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Another acoustic traps thickness question. Sorry.
Old 3 weeks ago
  #1
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Another acoustic traps thickness question. Sorry.

I’m going to ask a question that’s probably the most popular thread question. And I’ve read several threads in the subject. I’m trying to get more clarity and newer information. I’m thick. Sometimes I’m just not understanding the answers given in these threads. I’m building a piano room. Converting a garage. And because of mold and asbestos abatement I’m having to redo the entire studio. In the past I used 4” OC 703 or Knauf ECO with a 2” gap. I thought it worked very well. I hung these as 2x4 panels of French cleats and as clouds over the drums and in the CR over the operator. Me. Otherwise I had GIK corner traps, floor almost to ceiling. It’s a cottage. Not square for the most part. I can’t put ghe traps in every corner.

Now it seems OC 703 is no longer thought of highly. And pink and fluffy is considered superior for absorbing lower frequencies? 4” with 2-4” isn’t good either? Or am I misunderstanding the favored 8” minimum by Avare? I’d that 8” TOTAL depth? Meaning it could be 4” of fiberglass and 4” gap? But 9” of Safe n Sound with no gap is as good as 4” of R-38, or knauf whatever? Lol. Sorry. I’m not a math person and not at analytical.

My plan is to put 6” with 2” gap of safe n Sound or something as clouds over the piano and throughout. It’s a tracking room, not a mixing room.
Old 3 weeks ago
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What is your question? 703 has changed, Different materials are used at different thicknesses.
Old 3 weeks ago | Show parent
  #3
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Quote:
Originally Posted by avare ➡️
What is your question? 703 has changed, Different materials are used at different thicknesses.
Ah! The question got lost in the set up! I don’t understand 8” of fiberglass or 8” total distance from wall. Is it 6” fiber plus 2” gap? 4” plus 4”? It 8” of pink fluffy or safe n sound? And R-38 is best for lower frequency absorption? Would it be best to mix two kinds of boards, ceiling, lower wall, mid wall?
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  #4
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Quote:
Originally Posted by henryrobinett ➡️
Ah! The question got lost in the set up! I don’t understand 8” of fiberglass or 8” total distance from wall. Is it 6” fiber plus 2” gap? 4” plus 4”? It 8” of pink fluffy or safe n sound? And R-38 is best for lower frequency absorption? Would it be best to mix two kinds of boards, ceiling, lower wall, mid wall?
If you have read here for a while then you have read about peoplpe using thin absorbers for the the walls and ceiling, getting a "good" sound and then adding bass raps and then complaining about a "dead" high end. They have imbalanced the absorption. With wave theory 8" depth provides good absorption in normal incidence to ~300 Hz and ~150 Hz in random incidence. Names are not useful. Gas Flow Resistivity (GFR) numbers are.
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  #5
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Quote:
Originally Posted by avare ➡️
If you have read here for a while then you have read about peoplpe using thin absorbers for the the walls and ceiling, getting a "good" sound and then adding bass raps and then complaining about a "dead" high end. They have imbalanced the absorption. With wave theory 8" depth provides good absorption in normal incidence to ~300 Hz and ~150 Hz in random incidence. Names are not useful. Gas Flow Resistivity (GFR) numbers are.
OK. Good. I think that makes sense. What about my question about 8” fiber or is that 8” fiber plus gap? Can you see where I’m confused? I had thought originally you were talking about 8” of pink and fluffy and THEN an air gap.
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  #6
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Quote:
Originally Posted by henryrobinett ➡️
OK. Good. I think that makes sense. What about my question about 8” fiber or is that 8” fiber plus gap? Can you see where I’m confused? I had thought originally you were talking about 8” of pink and fluffy and THEN an air gap.
What is your question? In order of increasing absorption:

8" of appropriate insulation
8" of appropriate insulation plus 2" gap
10" of appropriate insulation

Here appropriate insulation is "pink and fluffy" with a GFR of 5,000 Rayls/metre.
Old 3 weeks ago | Show parent
  #7
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Quote:
Originally Posted by avare ➡️
What is your question? In order of increasing absorption:

8" of appropriate insulation
8" of appropriate insulation plus 2" gap
10" of appropriate insulation

Here appropriate insulation is "pink and fluffy" with a GFR of 5,000 Rayls/metre.
Thank you Avare! It looks like I'm cross posting to two different threads I created. Sorry about that. I'm trying to get started ASAP here. I've got to decide on the type and brand of fiberglass insulation. Either OC 703, which I know has fallen into disfavor because they changed, SnS or OC or Rockwool or knauf R-38. I'm assuming R-38 is more common and cheaper. Is that the pink and fluffy stuff?

I posted in my other thread that there's a local supplier who has a ton of OC 703. I think hes ad it for many years, so I think the stuff he has is BEFORE they changed. Would that make a difference? Also it looks like there's a place 150 miles away that has SnS 6". I don't mind making the drive. I got nothing else to do while the abatement team finishes.
Old 3 weeks ago | Show parent
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Quote:
Originally Posted by henryrobinett ➡️
Thank you Avare! It looks like I'm cross posting to two different threads I created. Sorry about that. I'm trying to get started ASAP here. I've got to decide on the type and brand of fiberglass insulation. Either OC 703, which I know has fallen into disfavor because they changed, SnS or OC or Rockwool or knauf R-38. I'm assuming R-38 is more common and cheaper. Is that the pink and fluffy stuff?

I posted in my other thread that there's a local supplier who has a ton of OC 703. I think hes ad it for many years, so I think the stuff he has is BEFORE they changed. Would that make a difference? Also it looks like there's a place 150 miles away that has SnS 6". I don't mind making the drive. I got nothing else to do while the abatement team finishes.
Read this:
https://www.jochenschulz.me/en/blog/...orber-material

8" of the correct material with the flow resistivity is the minimum for Broadband Panels.
You have some absorption even down to 63hz (.5)


4" is only really useful if you are looking for controlling reflections in the listening area from 250hz-10khz, which in some circumstances is a need depending on the design and chosen treatment for the entire space.

Also unless you've been tracking the formulations of OC 703 consistently since the 90's , its impossible to know what year they changed it.
Why take that chance?

If you want to use 4" panels in the first reflection area go with Rockboard 40.

If you need 8" broadband absorption, look for Thermafiber SAFB( sound attenuation fire Blankets) which are easier to mount and stack together if you are doing the entire walls and ceiling.
https://www.owenscorning.com/en-us/i...n-fire-blanket

But make sure its not the Thermafiber Fire and sound blanket which has a different flow resistivity;
https://www.owenscorning.com/en-us/i...nd-sound-guard
Old 3 weeks ago
  #9
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Quote:
Originally Posted by henryrobinett ➡️
Or am I misunderstanding the favored 8” minimum by Avare? I’d that 8” TOTAL depth? Meaning it could be 4” of fiberglass and 4” gap? But 9” of Safe n Sound with no gap is as good as 4” of R-38, or knauf whatever? Lol. Sorry. I’m not a math person and not at analytical.
That's a "minimum" not a target. In my opinion the minimum is 12 inches.

There's no such thing as 4" of R-38. R-38 is a way of saying 12 inches.


Us the room absorber calculator. Knauf R-38 is 5,000. Compare it to anything you can come up with in terms of other material and air gaps and I think you'll have a hard time finding a way to beat it, and certainly not at the same price.

The extra depth isn't as big a deal as people imagine it.

According to GIK, who I believe is correct, you can compress it a little without changing the performance.
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  #10
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Quote:
Originally Posted by henryrobinett ➡️

I posted in my other thread that there's a local supplier who has a ton of OC 703. I think hes ad it for many years, so I think the stuff he has is BEFORE they changed. Would that make a difference? Also it looks like there's a place 150 miles away that has SnS 6". I don't mind making the drive. I got nothing else to do while the abatement team finishes.
Vintage always sounds better, right?

OC 703 was and still is different from fluffy with a GFR of 5k.

If you spend the same money on Knauf R-38 as you do on OC 703, you'll get better results with the R-38.

You could literally stand it on end and lean it against the wall and beat the what most people achieve spending all sorts of time and money building panels.
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  #11
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Quote:
Originally Posted by Mike Caffrey ➡️
That's a "minimum" not a target. In my opinion the minimum is 12 inches.

There's no such thing as 4" of R-38. R-38 is a way of saying 12 inches.


Us the room absorber calculator. Knauf R-38 is 5,000. Compare it to anything you can come up with in terms of other material and air gaps and I think you'll have a hard time finding a way to beat it, and certainly not at the same price.

The extra depth isn't as big a deal as people imagine it.

According to GIK, who I believe is correct, you can compress it a little without changing the performance.
Thank you. But I think 12” is huge. Certainly twice as large as I was considering. But yeah. Under consideration.
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  #12
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Quote:
Originally Posted by henryrobinett ➡️
Thank you. But I think 12” is huge. Certainly twice as large as I was considering. But yeah. Under consideration.
Avre and I have similar opinions, though I'm more conservative in that my minimum is 12 inches of 5k GFR and his is 8 inches.

I don't know whether he does any mixing, but I do and I think that anything under the minimum is the same as nothing at all. One might argue it's worse because you've now got tangible evidence to support the lie you're telling yourself about the accuracy of your room.

It's so easy if you don't get hung up over a few inches of room space.

Ultimately, what's the point of doing it if you're not going to do it right?

That's what I don't get about OC 70X and slats and all of the layers of band aids people add to their cut corners.

And it's cheaper to do it the optimal way too.

I just posted a waterfall in a thread here of a 9x12x9 room and set up the short way that's +/-3 db down to 15hz. And most of the frequency spectrum is better than that.

But I prioritized results over 4-6 inches on each side of the room.

I'm sure you'll do what's right for you.
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  #13
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Quote:
Originally Posted by Mike Caffrey ➡️
I don't know whether he does any mixing, but I do and I think that anything under the minimum is the same as nothing at all. One might argue it's worse because you've now got tangible evidence to support the lie you're telling yourself about the accuracy of your room.
Learn some @Invisible Alpha. Gypsum walls have a natural absorption that the absorbent is on. This gives significant low end absorption. See Bradley for documentation on this with gypsum board walls. And yes, I mix.
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Last edited by avare; 3 weeks ago at 08:30 PM..
Old 3 weeks ago | Show parent
  #14
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Quote:
Originally Posted by Mike Caffrey ➡️
Avre and I have similar opinions, though I'm more conservative in that my minimum is 12 inches of 5k GFR and his is 8 inches.

I don't know whether he does any mixing, but I do and I think that anything under the minimum is the same as nothing at all. One might argue it's worse because you've now got tangible evidence to support the lie you're telling yourself about the accuracy of your room.

It's so easy if you don't get hung up over a few inches of room space.

Ultimately, what's the point of doing it if you're not going to do it right?

That's what I don't get about OC 70X and slats and all of the layers of band aids people add to their cut corners.

And it's cheaper to do it the optimal way too.

I just posted a waterfall in a thread here of a 9x12x9 room and set up the short way that's +/-3 db down to 15hz. And most of the frequency spectrum is better than that.

But I prioritized results over 4-6 inches on each side of the room.

I'm sure you'll do what's right for you.
Well I'm not telling myself anything about the accuracy of my room. I don't know where that came from. IDK. I'm actually not going for the most accuracy in my room. I want rooms that sound good and are comfortable to listen to and perform in. In that regard I'm an exception here. I've never done a bunch of testing. As a matter of fact my 4" 2" gap OC 703 panels sound good to me. And it has made a hugely significant difference. When the panels aren't in the room t sounds TERRIBLE. Freaks me out. But as you said, all I did was place the OC 703 in the room to store and it was amazing.

Unfortunately I'm not a technical nerd kind of guy. Math is not what I have anything to do with. I appreciate the opinions of those who have done the math, knowing that it might not apply to me - different rooms and dimensions. Obviously I WANT accurate rooms. But I've been amazed at what a difference my little amateur attempts have made. And yes, I ant to doit right but this is taking SO FRIGGING LONG I'm losing patience.
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  #15
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Quote:
Originally Posted by avare ➡️
Learn some @Invisible Alpha. Gypsum walls have a natural absorption that the absorbent is on. This gives significant low end absorption. See Bradley for documentation on this with gypsum board walls. And yes, I mix.
Great. This is what we used originally. Going to have to replace it all now.

ALSO the mold abatement people are going to pull out all of the insulation. It got wet somehow. They'll test it. It could just be water, but where there's water there's most often mold. o here's a question for you. Should I replace the regular ceiling insulation with the Knauf R-38? Is that the pink and fluffy? Or the Safe n Sound? Or are those just for the acoustic panels and bass absorbers?
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  #16
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Quote:
Originally Posted by henryrobinett ➡️
Well I'm not telling myself anything about the accuracy of my room. I don't know where that came from. IDK. I'm actually not going for the most accuracy in my room. I want rooms that sound good and are comfortable to listen to and perform in. In that regard I'm an exception here. I've never done a bunch of testing. As a matter of fact my 4" 2" gap OC 703 panels sound good to me. And it has made a hugely significant difference. When the panels aren't in the room t sounds TERRIBLE. Freaks me out. But as you said, all I did was place the OC 703 in the room to store and it was amazing.

Unfortunately I'm not a technical nerd kind of guy. Math is not what I have anything to do with. I appreciate the opinions of those who have done the math, knowing that it might not apply to me - different rooms and dimensions. Obviously I WANT accurate rooms. But I've been amazed at what a difference my little amateur attempts have made. And yes, I ant to doit right but this is taking SO FRIGGING LONG I'm losing patience.
You missed my point. The part about people lying to themselves can't apply to you yet. It's when they've cut corners by being precious over a few inches of depth.

Your wording of what you're going for is wrong. You want the room accurate, you don't necessarily want your monitoring "flat" because that's not pleasant.

When music comes out of your speakers, it is what it is. Then it interacts with the room and creates nulls and peaks and there are no cases where that makes listening more pleasant. The interference from the walls is always destructive in either an additive or subtractive way.

That's why larger rooms are better in that the SBIR gets lower and lower because of the distance. If it's big enough, you just tame the reverberation (oversimplification).

The pleasantness comes from a "house curve" that's applied with EQ. Not corrective EQ like sonar works, though that has an optional house curve.

I haven't see a universal or even vaguely consistent standard for how people apply house curves.

There are a few people here who can give you excellent advice with using a device that goes between your converters and speakers and will allow you to apply either or both corrective EQ and a house curve.

I've settled on a mild one that I apply with a plugin and non-standard routing with my stereo bus. I use an aux rather than a master fader (allows post compression fades) and pre-fader sends for a peak limited aux so I can monitor that and print both versions, and also a "monitor controller aux" where I use a trim plugin with presets as a detented level control as well as using the sends to select speakers. Adding an EQ there means it's only in the monitoring path.


The more absorbent your walls and ceiling are, the closer it gets to being outside. You can not accidentally create an anechoic chamber with OC 70X or R-38 no matter how much you use. It's all somewhat reflective, even if the level is too low to interfere. Plus, the floor still exists.

You want accurate, monitors a room that doesn't alter what you hear and then you control the house curve, or you want monitors that aren't accurate and you like the "house curve" they impart. But there's never a time when you want your walls altering what you hear.

I started out with three 4" commercial panels in my room and was surprised at how little a difference they made. After some research and advice from the company who made them, I decided to try a bag of 8 batts of R-38. That's when I noticed a difference - like you're experiencing now. Just bringing them in the room.

There was a measurable difference too.

So I decided to add two more bags. Way better.

So I added more, and covered more area, then held some in various places by the ceiling and decided to cover the ceiling too. And not a cloud, the entire thing.

Each addition made it better and better and there was no way I could have grasped the differences the later additions would have made at the beginning.

When I was done, because I left them uncovered initially, it was like walking inside of Chewbacca because the Knauf R-38 is brown. It was comical but amazing.

It also absorbs light, so if you go this route, make sure you cover anything on the ceiling with white fabric so you get some reflection.

I specifically chose black for the back wall to avoid reflections in my computer monitor.


I moved all of this stuff to a different location at one point and then back. I found that stacking it and stretching a giant piece of fabric across a wall full could be done in 15 minutes and is, in a general sense, what Tom Hidley did at BOP studios.

It's a small room and I can't tell you what the dimensions are for a room to not be small, at least 20 by 20 and maybe more. For me the rule of thumb is, if it's in a home, it's small.

Search out some of Thrillfactor's posts. He says pretty much the same thing - the only way successfully treat a small room is to cover the entirety of every surface in deep, porous, fluffy absorption. I think everyone agrees that "deep" means as deep as you're willing to go, though Avre specifies 8" as a minimum and I think 12" is the minimum.


It took me a long time because I kept adding more.

I'd go buy 5-8 bags of Knauf R-38, stack it floor to ceiling and then make a wire grid drop ceiling and put the R-38 above that. Fluffy side facing in.

Then stretch fabric across it all and you're set.

Finding 8 foot wide fabric is a bit of a challenge, but it exists. You just have to figure out what you're going to attach it to. I like vertical self-tension rods for that.

There's a company called room dividers that sell some where you can attach a horizontal bar, and then use that to stretch the multi-strand wire for your ceiling grid.

A spandex based fabric, or actual spandex, will be acoustically transparent and you can stretch it to make a crisp looking wall/ceiling.

At this point, I could probably treat an entire room in half a day if everything was there and had a helping hand, and it wouldn't require more than an Allen wrench for the room dividers and some wire clippers and does no damage to walls or ceiling.
Old 3 weeks ago | Show parent
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Quote:
Originally Posted by avare ➡️
Learn some @Invisible Alpha. Gypsum walls have a natural absorption that the absorbent is on. This gives significant low end absorption. See Bradley for documentation on this with gypsum board walls. And yes, I mix.
The thoroughness of your posts has always given me the impression that you're primarily an acoustician.

I hope to hear the music you make/work on someday. I always enjoy your posts, so I'm curious what it's like.
Old 3 weeks ago
  #18
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Thank you Mike. I got that I missed your point. I’ll read through you and Avare’s posts again more thoroughly. You said unfaced knauf R-38?
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  #19
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Quote:
Originally Posted by Mike Caffrey ➡️

I'd go buy 5-8 bags of Knauf R-38, stack it floor to ceiling and then make a wire grid drop ceiling and put the R-38 above that. Fluffy side facing in.

Then stretch fabric across it all and you're set.

Finding 8 foot wide fabric is a bit of a challenge, but it exists. You just have to figure out what you're going to attach it to. I like vertical self-tension rods for that.

There's a company called room dividers that sell some where you can attach a horizontal bar, and then use that to stretch the multi-strand wire for your ceiling grid.

A spandex based fabric, or actual spandex, will be acoustically transparent and you can stretch it to make a crisp looking wall/ceiling.

At this point, I could probably treat an entire room in half a day if everything was there and had a helping hand, and it wouldn't require more than an Allen wrench for the room dividers and some wire clippers and does no damage to walls or ceiling.
So let me get this straight. I’m SUPER slow sometimes. Fast on guitar. Slow everywhere else! So you wouldn’t even make panels. Frame nothing. Just put knauf R-38 12” on all the walls and ceilings? Am I skim reading this right? LOL. Are you not putting an air gap between the walls and fiberglass? I mean this WOULD simplify things.
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  #20
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Quote:
Originally Posted by henryrobinett ➡️
Great. This is what we used originally. Going to have to replace it all now.

ALSO the mold abatement people are going to pull out all of the insulation. It got wet somehow. They'll test it. It could just be water, but where there's water there's most often mold. o here's a question for you. Should I replace the regular ceiling insulation with the Knauf R-38? Is that the pink and fluffy? Or the Safe n Sound? Or are those just for the acoustic panels and bass absorbers?
Knauf R-38 is acoustically the same thing as "pink and fluffy" but it's brown, not pink.

That seems like a good option, but for it to really be absorbent, you want the open face uncovered by anything other than an acoustically transparent material.

If it's practical and safe and up to code to leave that all exposed between the studs, you could have all of the work done for you.

You could stretch fabric across the studs and staple it in place and be in great shape. It's no problem to find fabric 8 feet tall and the width of 3-4 studs.

Maybe have them install some baseboards to hold the outlets and stop things from rolling under the fabric.

See what Avre says about this approach.


Check out Tom Hidley's use of fabric walls here:

https://www.soundonsound.com/music-b...-studios-story
Old 3 weeks ago
  #21
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Also, download REW and measure now.

Don't worry if you don't have a proper measurement mic. You just need to see the way the room changes.

Whatever the final decision, see if you can arrange to measure again after they have all of the insulation in, but before it's covered with whatever they're going to cover it with.

That will give you a really good insight into what having all of the walls covered in R-38 will do.

And if it's a garage, try a measurement with the door both closed and open. That will show you the effect of a truly acoustically transparent wall.
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  #22
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Quote:
Originally Posted by henryrobinett ➡️
Thank you Mike. I got that I missed your point. I’ll read through you and Avare’s posts again more thoroughly. You said unfaced knauf R-38?
In nearly all cases the back of this will go against something, like a wall or the box you've made for the panel.

The facing is a sheet of paper and that's going to be irrelevant if the insulation is installed paper side against the wall.

If I was hanging it free hanging infant of a wall with an air gap, unfaced might be helpful then, but for the most part it won't make a difference and faced will be a little easier to handle.
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  #23
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Quote:
Originally Posted by henryrobinett ➡️
So let me get this straight. I’m SUPER slow sometimes. Fast on guitar. Slow everywhere else! So you wouldn’t even make panels. Frame nothing. Just put knauf R-38 12” on all the walls and ceilings? Am I skim reading this right? LOL. Are you not putting an air gap between the walls and fiberglass? I mean this WOULD simplify things.
The short answer is yes.

I'd consider an air gap, but you were a little hesitant about 12 inches. If you add a 4" air gap, you're now at 16.

12" of R-38 without a gap is better than 8" with a gap.

I have two walls that are just R-38 stacked horizontally. At 12" deep and as light as it is, it pretty much stands on its own, even stacked 8' high. I then stretched 108" wide fabric the length of the wall and if the batts have tilted or fallen, that's enough to hold them in place.


I've also got a dozen 8'x2' panels I built.

They are "unframed" based on reading a note on the GIK site that pointed out a panel without solid sides gives substantially more surface area for absorption.

When they're lined up side by side, that's irrelevant, but that's how I chose to build them. After covering them with fabric, the front edges are far more crisp than I expected, but they're not crisp like a squared commercial panel is. I'd come up with some ideas for how to do that, but my goal was to keep everything super simple. I built all of these in a tiny Manhattan apartment.

The one thing I did for structure was order dozens of 24"x48" stretched canvases - the kind painters paint on.

before the pandemic, I found them for $10 plus shipping.

I used spray glue and glued the paper faced side of the R-38 to the canvases, which made them very easy to stand. When I decided to make them one solid piece, I used some aluminum strong ties to screw them together.

I'd considered hanging them on nails with multi-strand wire across the back like you hang a picture frame, but it occurred to me that the cheap lazy way of just tilting them backward so there was no chance of them falling forward, added an air gap at the floor corner and was in theory an acoustically superior approach.

Basically, for the first time ever, the less work I did the better the results.

Also, when I first started experimenting I measured the room without the canvases, and then with the canvases both in front and behind. I was told that in front they'd be too reflective in the high end, but that wasn't the case. There was some increase in the high end reflection, but I don't remember how much.

I sent it to the person who predicted that so they could see, and they said they considered the difference in the low end a remarkable improvement.

It seems there's some kind of membrane or limp mass effect of the canvas which is creaseless tight, but not drum tight.

These details are from quite a while ago, but I think the low end was effected the same way with the canvas behind the insulation.

I'd considered using two for each panel, because the canvas would provide crisp edges for the front.

My belief is that one canvas in the back is acoustically superior.

My current ceiling is a dozen or so canvases face down and then R-38 open face down on the back of them. I can hear that this is reflecting more high end than when I had raw R-38, but it's not an extreme amount.


But based on my understanding of your scenario, you've probably got a room that has the gypsum for walls and that's supported by studs with either 16 or 24 inch gaps and that when they rip all of that out and the damaged insulation, you could replace it with R-38 and then skip the gypsum and be in great shape.

If it was me, I'd go a step thicker than R-38 because of the extra depth you'd have where the old insulation was.

But this is where listening to me gets a little dangerous because I don't know anything about how the inside walls of a garage need to be in practical terms or legal terms.

There's also some sound transmission benefit from an extra rigid layer like the gypsum.

So acoustically, in terms of reflections of audio from the speakers, leaving it raw with R-38 with the paper side against the outer walls would be great.

Everything else, could be a problem. My guess is someone will point that out and may have some ideas for how you can address that - like putting the gypsum or drywall layer against the outer wall.

You could probably also have them replace everything with a very thin layer if insulation, cover it with gypsum that's still recessed between the studs and then add the R-38 using whatever parts of the studs are still exposed for structure. Then add an extension to a couple of the studs so they stick out as far as the R-38 and secure your fabric to that.


If you visualize the R-38 (Knauf) as a brown shag carpet, think swinging 70's Batchelor pad for the acoustic - meaning everywhere, and then stretched spandex over that to make it look modern.
Old 3 weeks ago
  #24
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This thread is so intriguing. My question is, well, partially for Henry - is this space primarily for mixing/monitoring, or are you going to be recording in there as well? And to Mike - is this very dry room suitable for recording acoustic guitar, horns, etc.? Of course anticipating the use of artificial reverb. My current room is very well covered with 4" thick rockwool . . . but I'm not perfectly happy with it. The R38 sounds like something I want to try. But I've never recorded in a room with that much absorption.
Old 3 weeks ago | Show parent
  #25
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4 Reviews written
🎧 20 years
Quote:
Originally Posted by Rob 28 ➡️
This thread is so intriguing. My question is, well, partially for Henry - is this space primarily for mixing/monitoring, or are you going to be recording in there as well? And to Mike - is this very dry room suitable for recording acoustic guitar, horns, etc.? Of course anticipating the use of artificial reverb. My current room is very well covered with 4" thick rockwool . . . but I'm not perfectly happy with it. The R38 sounds like something I want to try. But I've never recorded in a room with that much absorption.
How big is the space you are recording in? Dimensions?

Also how much of your space is covered in 4'' rockwool?
A tracking space as opposed to a control room is designed with a different intention. But the size does determine what is possible and how much flexibility you have in varying the treatment for a desired result.
Old 3 weeks ago | Show parent
  #26
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Quote:
Originally Posted by thethrillfactor ➡️
How big is the space you are recording in? Dimensions?

Also how much of your space is covered in 4'' rockwool?
A tracking space as opposed to a control room is designed with a different intention. But the size does determine what is possible and how much flexibility you have in varying the treatment for a desired result.
16' x 12' x 7.5'. About 70% of surface area is covered. I want to use this primarily as a tracking space. I have seen iso-rooms in some top studios using a mix of absorption and diffusion - cylindrical, slats, QRD.
Old 3 weeks ago | Show parent
  #27
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4 Reviews written
🎧 20 years
Quote:
Originally Posted by henryrobinett ➡️
So let me get this straight. I’m SUPER slow sometimes. Fast on guitar. Slow everywhere else! So you wouldn’t even make panels. Frame nothing. Just put knauf R-38 12” on all the walls and ceilings? Am I skim reading this right? LOL. Are you not putting an air gap between the walls and fiberglass? I mean this WOULD simplify things.
This is one of the reasons 8" is prescribed for broadband absorption as if you desire to frame it, buying a 1 x 10 x 8 ( really 9.25") is easily obtainable from your local Home Depot or lumber yard.

That also gives you enough depth for the 8" plus 1.25" for the fabric tracks if you want to make clean/professional installs of the fabric:
https://www.fabricmate.com/shop/fs15...egory=48#attr=

If you go to a 12" depth then you will have to have a special cut at your lumber yard which will raise the price substantially.
Old 3 weeks ago | Show parent
  #28
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🎧 15 years
Quote:
Originally Posted by Rob 28 ➡️
This thread is so intriguing. My question is, well, partially for Henry - is this space primarily for mixing/monitoring, or are you going to be recording in there as well? And to Mike - is this very dry room suitable for recording acoustic guitar, horns, etc.? Of course anticipating the use of artificial reverb. My current room is very well covered with 4" thick rockwool . . . but I'm not perfectly happy with it. The R38 sounds like something I want to try. But I've never recorded in a room with that much absorption.
This is a control room setting. I've recorded a high hat here, but that's it.

I bet an acoustic guitar or vocals would sound great in here.

It doesn't sound "dry" there's a floor and some furniture. But when you walk in to the next room, that room sounds loud and annoying.

One side perk I like is being able to talk on speakerphone without anyone having any idea.

I wish they all had a room that didn't have annoying slaps while they were on speaker.

I definitely want to try recording drums in a room like this. Nothing to cause frequency nulls or peaks. It should be a very pure sound of each drum,

It also would allow pulling the close mics back and still having a close sound.

There's also that drumbrella that people love for tightening the drum sound.

You can always open a door and put a room mic in another room, which I've done in a different space and was great for having a very contrasting sounding mic.
Old 3 weeks ago | Show parent
  #29
Lives for gear
 
🎧 15 years
Quote:
Originally Posted by Rob 28 ➡️
This thread is so intriguing. My question is, well, partially for Henry - is this space primarily for mixing/monitoring, or are you going to be recording in there as well? And to Mike - is this very dry room suitable for recording acoustic guitar, horns, etc.? Of course anticipating the use of artificial reverb. My current room is very well covered with 4" thick rockwool . . . but I'm not perfectly happy with it. The R38 sounds like something I want to try. But I've never recorded in a room with that much absorption.
Another option would be building some gobos where the performer side had the R-38 and you could minimize the room reflections in the close mic and then put some room mics on the opposite side for both the regular room sound and a little time delay.
Old 3 weeks ago | Show parent
  #30
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thethrillfactor's Avatar
 
4 Reviews written
🎧 20 years
Quote:
Originally Posted by Rob 28 ➡️
16' x 12' x 7.5'. About 70% of surface area is covered. I want to use this primarily as a tracking space. I have seen iso-rooms in some top studios using a mix of absorption and diffusion - cylindrical, slats, QRD.
The main issue in your space is the low ceiling.
The best tracking spaces i've ever recorded (even the one's that were your size besides the height) had ceilings above 10 ft.

With low ceilings you are limited in what you can do even with some diffusion, because the entire ceiling must be treated ( i always recommend go as deep as you can), especially in a tracking space where mics will be used. If you do the ceiling correctly it will actually make the space sound "airy" instead of closed in.

In a space your size a mixture of polys and slats properly placed can work, but I would stay away from QRD's personally.
One problem though is distant miking just won't be desirable option.
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