mainly just need my room to be soundproof enough to prevent anyone outside of my room from hearing noises inside of my room. Noises that are about 30% louder than normal talking volume.
Not only do I want to prevent eavesdropping if I'm having a conversation with a guest or over the phone/internet, but I also don't want to disturb others in nearby areas of the house if I'm watching videos or playing music through speakers.

Workload:

There needs to be soundproofing on all 4 walls of the room. The ceiling is out because there's no one above my room anyway, and the floor is out because there likely aren't any practical options for me there.
On the other side of the first wall there is another bedroom, behind the second wall is a hallway, behind the third wall is a frequently used area of the house, and behind the fourth wall is outside.

I'd say that the fourth wall will need the least soundproofing (likely only on the windows), since it's naturally more difficult to hear sounds from my room from outside, even if my window is open.
The other three walls need about equal treatment.

Soundproofing:

Budget: $300

First of all, what's so special about acoustic foam? I've seen it in action in videos, and it clearly works for echo reduction and soundproofing, but why?
Is it a special type of foam or just regular foam?
The prices are pretty insane if it's just regular foam.
Which patterns/styles of acoustic foam are more effective?

I got this idea when I saw a video of some guy soundproofing his room by covering all of the walls in acoustic foam. Seems like it works very well. (https://www.youtube.com/watch?v=zJoS58_Wz2c)
My budget won't allow for covering the walls as much as that, but I believe there are ways I can help make up for it.

Does anyone know if the 2 inch thick foam is significantly more effective than the 1 inch thick foam for this task?
If I can find 1 inch thick foam instead the price might be a bit lower, but if it's significantly less effective then perhaps it's not worth it.

Part 1:

Anyway, I estimate I won't need more than 60 acoustic panels, but I could be wrong and may end up needing up to 84. It's not the end of the world if it turns out that I need more. I could buy the additional amount another time.

The 2 inch thick panels I'm looking at will be about $170 for 60 of them.
The 1 inch thick panels I'm looking at are sold in packs of 50. 100 of them will be $150.

You could argue that going for the 1 inch thick ones will allow me to place more at a lower cost, but the smaller thickness may be less effective and not do as good of a job.

Part 2:

I want to maximize the effectiveness of these panels. According to this soundproof expert (https://www.youtube.com/watch?v=GLjhrXFo0Kw) if you have multiple layers of walls, ceilings, insulation, ETC, it will dampen sound significantly more.

Obviously I don't have the option of going to that length, but perhaps I can apply the same concept with the acoustic panels. I don't know if that will actually be effective, so if anyone knows or has experience with that, advice would be greatly appreciated.

I've seen people use slabs of cardboard to place the acoustic panels onto, and then stick the cardboard onto the wall.
I can't find decently sized cardboard at a good price, so I'm thinking I'll use bristol boards instead.

I'll take two sheets of bristol board and stick them together with an adhesive. In between the two sheets of bristol boards will be slabs of wood or something else (like a less expensive type of foam) in order to create a similar effect of having space between multiple walls, and then the acoustic foam will be place on top.
Alternatively, I can use the acoustic foam between the bristol boards as well as on top of it (or would that be counterproductive?). This would require buying more acoustic foam though.

On top of the bristol boards I can double up on the acoustic foam, placing them on top of each other. That will also require buying more acoustic foam.
Would that actually help to further soundproof my room?

If these methods aren't too effective, what can I do to increase the effectiveness?
Are there any better ideas?

Part 3:

What is the most effective way to layout the panels on the wall if I can't cover the entire wall?
Which position on the wall should the panels be placed?

[Sam Spoons]

Hi and welcome, the best think I can suggest is that you read Eddy's thread here https://www.soundonsound.com/forum/view ... hp?t=74805 before embarking on your project. but in answer to a couple of questions on the basics of soundproofing, as opposed to 'acoustic treatment' (you seem to understand the difference as you say "First of all, what's so special about acoustic foam? I've seen it in action in videos, and it clearly works for echo reduction and soundproofing, but why?") firstly foam is pretty much completely ineffective as soundproofing. It does work (though is not the best solution) as acoustic treatment, reducing reverberation within a room. Secondly, $300 will let you achieve a significant improvement in you room for listening to music/dialogue but will barely scratch the surface WRT soundproofing. For the latter start by making sure all doors and windows are gap-sealed along with any other gaps (but paying attention to maintaining some ventilation).

[Drew Stephenson]

What Sam said ^^^.
Sound-proofing and sound-treatment are different things.
Sound-proofing is controlling the amount of sound entering and leaving the room. This is difficult and expensive.
Sound-treatment is controlling the sound within the room. You can get good results here much more simply and cheaply.
In short, $300 carefully spent will allow you to do good work on sound-treatment but probably won't do a thing on sound proofing unless you're starting with an exceptionally isolated room.

[RichardT]

Unfortunately, acoustic treatment won’t soundproof the room. I’m no expert on soundproofing (there are some here, though) but it normally involves significant amounts of work and money.

I honestly think you would be better off investing in a great pair of headphones and listening through those.

[kibbles]

I heard about soundproofing and sound dampening before but I didn't know the details about what the differences are.

In this case, I want to sound dampen my room, preventing people outside of my room from hearing sound inside of my room, up to about 30% louder than normal talking volume.

The walls are already thick enough that people outside of my room aren't always able to hear normal speaking volume in my room.

To be clear, I believe that people outside of my room can hear the gist of what I say when speaking at normal volume if they are very close to my room, and it's also not too noisy outside of my room. For example, if a fan is running outside of my room, the noise from the fan should prevent them from hearing normal speaking volume.

The problem is a fan cannot be running always. I need to tackle this problem mostly from within my room, at least for the most part.
I have the option of placing some acoustic treatment on the walls and door outside of my room, but only in limited capacity. Although I'm not sure if placing acoustic treatment outside of my room will affect the sound coming from inside of my room unless it is fairly thick padding.

[Eddy Deegan]

Hi there, and welcome to the forum

I'm going to attempt to soundproof my room with acoustic panels

I'm afraid the bad news is that you can't soundproof a room with acoustic panels. You can treat the room in order to better judge the sound coming from your monitors but this is a completely different thing to soundproofing.

Budget: $300

More bad news I'm afraid. Soundproofing is expensive, even for a relatively small room. Also, it would require reducing the size of the room due to the thickness of the materials involved and/or the construction techniques you need to employ, which will vary depending on the nature of the building the room is in.

To give you an idea, the soundproofed wall separating my studio from the neighbouring house is about 14 feet long and 26cm / 10" thick, of which 2.5" is pure soundproofing and the rest is a dense insulation. This is all in addition to the (mostly brick) wall that was there prior to my commencing the process. The cost of that section of the project alone was well into 4 figures.

The soundproofing on the rest of the walls and ceiling is about 6cm / 2.3" involving heavy, expensive materials and in all cases there is still at least 10cm / 4" of dense insulation behind that.

I could go on, but I'm afraid it's simply not possible to spend your $300 usefully if you're trying to soundproof a room. Acoustic treatment, absolutely, but not soundproofing.

Sorry to be the bearer of bad news but there's no point spending money for no real benefit.

[Wonks]

I honestly think you would be better off investing in a great pair of headphones and listening through those.

Unfortunately the primary concern is not having face to face conversations overheard so headphones won't do in this instance.

One option for the corridor scenario would be to have a small speaker outside your room though which you could play back pink noise at a level loud enough to mask what you are saying. You could just turn this on when having a private conversation (though you'd need to remember to do so). Obviously the noise level would need to be acceptable to other house members, but it only needs to be loud enough to stop what you're saying from being understood, not the fact that you are speaking.

But if people can clearly hear you in adjoining rooms, then that's not going to work for them.

[Eddy Deegan]

If these methods aren't too effective, what can I do to increase the effectiveness?
Are there any better ideas?

I had an afterthought that might be worth considering/looking into. Whereas there really is no way you can soundproof the room without spending a significant amount more than you've mentioned, if you're merely looking to reduce the amount of sound that travels through the walls then there is a possibility that might help.

I'm not going to claim it'll do the job you want but it's the only thing I can think of remotely close to your budget and it's mass loaded vinyl.

If you were to cover the walls, or drape them (draping would probably be better as the vinyl can move), with mass loaded vinyl then the amount of sound escaping would be less than it is now. As to how much less I can't say without more information about the construction of the building and there is a good chance it still wouldn't be enough to meet your requirements but in the absence of anything better it's worth mentioning.

Acoustic panels, foam or thick padding simply won't work though. They don't have enough density/mass.