Rockwool OR Fiberglass for DIY sound panels?

[@BelindaCarr]

Many people have commented on testing different frequencies (which I hadn't thought of!). I did some quick tests today and got the same results. Fiberglass was surprisingly the best. Check out John Brandt's explanation: kzbin.info/www/bejne/aZ6qk4N-rcRrjpo

[@DeanTheDoctor]

Thanks so much for doing this one! 🌎☺️✌️

[@nayudusrini]

Belinda, thanks for doing this. But I think big miss here is, the frequency spectrum. It is expected Roxul Safe N Sound Rockwool bats would do much better in lower frequency spectrum which is very tough to contain compared to high frequencies. If you look at STC ratings of various insulation you might see that reflected. But I would like to see, you perform that test and provide results, which I trust more much than other's tests done with commercial interest.

[@SinnisjInsulator]

I would think fiberglass does well because it's more bouncy and fluffy therefore absorbs the sound waves a little better.

[@SinnisjInsulator]

@@nayudusrini that's interesting, didn't think about different frequencies would matter but it makes sense. The products funny enough only gives one number on the package.

I'm sorry, but this is only acoustic correction. So they can alter the acoustic quality of the room they're in but do nothing to "insulate". For insulation you need "mass, spring, mass" and air tightness. Those panels won't help in acoustic insulation. The only thing they do is diminish reflection and resonance.

[@beachton]

The fiberglass dropped the sound pressure level more than the other materials because of the Kraft paper backing. All you were testing was airflow. The panels you hang on the wall are meant to reduce the amplitude of sound waves reflecting back to the source from the walls. You’d need to put the SPL meter on the same side of the treatment as phone to see how the insulation works to dampen reflections. What you showed is that if you want to stop outside sounds getting in any improvement in airtightness will help. Get an airtight storage container from your kitchen and put the phone in there making the noise and check the sound pressure level. It should be better than any insulation.

[@troelsnielsen2848]

i agree these test are so misleading as they can be. she should remove this video asap.

[@joshuablack2446]

She states at the start that she is discussing audio absorption not reflection, most people can't make a aur vacuum box around themselves to stop exterior noise pollution

[@francisking5164]

I have to agree with you beachton123, if you watch again you will see the girl's facial expression when she explains comments on the pink fiberglass.!

[@MrFree-vj8qj]

You are saying The 1mm kraft backing with zero mass made this big 40% difference ? the difference stands and the other ones dont have a kraft backing. In any case this test is not very useful because they tested a high pitch note, shouldve tested real loud bass.

[@mrjesseholt]

Her test does a fine job at showing how much sound the materials can absorb. If you are trying to stop a sound reflecting off a surface and coming back to you with an absorption panel, the panel is going to be placed in front of the reflective surface to absorb energy from the sound waves, then it will reflect off the wall and pass back through the panel, where even more energy will be absorbed.

[@cf5914]

What is amazing about rockwool, and why it is the preferred material in professional recording studio, is that it absorbs sound very evenly across the frequency range, even down to quite low frequencies.

[@MrFree-vj8qj]

The lows are the real problem they can even require sand and other heavy materials to stop, high freq are not even an issue.

[@johnhender]

I used rockwool for my atmos install in my condo The people upstair couldn't even tell I had in ceiling speakers

[@cf5914]

@ALJ Studios I have freelanced and been a staff engineer in some extremely high end studios designed by top names and in all of them they utilized sophisticated geometry with several layers of rockwool lining the walls of the control room with a permeable fabric covering it. I am unaware of a better setup.

[@shanemccann2915]

@@cf5914 cool, thank youfor sharing your experience and expertise. I feel like rocwool is such a cool concept in the same kind of way as it's just cool to think about the fact that airplanes and helicopters actually work.. they just sit on top of air from our point of view.. or the fact that the Netherlands holds the sea at bay. I think it's madness that we put rocks into essentially a badass cotton candy machine and it makes lava silly string that you can compare to wool... Have you heard of any studies into having it behind a breathable fabric? I know it was once called as dangerous as asbestos but I don't think it is. I guess if undisturbed it can't hurt too much but if not sealed very tightly I wonder if it ends up being inhaled at all. Surely singers etc would complain of their throat drying? Just wondering if you know.

[@cf5914]

@@shanemccann2915 I know of no issues with having the breathable fabric. These setups are now VERY standard in professional studios and have been for 15+ years.

[@thinkabout602]

Glad you have a good sponsor. I will keep that in mind when I need various types of insulation. Best of luck and keep going 💪

[@jimurrata6785]

Congratulations on your sponsor! I'm glad you are beginning to get the recognition you deserve for your very informative and unbiased reporting.

[@trevorrisley5419]

Another Belinda Carr video? HELL YEAH!!! It’s cool to see her evolution and to be here early-ish, before she eclipses 500k subscribers.

[@BelindaCarr]

Yikes, long way to go! Thanks, Trevor :)

[@ricoludovici2825]

I used fiberglass between bedrooms in a new house with 5/8 drywall and found it had almost no effect on ambient room noise: music, taking, moving around. I tried Safe n' Sound between two bedrooms in a second house with 5/8 drywall and found it had minimal, perhaps even less effect. Now I saw Scott MacGillivray on HGTV use Safe n' Sound and it cut the sound transmission between floors by about 95%. I'd like to watch that vid again. Of course, he used sound isolating metal channels on the rock for the ceiling. Classically, the only thing that damps sound has been MASS. Heavy stuff like concrete, masonry, concrete block and/or isolation of the silent space from the rest of the structure. This latest vid is quite interesting. I think I will use the isolating strips along with insulation of some kind on the next place.

[@RenKnight347]

Many of those garden variety acoustic sound panels have sand within them which can also be a good mass medium for making it more difficult for sounds or vibrations to travel through.

[@mikemcdonald5147]

congrats on the sponsor you deserve it. I know this is two years old but just found it. Ive seen other videos of yours as well. Smart and pretty lady. Thank you for all you do and sharing these videos.

[@darrencurry4429]

You seem to be measure audio transmission, but I thought sound panels were to prevent audio reflection.

[@fluffycritter]

Yeah, in a recording studio you have to cut down on both internal reflections (to improve recording audio quality) AND external transmission (to improve isolation with the outside). It's helpful to see how useless acoustic foam is regarding isolation, but only because there's a common misconception among a lot of people that acoustic foam improves isolation, which it clearly doesn't (nor is it meant to).

[@MrFree-vj8qj]

Fiberglass and mineral wool do both, but insulation way better

[@asianwoof]

Your tests are measuring sound transmission, but sound panels are designed to absorb sound. The two aren't exactly the same, which is why the kraft-faced fiberglass seemingly outperformed the mineral wool batts. The angular foam isn't used to reduce sound transmission; it's used to absorb some sound and reflect the rest in different angles so as to reduce/eliminate echo/reverb. If you were to build sound panels properly, you would use Owens Corning 703/705 series rigid fiberglass boards and use fabric specifically designed to allow sound to pass through it and hit the insulation rather than reflect it. Guilford of Maine is a primary supplier of such fabric. This is not cheap, so I can understand using batts and any kind of fabric. If you were to remodel a space or build a sound room to isolate from external sounds, you'd add mass-loaded vinyl in-between layers of gypsum wallboard to the usual wall construction. This, too, is not cheap, but if you were to do it right, this is how you'd do it.

[@BiroDani82]

I really like your videos but on this one I would mention 2 of my issues with it: 1: I would test these materials with different frequencies, not just one high pitch sound. Probably all materials will show different characteristics through the audible frequency range. 2. The fiberglass won because it has that paper backing on one side of it and that helps a lot on high frequency. Apart of these small issues, I really hope that you will carry on and make more and more short but educational videos! Good luck with them! Dan

[@briansransom]

So the best insulator would be paper then.

[@juangalbaladejo6866]

@@briansransom no, it's the best reflector to reflect back to the phone the test tone that is 1kHz. It is not testing the absortion capabilty for reverb of 50ms or less of a 1kHz tone in this case.

[@fauxnom2945]

With respect, your test may be flawed. The video shows that the fiberglass has a backing on it which should have reflected a great deal of sound back towards the emission point. The other materials did not have that. It would be interesting to see whether the results are the same when all materials don't have a backing. My hypothesis is that it will change the results significantly. Also, using backed insulation then creates an issue for panel design. A panel using insulation with backing should place the backing on the wall side of the panel. Aside from the test methodology topic, you could expand on the topic of acoustic room treatment in the future by discussing panel designs which unevenly disperse the sound waves which are not absorbed. A big part of acoustic room treatment is reducing the magnitude of reflections coming from a specific direction and in randomizing the reflections.

[@sinisterdesign]

This is really interesting! I think your test may be held back a little by the fact you only tested a single tone, however, as different materials tend to do a better job dampening sound at different frequencies. I'd be interested to see a follow-up!

[@jesinu]

Ohh, yes, I am now curious about this too! We need a full spectrum sweep!

[@jordanmiles8615]

@@jesinu exactly I need t know how it does with frequencies below 200hz

[@matukaz]

Also if possible, make a video of sound panels with different insulation and test it in same room and how it will affect the room sound charateristics?

[@BelindaCarr]

I tested different frequencies after making this video and got the same results. I hope to build a small room/testing facility in the future to perform more tests!

[@narmale]

should use white noise

[@douglasascencio9140]

Congratulations on the sponsorship. Been watching your videos on storage units used as houses, glad to see you are growing more and more the potential of the channel, cheers :)

[@BenjaminGib]

I have been studying home DIY sound panels for MONTHS! Thank you for this best video!!

[@peterlopinto]

Part of what sound panels are designed to do is reduce reflections of sound coming from within the room. So while it's important to be aware of how well your materials reduce noise coming from outside, part of the benefit of acoustic foam is that its shape and material are designed to reduce reverb. Perhaps there's a type of test that could be designed where you make a loud noise and then test how quickly the sound dissipates. I'd be really interested in a video like that! I work with people who create home setups for dialogue recording, and often we find that closets are a great natural space due to the absorption properties of just clothes!

[@ezequiel5260]

Congratulations on your first sponsor!!!

[@deadcells963]

Honestly I’ve never been interested in these type of things , but you have such a nice voice and you come across as very educated and knowledgeable 😭 So glad I found this channel

[@azarellediaz4892]

Simple, short and to the point… the best video I’ve seen so far about DIY sound dampening. Thanks.

[@jimurrata6785]

I'm thinking that most people that want "panels" are looking to reduce reverberation (echo) in a room, to make it sound less like a gymnasium or bathroom. In a case like that you want a low density with almost anything but a flat surface. Look at those anechoic chambers. Their baffling is the audio frequency equivalent of radar absorbent 'stealth' coatings. Exposed egg crate foam would probably help the most in creating a 'dead' room. Often if using flat panels just having them off axis is going to work better than being 'normal' (perpendicular) to the sound source. *Something like a sheet of mass damping in the back of them will stop transmission all the way through and drink up a lot of whatever pressure waves _do_ make it through your primary line of defense.

[@nefariousyawn]

Congrats on the sponsorship! Have you seen any of the channel Tech Ingredients' videos on sound isolation? I was also surprised by your results with fiberglass.

[@BelindaCarr]

Thanks, Tucker! No, I haven't, but I'm going to check out his channel now.

[@kameljoe21]

I was just trying to find that video.. There were a couple over the last couple of years and this was the one I found so far.. i think it was the one where he did the speakers and the type of insulation in them... kzbin.info/www/bejne/oJu9eXl_mcuIfM0 ​ @Belinda Carr

[@kameljoe21]

​@@BelindaCarr was just trying to find that video.. There were a couple over the last couple of years and this was the one I found so far.. i think it was the one where he did the speakers and the type of insulation in them... kzbin.info/www/bejne/oJu9eXl_mcuIfM0 ​

[@arsaeterna4285]

AWESOME : ) love all your videos, your calm, respectful speech is exactly the language I need

[@ryanwalsh6821]

I would be curious to see how the decibel drops at different tones, especially the lowest tones in the 40hz-250hz range. From my understanding certain materials are good at the mid-high frequencies but can't absorb the pressure waves of sound as it dips into the lower range. Great video as always!

for lower ranges you need mass (so heavy open-celled insulation). But its only for correction. If you want to avoid annoying your neighbor those panels wont hep a bit.

[@tim_tim_tim]

I really like this woman and her ideas

[@knowitall1694]

Sound doesn't just come in different frequencies but can be transmitted in different ways. I used to have a neighbour who liked to turn up his stereo. He lived 75m away. Although I couldn't hear the actual music, I could hear the sub-woofer bass pounding. It went through his concrete slab into the clay soil which transmitted the sound 75m to my house and my concrete slab in turn also vibrated. That is why drums and bass guitar in a studio are often placed on a mini stage that has springs, rubber and other vibration absorbing features.

[@luckycatdad8369]

As others have mentioned, Rockwool should be better at absorbing in the lower frequency range. It has about twice the density of fiberglass. Interesting test results. Would like to see the lower mid tones and bass tones tested.

[@hydrusje]

It is well known that mineral wool like rockwool is one of the best sound dampening materials. (not insulation, dampening) It is open enough for air pressure to move through it and heavy enough to dampen it, converting it into heat. The thicker the mineral wool, the lower the frequency it is effective at. Rule of thumb is to use 1/4 of the lowest wavelength you want to dampen.

[@Nightowl427272]

Yep, especially at low frequencies. The hardest frequencies to combat in bedroom studios are the low frequencies.

[@victorhex6380]

Somehow you take building items we don't give much consideration to and make a very cool, excellent and easy to understand class on the subject. On a side note, we are building a camping van and are now getting ready to insulate it. Thanks!

[@NuMooX]

Congrats on the sponsor! Your hard work and unbiased reviews paid off, and hope it continues.

[@Krazie-Ivan]

disappointed my 2 fav methods didn't make it into your tests. MLV is worth looking at, esp for low frequencies & keeping sound within a room. and the cheapest option (old towels), is hard to beat for lowering in-room resonance of mid/high tones.

[@tonyhemingway7980]

Carpet remnants work well, also.

[@Krazie-Ivan]

@@tonyhemingway7980 ...good tip, thx

[@JohnSmith-kf1fc]

Congrats for your first sponsor! They made a smart choice to partner with you because you will grow big with this channel. All the best :)

[@starborned]

I know this is an old video but I just gotta say, I play guitar and drums, and I'm in the process of creating a recording space. I also work construction and it's always interesting to me just how much the sound in a room becomes isolated (not completely isolated, before all the know-it-alls crucify me) when you speak in it, not to mention all the noise and power tools. And of course depending on the R-value this can increase or decrease. Anyway she does a great job, and a DIY'er at that! Awesome video!

[@SinnisjInsulator]

Fantastic work Belinda. It would be very interesting to share a graph of how each insulation did with various frequencies.

[@johnjames5020]

fiberglass panels for my home theater it is. Thanks Belinda!!!

[@FJB2020]

AVS covers this in depth.. Fiberglass works better. Double layers of 5/8" drywall with green glue, fiberglass and channel works wonders.

[@americatunedright1211]

Thank you for the video. Fiberglass is so much more easier to get. I’ll be building my panels and using fiberglass for my acoustic issues.

[@roontunes]

Thank you 🙏 you're a legend, worth sitting through the sponsored video

[@stevesmith1493]

We use R30+ designed for 2x6 walls but in 2x4 wall depth. We also use 5/8 thick Sheetrock. Gets down into the low 60s and high 50s. Very effective for the $$

[@jonwikan3986]

Yes, a good test for DB reduction, at one particular frequency at one particular point but most sound panels are primarily trying to stop annoying standing waves in a room that cause kind of, and sometimes very annoying reverb. In studios we can also make traps that are deeper in size or less deep to trap certain target frequencies. I think Mineral wool is more desirable, it is used in fire assemblies and won't burn like fiberglass does, it is water resistant, mineral wool can be expelled from the lungs and it does a slightly better job in the low end, otherwise the professional ratings are fairly close. For me I use mineral wool because it is widely available in low or really high density batts and panels and of course it is basically fireproof. The 703 fiberglass acoustic insulation is very expensive and I have to have them shipped. Here in NY I can hit my least favorite store Home Depot and get 1.5" 24x48 rockwool comfort board and double up or triple up depending on how low of frequencies I want to absorb and make pretty large panels that really work! . Comfort board is very stiff and dense doesn't even need a wood frame, although I use a frame so fastening fabric is easier. Or one can stick with batts that are smaller, less dense and need a frame. I think when testing one should compare products with the same density as well, so you are not comparing apples and oranges.

[@Stelios.Posantzis]

Doing a sound absorption comparison of insulating materials is a great idea. I'd be interested to see more. In particular, the distinction made at the start between noise and other sound such as music, speech, loud bangs and thuds, motor hum or engine drone is very significant and worth expanding on, I believe. It'd be great to see the performance of each material judged on more than one frequency and type of sound as well as different levels of loudness. I'd also like for the thickness of the material used in each experiment to be more clearly stated. I like the experimental set-up as it is simple and reproducible by anyone and also avoids sound transmission via supporting structures e.g. wooden frames and panels or plasterboard etc. which are the main culprits for sound transmission through walls, ceilings etc.

[@ustmissouri8029]

Forget all the other stuff. Super Cute!!!!

[@cmaedjr3358]

Exactly the video I was looking for

[@Exploitiv]

We love you Belinda!!

[@Exploitiv]

All your KZbin ideas and videos are sound and intelligent. Let those haters hate, is true fans love your content.

[@b22chris]

Great video! I’m going to insulate my basement ceiling to help with sound proofing!

[@ScooterFXRS]

L0L ... unlike many that butt a corner of a brace into a corner, this smart person leaves the corner open for stronger bracing. Well done. Great topic.

[@jek__]

lol "remember cinemas?" Useful information that is well presented, subscribed after one video

[@vociferonheraldofthewinter2284]

We had our house custom built a few years ago and I had to add a twist that the builder was shocked by. Our house is built in three primary sections (master suite, primary living area, offices/extra bedrooms) and I wanted the walls between the zones heavily insulated with fiberglass. I had to pay extra for it, but I got my way. The benefit? Each zone is sound isolated from the others. Meaning hubs can go to bed and I can stay up and watch a movie with the home theater system without him hearing a peep. He can get up and bang around in the kitchen without worrying about bothering me. That six inches of fiberglass works SO WELL. The only down side is that we do a LOT of "WHAT?! I can't hear you!" and "Honey? HONEY?!! WHERE ARE YOU?!!" and "DID YOU SAY SOMETHING?!!" "I'M IN THE LAUNDRY ROOM!!!!!! HEY!! *HAAAAAAY!! I'M IN HERE!!!*"

[@CamiloVelandia]

Thank you Belinda!

[@JordanWorkshop]

Thanks for a great test! I wonder if the rockwool does better on lower frequencies. As far as sound blocking, the lower frequencies seem more difficult to dissipate. Possibly a frequency blocking comparison?

[@Lolatyou332]

Yes, rockwool is better on lower frequencies. there are data sheets that show the differences between sound dampening between different insulators at different frequencies.

[@essmene]

While researching sound stuff for my workshop I ran across an acustian(?) and he said you need to differentiate between sound insulation (Schalldämmung ) and sound absorbtion (Schalldämpfung). Sound Insulation being the ability to shield your neighbor from your noise generation. And the main ingredient is Mass, mass, mass. And disconnecting sound generators from hard surfaces. sound absorption on the other hand describes the amount of sound energy reflected by the surface back into the room, creating hall effects and noise. Sound absorption may reduce the noise in the room, but your neighbor will not notice any difference. I think this distinction is important as some people may want insulation and buy absorption.

[@CreativeEye1]

I enjoyed your video very much. I found yours more informative than others that I've watch. Dealing with DIY sound panels. Thanks!

[@Trading-mp5jp]

The way you said this is my first promotion video ❤❤

[@p.a.l3795]

I found the same when I did the reno for an apartment in my basement. I'm afraid I spent a pile of money on the Rockwool Safe and Sound product when I probably would have acquired the same or better result using fibre glass. I used resilient channel, 2 layers of Safe and Sound, 2 layers of ⅝ sheet rock and green glue on the edge seams. I chose not to use the green glue between sheets of drywall because of the cost. It definitely made it quieter but not worth the expense if I was to do it again. Another thing that was frustrating about the Safe and Sound product was the top and bottom batts were so compressed from packaging that they weren't very useful. Since there are 8 batts in a bundle, that meant that roughly 25% of the product didn't work. Lesson learned. Thanks for the great videos.

[@BelindaCarr]

That's a very good point. It much more difficult to fluff up rock wool compared to fiberglass... I can't believe I'm actually advocating for fiberglass lol!

[@p.a.l3795]

@@BelindaCarr ha ya. All things considered, I think fibreglass with the 2 layers of ⅝ sheet rock would have been the way to go. I'm even thinking the resilient channel is a little over hyped. When I inspected the finished product, it didn't hang like I expected. There was plenty of channel contact to the joists for sound transmission. I'm thinking now that I should have listened to some early utube advice where they said for what little extra sound proofing you get from all these steps, it's not worth the huge extra cost. Their recommendation was the fibreglass between the joists and 2 layers of ⅝ sheet rock. Hope this might help someone.

[@FJB2020]

Soundproofing is tricky. The next time you do this pack the stud bays with as much unfaced fiberglass bat as you can, run 1x3s pependicular to your studs and hang 5/8" OSB in the middle of the 1x3 span, then put two loads of green glue on the back of a sheet of 5/8" type x drywall and screw that with short screws into the OSB. Make sure you caulk all joints on both the OSB and Drywall with acustic caulk. This is how I build theater rooms and it does a great job dampening noise.

[@juiliethakur37]

Glad I found this. I made my own from household waste:cloth and cardboard, because, "no money". Will upgrade later... But most people working on insulation have said Rockwool passes the fire test better than any of the other materials that are currently used.

[@mjdedge3440]

1st sponsored video!!!! Well done you :-)

[@davidjoseph67]

The effect of placing panels to absorb sound is to lower the reverberation coefficient in the room. Proper test equipment is needed to show how quickly a loud sound (about 100dB of white noise) returns to normal dB levels once the source is switched off. Then panels are placed to “treat” the room and the test is performed again. Treating the reflective surfaces in the correct location will demonstrate a reduction in reverb coefficients in large rooms from 4-5 seconds down to an optimal number of about 1.2-2.0 (depending on the intended use of the space). Your test is interesting- yet only really proves that we are already using the right insulating material to keep unwanted noise out of our homes.

[@vaschnisavain9983]

Congrats on the Sponsorship!

[@frijoli9579]

I'm glad someone else brought up different frequencies as well. This is a huge factor in choosing panels for sound deadening, or dampening reflections, bass trapping etc. Your test method while interesting misses a lot of important factors. You CANNOT use a phone to test real sound properties.

[@AndrewGilpatric662]

Thank you for caring a sponsor I was looking for a cheaper alternative to buy my insulation and the big box stores thank you thank you 😘

[@teresacoffman5529]

Acoustics and architecture! Two of my favorite subjects!

[@Bang-C4]

Glad to hear that you are getting sponsored, I enjoy your channel. I was surprised at the results you got with fiberglass. I've always been under the understanding that it did a worse job than the others at blocking sound. I am a little disappointed that you only tried one frequency. I always look forward to your next video keep up the good work.

[@BelindaCarr]

I tested other frequencies, after making this video, since many people commented on it. Surprisingly, I got the same result! Never thought I'd lean towards fiberglass lol.

[@Bang-C4]

Thank you for your reply I appreciate it. And for going to the trouble to rerun your test at different frequencies. The results surprised me and I appreciate your efforts.

[@LacroixCruiser]

Thank you, great video, and congratulations on your sponsorship.

[@TheShornak]

Hello Belinda, very interesting video on the sound panels. I was really surprised about the fiberglass material being the most effective. I would have thought something more dense would have been better. Congratulation on your sponsorship also. Take care. 🙂

[@LiviuGelea]

I'm sure you'll get a lot of comments about this, but 19 seconds into the video and I already heard "sound insulation" twice. Sound insulation means preventing sound from going through a medium. Sound treatment means preventing sound from being reflected back to the microphone, thus improving the quality of recordings. Studios require sound treatment. It's the neighbors who want sound insulation

[@LiviuGelea]

Sound panels are meant to prevent reflections. it's why they're usually only ever used partially in walls, to allow for "some" reflections back to the mic making the sound not completely dry to the point it sounds unnatural and require reverb to be added in post-processing.

[@KellyMillerGerlach]

Putting together a sound studio, this video was very helpful...Thankyou!

[@konagolden3397]

Much of what you do is very good work. I think your understanding of sound and the different treatments, where, why and how used is open to improvement. For anyone, a working understanding of decibels, amplitude, frequency, sound dispersion, room shapes and standing waves is imperative. The difference between sound blocking, dispersion and absorption along with decoupling sound transmitters (walls, floors, etc.) is important. Low energy high frequencies are easier to attenuate than high energy low frequencies. Standing waves create huge issues with sound. Identifying the goal, the problem areas, and then the possible solutions may be a better approach to choosing what materials to use, where, and how. Don't stop doing what you do, just continually learn and improve.

[@indijen]

This was so helpful, thank you! We are just about to insulate a wall for thermal and noise issues, and now I am excited that fiberglass can do both well!!

[@daviddorge1559]

I always hit the like button every time I hear you say video. No one says it better

[@joshua43214]

Hi Belinda, As I am sure you have gathered from the other comments, you might want to return to this topic again. As you said, it is a very complex science. An important part of the science is that different materials absorb differently at different frequencies. The test tone you used is not a realistic test because the frequency is far too high. For sound panel testing, you will need to perform the tests outside or in an extremely large room (more than the quarter wave distance from each wall). You can easily cobble together a speaker (make sure you get a full range driver), and use Room EQ Wizard to perform the analysis (freeware). Driver and microphone will set you back well under $200.00 and probably under $100.00 if you go cheap.

[@catman8965]

Quick and to the point. THANKS

[@Jonathan_Frame]

You're awesome! Thank you so much for doing all the hard work and documenting it for us. I'm on my way to the hardware store to get some fiberglass insulation.

[@InssiAjaton]

There are a myriad of issues related to the room acoustics. One of course is do you need to attenuate noise from the outside. Then you need attenuation in the walls (and floor & ceiling). That is achieved by something like very heavy construction, say brick or medieval stone walls. Alternatively, you can stack different layers and depend on acoustic impedance variation. The reflections at each different interface can consume the acoustic energy and produce attenuation. On the other hand, the room acoustics is generally an echo phenomenon. In the ancient churches and a few concert halls, they built some cavities in the walls to resonate on the dominant echo frequencies. They tuned the frequency and attenuation by adding varying amounts of sand in those cavities. Modern concert halls use the hall geometry, as well as padded seats. The worst geometries would include a full sphere or a cube. Any changes from the cube to for example tilted ceiling are good. When that often is out of question, as an afterthought, you need to add absorbing materials in different locations. The first and most obvious option is a floor carpet. Bookshelves (full of books!) and various furniture follow and wall rugs etc. are then the last remedies. We once made our campus studio that was miserably close to a cube shape to usable space by plastering the walls with 6 by 6 egg cartons. When the studio was moved to a new building with properly designed and built room, the people who had to restore the original room were not too happy about our egg cartons, but that is another story... Professional acoustics designers used to start their improvement efforts by measuring the room echo decay after a "clapp" or even a start pistol shot. Based on the decay time constant, they presented their recommendations. I once had to improvise a similar measurement (without a clapp machine or a pistol). I used a gated signal to a speaker as an impulse, and a microphone with a tape recorder. I made several recordings and then cut the tape into pieces, which I formed into continuous loops, one impulse per loop. Then I analyzed the frequency and amplitude characteristics with some self made electronics. The results were OK and improved further when we moved all our laboratory equipment in. That was not a studio purpose, of course.

[@LordRa777]

This was very useful keep making videos you sid a great job

[@OisinHiggins]

Congratulations on sponsorship, well earned. Did you test the absorption at any other frequencies? Was there a reason you chose to test at that frequency?

[@BelindaCarr]

I tested other frequencies, after making this video, since many people commented on it. Surprisingly, I got the same result!

[@ejbragg1]

Hi, thanks for doing this comparison. I noticed that you left the paper backing on the fiberglas insulation; none of the other insulation types had paper backing. My guess is that if you remove that backing, at the frequency you measured, the rockwool might have won the contest. At higher frequencies, thin barriers like paper are more effective at blocking sound. The fiberglass, foam, and denim are not considered barriers, but absorbers (obviously). But anything like a membrane with no openings is usually regarded as a barrier - except to low frequencies (wavelength compared to barrier thickness is the factor). But thanks again for your work. Simple fiberglas does indeed perform rather well, and in some cases, better than rock wool.

[@billwilliamson1908]

thx for doing this comparison. Donnacona board also claims to be a noise reducer. It may be same as Celotex. It would be nice if you could test this out. Btw, you are my favorite KZbinr right now.

[@WarrenPostma]

My new favorite youtube channel. Well done. You are doing a wonderful job.

[@RealDavidN]

If you're using sound panels to absorb sound echoing around in the room, be aware that this is not how they are tested. What she's measuring is sound transmission, not sound absorption. These are two completely separate functions. Ironically, you could cover the box with a layer of concrete and the levels would drop even more. But concrete absorbs almost no sound compared to any of these materials. What you want to measure is the sound reflecting (or not reflecting) off the surface. A more meaningful homebrew test would have a reflection off the absorbing material be the only path from the source to the sound level meter. It's actually kind of tricky. And yes, the answer is different at different frequencies.

[@1xm_mx1]

Congrats on getting sponsorship!

[@Crazson34]

When I'm working overseas building a "secure" room, we go by STC ratings (Sound Transmission Class) and we have totally different ways of achieving that but I can tell you one thing, a marching band could be on the other side of the wall and you wouldn't hear it. FEBR doors and windows also complete the task but not many people are installing those unless they've got big bucks are might become a target.

[@leonardkellum6984]

i used rockwool, thanks for this.

[@b1j]

What we care about in home audio production is absorption across as much of the audible range of frequencies as possible. You are correct that absorption decreases in the lower frequencies (bass). You tell us the dB or sound pressure level of the emitted sound from your emitter, but I didn’t catch any mention of the frequency. We need absorption data measured vs. frequency from 20 Hz to 20 kHz. You seem to be someone who could either perform this testing, or provide a learned review of available data. This would be more meaningful than stuff in a cardboard box.

[@mochen665]

Thank you for the video, found it very useful and educational

[@hunterchasens835]

You may have fallen for the classic acoustic pannel trap! I'm new to the topic (so I might be wrong) but from the research I've done there's a difference in absorbsion and blocking. For example, concrete is very good at blocking sound but reflects it. If you were to submerge your phone in concrete, let it dry, then produce the sound, it'd be almost impossible to hear, but you wouldn't want your sound pannels made from it. The property we want in acoustic pannels is sound absorbsion since we only care about sound reflecting back to us. From what I've read fiberglass is actually worse for sound absorbsoin than both rockwool and denim but better at blocking. There's a special program to determine the sound reverberation of a room. LTT does a video using this process. Again, I'm very new to the topic so I might be wrong. LTT's video: kzbin.info/www/bejne/iaDanJxng8SMm7s The Acustic Pannel Trap: kzbin.info/www/bejne/fqjEi5uKlKilj6s

[@qno-oj3py]

Hi Belinda, when making sound panels you should have measured reflection of the panel iso how much sound goes thru it.

[@chrisose]

The foam is only effective at dispersing reflected sound waves and as your test showed has little effect on pass through waves. The integral vapor barrier on the fiberglass batts would have produced the drop you saw in your 1khz sine wave test tone. Being more dense than fiberglass, the rockwool will be more effective in the low and low-mid frequency ranges. I have built a couple of mobile recording booths which typically give me a 20-25dB damping. These consist of a layer of 1/2" MDF on the exterior, a layer of 1/2" homasote board, a layer of egg-crate foam and a covering of acoustically transparent fabric to create a finish layer. Being very dense, the MDF reduces the energy transmission from outside sources. An 1/8" air gap and the homasote further dampen any sounds that do make it through the MDF. The egg-crate foam is a much cheaper alternative to the commercially available acoustic panels but is just as effective an damping the mid and high frequency reflections inside the booth. It is important to use an acoustically transparent material to close up the panels because any sound wave that cannot pass through it will be reflected, effectively acting much like a solid surface. In the above instances the only reason I didn't use rockwool was because it would have forced my wall thickness to 6 inches. As it was I was able to keep the wall panels to a 3 inch thickness.

[@craigenputtock]

Wow you're really talented. I couldn't do that.

[@TheGamefreakr]

NOTE FROM PROFESSIONAL SOUND ENGENIEER: Please note that this method only test the materials sound suppressing/insulating properties and NOT the absorption coefficient nor the refractory index of it. That taken into account - Nice short video, not really any other stuff raising flags. Best Regards

[@chrisforker7487]

Great video, congrats on the sponsorship!

[@kaiwenhe5518]

Congratulations, you have been doing good job and I hope there are more companies come to you for business.

[@terrylutke]

Once toured an Armstrong Cork facility which included a walk-in anechoic chamber. Armstrong was no fan of the pink stuff but here the chamber walls and ceiling were lined with fiberglass insulation in the shape of pointy cones. This room was almost acoustically dead. The sound energy soaked into the fibers & dissipated with no return potential. Sound transmission between rooms is a different animal; good sound walls require some combo of sound energy absorption, rigidity, density or mass. Example..Stud walls lack mass and rigidity and thus tend to be poor sound isolators. A stud wall covered with lead lined wall board performs much better due to the added mass of the thin lead sheet. Concrete and masonry tend to be great at killing sound transmission, almost entirely due to mass. Room shape also plays large in dissipating sound; sound energy loves boxes with 90deg corners or perfect silos since there is little to confuse or defuse sound energy patterns. Automotive mufflers are a great study concerning damping using only sound wave confusion (pattern breaking).

[@ntuthuzelopakade2583]

Very insightful video with real-life demonstration.

[@kojam1]

GREAT VIDEO!!! My only critique is that we never got to see/witness/hear your final project. I was sitting on the edge of my seat, with a bunch of popcorn, waiting to see what happened....then.. * poof * Nada! Is there a part #2 coming? I was trying to see EXACTLY which fibreglass you're using. Wanna check my local homedepot here in Canada for it.

[@Thenextme.]

Thank you for the great video and the curve

[@practicallysocial]

A 6db spl attenuation is a noticable difference from an audio engineering perspective, regardless of the rest of of the criticism. What a lot of people tend to forget is that creating contours and additional air spaces will also disturb the sound wave and "break it up" more. This is why you see countours and "shaping" of panels in high end studios and halls.

[@jerryngobese3216]

Wow thank you for standing up for once and doing some real engineering work.... the info you give is valuable let's see you doing it more than lecturing, thanks for moving around the info is highly appreciated ... so are you. More demo's please, let's see you moving and showing us stuff ... it's not a lecture it's a vlog

[@ReasonablleDoubt]

Doing a project right now with sound insulation. Great video

[@gtamediaproductions1]

Wow you are very knowledgeable about giving DIY information! I am purchasing a sound meter for this purpose but looking for the right one that will cover all bases. The main issue I have right now is that the room that my off is in is a good sized area but oddly shaped structure for sound balancing. So it becomes quite a challenge to get it just right for my liking. I will consider the fiberglass insulation for sound panels and take the safety precautions while building them. Always do. Thank you so much! ✌🏻

[@milkman100001]

next time i need some panels ill give you a shout.you made up those panel frames better than mine.lol thanks for the tests

[@anfernyjackson9013]

Hi Belinda, I commented on the video that was linked after reading that Canadian study, NR 761. It actually says mineral wool (Rockwool) actually performed slightly better than fiber glass insulation when it came to wood stud construction. Not sure why it's the opposite here

[@sepehrabdar9304]

respects for the knowledge, congrats on your first sponsored vid hope you got bare after that, i know this was 2 years ago