Thermafiber R Numbers. Which one for corner bass traps?

[DtotheC]

Im working on building my corner bass traps. Looking at the Thermafiber available at local hardware store. Is this product going to work? From some research Ive done people are discussing density. I dont need some crazy perfect sounding room, but I want the room acoustics to improve on the low end. I also dont want to waste time and money building bass traps only to find they are not effective.

 

[witchdoctor]

IDK about thermafiber, I have heard mostly about owen cornings 703 and rockwool.

 

[OHMisback]

If you know what's going on first you can tailor what you're doing. You can waste money or spend it along with a little research
and come up with a better solution.

Remember what you are putting in your room. You can wind up breathing it or worse your kids and pets. I always used packing
blankets for that reason. They work better, but they CAN be a bit heavier. Run your own test to check what 3-5 vs 5-7 layers will
dampen. It's Not hard to run your own test and see for yourself with a simple microphone and test tones.
The biggest thing is it won't wind up 3/4 worthless and still take up the space that needs to be treated. Usually corner bass traps
are not deep enough to have any effect. I test their spec. It's as simple as that. I use my mics and my shop to test in. I don't care
who says what.

I've seen more people waste money on crappy studio foam $hit than anything else. Totally worthless unless your making a little
mixing studio. Ugly too.

 

[highfigh]

Im working on building my corner bass traps. Looking at the Thermafiber available at local hardware store. Is this product going to work? From some research Ive done people are discussing density. I dont need some crazy perfect sounding room, but I want the room acoustics to improve on the low end. I also dont want to waste time and money building bass traps only to find they are not effective.

R numbers mean absolutely nothing when it comes to sound. You need to be concerned with NRC (Noise Reduction Coefficient) and STC (Sound Transmission Coefficient). These specs are always shown on the manufacturer's website and are absolutely necessary for determining the sound deadening characteristics of a building material.

When you see NRC of .3 or whatever is shown, it means that the material absorbs 30% of the sound at that frequency. Nothing is as efficient in the low end as it is in the midbass-high frequencies, so that means you'll need more area and volume in order to treat those frequencies to the extent needed.

You DO NOT need to cover the walls & ceilings completely and if you do, it will be a terrible experience.

Owens-Corning rigid panels are great, but they do shed some fibers- if that concerns you, maybe something like Roxul or the one you're already looking at.

If you don't know how to determine the amount and type of absorption you need, hold off doing it until you learn- it will be worth the wait because you're less likely to become extremely frustrated.

FWIW, I used Owens Corning panels in 1", 2" and 4" thicknesses, mostly 2' x 4' and a few that are 1' x 4'- I had made them for a theater I was working on to help someone else in the business and as it turned out, they weren't needed, so I kept them. When I found that my room had problems that couldn't be solved by repositioning speakers, furniture, etc, I brought the panels in and used REW to watch the response as I positioned the panels. They did the job and I haven't felt the need to make any changes since. For the record, I took a college level class in Acoustics and did a lot of reading over the 45 years I have been in the business, as well as many discussions with people who know more than I do about the subject.

You can contact acoustical material manufacturers and dealers for help, too- GIK is one of them.

 

[BMXTRIX]

There is a specific page that discusses the NRC numbers for this material. It also looks like it is a specific material which has been tested for noise reduction, so the generic Thermafiber may not be the same, and to that point, likely isn't the same as their SAFB material.

https://dcpd6wotaa0mb.cloudfront.net/mdms/dms/EIS/10021143/10021143-Thermafiber-SAFB-Data-Sheet.pdf?v=1632758305000

 

[DtotheC]

IDK about thermafiber, I have heard mostly about owen cornings 703 and rockwool.

Thermafiber is mineral wool made by Owens Corning.

 

[DtotheC]

If you know what's going on first you can tailor what you're doing. You can waste money or spend it along with a little research
and come up with a better solution.

Remember what you are putting in your room. You can wind up breathing it or worse your kids and pets. I always used packing
blankets for that reason. They work better, but they CAN be a bit heavier. Run your own test to check what 3-5 vs 5-7 layers will
dampen. It's Not hard to run your own test and see for yourself with a simple microphone and test tones.
The biggest thing is it won't wind up 3/4 worthless and still take up the space that needs to be treated. Usually corner bass traps
are not deep enough to have any effect. I test their spec. It's as simple as that. I use my mics and my shop to test in. I don't care
who says what.

I've seen more people waste money on crappy studio foam $hit than anything else. Totally worthless unless your making a little
mixing studio. Ugly too.

Appreciate the feedback. I like the packing blanket idea as I just happen to have a bunch of extras.

 

[DtotheC]

R numbers mean absolutely nothing when it comes to sound. You need to be concerned with NRC (Noise Reduction Coefficient) and STC (Sound Transmission Coefficient). These specs are always shown on the manufacturer's website and are absolutely necessary for determining the sound deadening characteristics of a building material.

When you see NRC of .3 or whatever is shown, it means that the material absorbs 30% of the sound at that frequency. Nothing is as efficient in the low end as it is in the midbass-high frequencies, so that means you'll need more area and volume in order to treat those frequencies to the extent needed.

You DO NOT need to cover the walls & ceilings completely and if you do, it will be a terrible experience.

Owens-Corning rigid panels are great, but they do shed some fibers- if that concerns you, maybe something like Roxul or the one you're already looking at.

If you don't know how to determine the amount and type of absorption you need, hold off doing it until you learn- it will be worth the wait because you're less likely to become extremely frustrated.

FWIW, I used Owens Corning panels in 1", 2" and 4" thicknesses, mostly 2' x 4' and a few that are 1' x 4'- I had made them for a theater I was working on to help someone else in the business and as it turned out, they weren't needed, so I kept them. When I found that my room had problems that couldn't be solved by repositioning speakers, furniture, etc, I brought the panels in and used REW to watch the response as I positioned the panels. They did the job and I haven't felt the need to make any changes since. For the record, I took a college level class in Acoustics and did a lot of reading over the 45 years I have been in the business, as well as many discussions with people who know more than I do about the subject.

You can contact acoustical material manufacturers and dealers for help, too- GIK is one of them.

Thanks! GIK really only wants to sell their products. Im looking to pick up local if possible. I will order online if I have to for proper sound. Lots of research and testing to do. Ugh

 

[DtotheC]

There is a specific page that discusses the NRC numbers for this material. It also looks like it is a specific material which has been tested for noise reduction, so the generic Thermafiber may not be the same, and to that point, likely isn't the same as their SAFB material.

https://dcpd6wotaa0mb.cloudfront.net/mdms/dms/EIS/10021143/10021143-Thermafiber-SAFB-Data-Sheet.pdf?v=1632758305000

This is a great resource! Ill check it out.

 

[OHMisback]

Appreciate the feedback. I like the packing blanket idea as I just happen to have a bunch of extras.

I just picked up 20 pieces from Harbor Freight 5.50 or 6.50 each. 24" X 48" X 3.5" thick frames (4 or 5 pieces) X 5.5" thick (6-7 pieces).
About 20.00 usd for soft material and then the frame. Tear down the neighbors shed. I use them for walls I don't use corner traps.
Tuning tubes, wall treatment and floor to ceiling drapes. I had to do the ceiling and floor in front of the seated position.
Open the drapes to liven the room or if your not using a TT. Easier to tune for different music or HT use.

 

[highfigh]

Thanks! GIK really only wants to sell their products. Im looking to pick up local if possible. I will order online if I have to for proper sound. Lots of research and testing to do. Ugh

GIK will help design the acoustics in the room. Call them and find out for yourself. They can help you bypass the research which, admittedly, is considerable and that allows you to learn more about it as you go, rather than being in crunch time 24 hours a day.

 

[DtotheC]

https://dcpd6wotaa0mb.cloudfront.net/mdms/dms/EIS/10025220/10025220-Thermafiber-Fire-and-Sound-Guard-Plus-PDS.pdf?v=1660211341000

Here is a link to the product from Home Depot/Lowes. And some pictures of my bass trap design using dowels. Im thinking the rounded edges will make the corner traps look cleaner when wrapped with fabric.

 

[fmw]

I can't imagine why the R number would matter. You aren't insulating for temperature. You are trying to reduce reflections in the corner. Anything that absorbs sound should suffice.

 

[highfigh]

https://dcpd6wotaa0mb.cloudfront.net/mdms/dms/EIS/10025220/10025220-Thermafiber-Fire-and-Sound-Guard-Plus-PDS.pdf?v=1660211341000

Here is a link to the product from Home Depot/Lowes. And some pictures of my bass trap design using dowels. Im thinking the rounded edges will make the corner traps look cleaner when wrapped with fabric.

Look at the second page of your link- it shows 'Acoustical Performance' and below that header, it shows thicknesses and the NRC at various frequencies. At 125Hz, the NRC is only .33, so you'll need at least three layers of 2.5", but if you look, the absorption doesn't necessarily double when the thickness is doubled, so you'll need to work with it to get the results you want and that can only happen after you do some testing, to find the problem frequencies.