Tips for DIY room treatment

Polyster wool, IMO, is not hazardous compared to the others but it is not as effective. I have used this in some of my DIY builds and was easy to handle. If all else fails it is better than nothing.
 
Polyster wool, IMO, is not hazardous compared to the others but it is not as effective. I have used this in some of my DIY builds and was easy to handle. If all else fails it is better than nothing.
Ok was convinced with rockwool till today but when the person visited to take measurements advised that my room is small and stuffing it with to many panels and corner bass traps may cause problems so he was advising to go for polyester wool. He said we can get about 70% performance of rockwool. So I am researching if it can really perform 70% close to rockwool
 
Ok was convinced with rockwool till today but when the person visited to take measurements advised that my room is small and stuffing it with to many panels and corner bass traps may cause problems so he was advising to go for polyester wool. He said we can get about 70% performance of rockwool. So I am researching if it can really perform 70% close to rockwool

I don't think it will cause probelms but people have varying preferences for absorption vs reflection in a room among the entire bandwidth. Materials behave differently at different frequencies. If you want a more controlled tighter sound with less leakage outside then absorption is good, if you like a heavier thicker resonant sound then less absorption is better, I am talking about bass here. Try searching for the NRC values of the materials you are interested in. Do remember that in sound often 6db is considered "doubling" the SPL.
 
Is polyester wool effective and good for room treatment? Even if it is 70-80% effective as rockwool I am fine

Don't know about polyester wool (sorry) , but the panels in my room were originally filled with bonded acetate fiber (BAF). I eventually had it replaced by the Owens Corning material because I had questions about BAF's effectiveness. Suffice to say that the difference after the switch was comfortably audible. So much so that I wouldn't go back to BAF. In fact, when the panels were installed with the OC material, one of my daughters commented, unprompted, as to how quiet the room now was.
 
For corner bass trap, please do not use more than 48 kg/m3 density. If you can use loose rockwool and put it in a sack made of any sturdy yet transparent material it would be good in the top slab that you have.

I have tried triangle and square and the triangle is far better as it gives a larger face to any standing wave and it is space efficient. Not really sure of a circular bass trap and the science behind it as it will leave corner gaps.

For any bass trap you need to have a mix of absorption and gas flow, so a super absorbent slab doesn't work unless you put an air gap or you use a lower density.
 
Don't know about polyester wool (sorry) , but the panels in my room were originally filled with bonded acetate fiber (BAF). I eventually had it replaced by the Owens Corning material because I had questions about BAF's effectiveness. Suffice to say that the difference after the switch was comfortably audible. So much so that I wouldn't go back to BAF. In fact, when the panels were installed with the OC material, one of my daughters commented, unprompted, as to how quiet the room now was.
I bet the Owens cornering material is going to be very expensive. Just googled them and they seem to be an American company. Do they have dealers here or you imported the materials yourself.
 
Polywool unfortunately, doesnt come with proper absorption numbers, so its difficult to build but my guess is that its going to be useless for bass traps. With Rockwool, the advantage is it can be easily cut and laid out in the slab form. In the loose form it can used in any shape. The thing to be careful with Rockwool is you need to use gloves/long sleeves and possible goggles to avoid touch as it can get itchy. The loose form is super itchy, so I avoided it.
 
Polywool unfortunately, doesnt come with proper absorption numbers, so its difficult to build but my guess is that its going to be useless for bass traps. With Rockwool, the advantage is it can be easily cut and laid out in the slab form. In the loose form it can used in any shape. The thing to be careful with Rockwool is you need to use gloves/long sleeves and possible goggles to avoid touch as it can get itchy. The loose form is super itchy, so I avoided it.
I actually won’t be building. Found one DIY guy who builds it for a very reasonable cost. I can’t find any data or any article on the internet for polyester wool used for bass traps or panels. Reading about rockwool scared me even though there is no reports of it harming any one. Biggest concern is the room will be used for long hours on a daily basis and not only for movie watching.
 
I bet the Owens cornering material is going to be very expensive.

550 per sq.mt. for 2 inch thick (stack together for extra thickness) pieces. Eight pieces in a box for a total of 5.76 sq.mt. GST (18%) and transportation extra.


Do they have dealers here or you imported the materials yourself.

Purchased from local dealer. They typically supply to commercial establishments (theaters included). PM me if you'd like their contact.
 
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Frankly, if the below coefficients are correct, then you should avoid using polywool, it will only act as a mid to high frequency absorber.

Yeah seems very poor. Some of them have NRC of only 0.2-0.5 even for highs and mids.Bass traps quotes was more then the panels so I ain’t going to waste money on a material unless it’s proven effective for bass traps.For a 6.8 feet tall triangular bass trap he was charging 8k. Plan was to get 3 of them which will amount to 24k.
550 per sq.mt. for 2 inch thick (stack together for extra thickness) pieces. Eight pieces in a box for a total of 5.76 sq.mt. GST (18%) and transportation extra.




Purchased from local dealer. They typically supply to commercial establishments (theaters included). PM me if you'd like their contact.
Sure thank you
 
Dear Members,

I am too planning to build some acoustic panels to reduce reverberation in my HT room using the following method.


1. Make a plywood frame of around three inches thick.
2. Block the bottom side with corrugated paper. The finished side will face the wall
3. Layer 1 consists of a 2" thick rockwool of 96 Density
4. Layer 2 is made out of 0.75"-1.0" 20 D foam sheet which are used by the sofa makers
5. Layer 3 which is also top layer is made out of 0.75"-1.0" polyester wool sheet
6. A muslin cloth to cover the frame and the layers.


I think the overall panel should take care of entire frequency range. Also it will shield the rockwool slabs completely and prevent it's loose particles to escape into the air.

Please share your thought on this idea.

Thanks in advance.
 

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The reasons for using three layers are

1. I want to ensure that rockwool particles do not escape into the room.

2. rockwool is good at absorbing LF only. The other two layers will absorb the Mid and HF with a overall improvement of sound quality

Of course I feel that way. Do not claim to be technically correct.

Also do you think this model can degrade the overall sound effect?
 
Imo for stereo listening you don't need any room treatment in any normal room with standard furnishing like sofa, chairs, center table, racks and curtains. These artifact's will work like an EQ and blance out the RT60 ok n your room. Most rooms require an RT60 of around 0.3s to around 0.6s for good dynamics. If you feel like you are requiring room treatment of when normal conversation between family members are sounding normal/ good without boom/ strain then it's the hi-fi gear to blame - chiefly the speakers imbalance. I am more than 100% sure that treatment of such rooms will achieve nothing where problem lies elsewhere.

PS: I have not read any post and have directly quote with my own experience. YMMV.
 
The reasons for using three layers are

1. I want to ensure that rockwool particles do not escape into the room.
Since you are also concerned about rockwool particles have you considered looking at alternatives that doesn’t have any health risk like rockwool? I had no clue and decided on rockwool but my entire room treatment plan is on hold after reading about rockwool.
 
In my knowledge, Glass wool is substitute for rock wool and the former is proven hazardous material. Rockwool is not proven to be dangerous but it's definitely a irritant for the respiratory system. Also rock wool doesn't emit any toxic gas. The only concern is it should not go inside human body through breath.

I think my proposed method will almost eliminate the chances of particles escaping in to the room. The whole job will be done in the open terrace and after thorough cleaning it will be fixed in it's place. It seems to me that this should be a much better room treatment than the egg crate foam.

Any comments will be appreciated
 
So came across a product called echo eliminator which is made out of recycled cotton while researching on denim insulation. The NRC rating is good. I am guessing this should have all the properties of denim insulation right? Denim is claimed to be safe compared to rockwool and glass wool.


 
I couldn’t get hold of denim so finally decided to go with 1800gsm 50mm polyester wool. First I am going to make panels alone and see how effective it is comparing before and after measurements. If I find them to be good will make bass traps using polyester wool. The person who is going to build the panels shared this spec sheet from the manufacturer who is supplying the poly wool
 

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