Design Studio in Basement

[afavreau]

Hi,

I'm looking for a plan for my studio that we are about to build in my basement.
I basically have 20"7" (628cm) X 12'5" (380cm) rectangle that I can configure as I wish. My ceiling is 8' (244cm) high.

Ideally, I would have a drum booth AND a Vocal/Ac Gt/Amp booth. But maybe I'm dreaming here so I'm ready to only have a drum booth.
Or maybe I should simply record everything in the main room? I'm open to that.

Anyway, I just want to optimize my space so I'm wondering what configuration should I go for? How many rooms? What shape?

Here attached, you will find a plan of our basement.

Thanks for your help

Andre Favreau

[thismanysounds]

Hi Andre,

In terms of keeping this tidy, I will answer in here. You are missing some important points from http://www.johnlsayers.com/phpBB2/viewt ... f=2&t=3231. The more information you provide, the better we can offer advice.

1-In a rectangle room is it always better to place the monitors facing the furthest wall or is ti ok the place them facing the closest wall?
Is a back wall of 12' and 5" far enough?

Generally, it is better to have them firing down the longest dimension. At that distance you will probably need to have a fully absorptive back wall.

2-What is the best shape for a control room? Is it with the side walls spreading further away from monitors?

This really depends on what you want to achieve. Angled walls are sometimes used to redirect first reflections away from the listening position. In a small room it may be a better idea to use absorption at first reflections. If the following don't mean anything to you yet, then I suggest you do some searching on the forum: Reflection Free Zone (RFZ), first reflection, room mode, standing wave, critical distance.

3-With the available space I have, is it better to forget the idea of having an isolation booth and just record everything in the control room?

If you only record yourself, or are happy to track with headphones my answer is 100% don't split up the room. You create more problems by having more smaller rooms.

4-How small can a control room be and still sound good? Or is it just that the bigger it is, the better it will sound?

There are fundamental reasons why larger rooms lend themselves to more accurate monitoring (see room modes). The ITU-R recommends 20-60m2 for stereo and 30-70m2 for multichannel.

5-How small can a drum booth be and still sound good? Or is it just that the bigger it is, the better it will sound?

Performance rooms are more taste specific. I know many producers who like the sound of a small booth. You will need a large room for it to have a smooth reverb. In a dry room, the smaller you go the more issue you have with room modes.

6-How small can a vocal booth be and still sound good? Or is it just that the bigger it is, the better it will sound?

See above. As vocals will not have the same low frequency, you can get away with them being smaller. That said, a big room will sound better and offer you more micing options.


You have not mentioned isolation at all. Isolation is how much your structure reduces the level of sounds going in and out of your room. There is little point in having a room with really accurate monitoring but no isolation from a busy road outside.


Colm

[afavreau]

Thanks. I appreciate the help.

We are planning to keep it as a single large room after all that we will isolate for sure.

I also have a small cold room (see attached file) that measures 1.32m X 1.73m X 2.44m(h)
This small room is surrounded by 3 external walls underground but is all made of cement.
Do you think this could become a vocal booth or something to place amps in with proper treatment/renovations?

I would normally record in the main room, but that would be just in case I need to record a second person at the same time.

Do you think it's worth it?

Thanks

Andre

[Soundman2020]

Do you think this could become a vocal booth or something to place amps in with proper treatment/renovations?

Probably fine for an amp, but it might be a bit small for vocals.

- Stuart -

[afavreau]

Because of sound or because singer will feel trapped once proper treatment is in place?

[afavreau]

Because of sound or because singer will feel trapped once proper treatment is in place?

Also, this is the wall I'm planning for my two inside walls for the 628cm X 380cm x 244cm rectangle room.

Is that ok? Anything I should improve? What do you think?

Thanks again

Andre Favreau

[afavreau]

Any help would be appreciated. I have to order material as soon as I can. Thanks

[rsmooth]

Andre,

Welcome to the forum and good luck on your build!

As far as the "my studio wall", I believe this will be making a triple leaf design, which is not correct. I also don't see any details on what you plan on doing with the ceiling. If you are in a basement, the ceiling is the most important part of isolation.

As far as ordering materials, I would hold off until your plan is ironed out. All the money spent on the materials will be wasted if not used correctly. Good isolation has a lot more to do with proper design than it does green glue or clips. If you provide ALL details associated with your build, you will get the build done right the first time.

Cheers,
Ralph

[afavreau]

Wow thanks Ralph!

You confirmed my suspiscion. So I read about triple leaf design and if I understand correctly, it would be better to remove the G-Proc in the middle of the existing wall, right?
(Here attached, you will find the new plan).

Thanks

Andre
[iYes this is for a basement, so I will write down my ceiling plan asap, I just need to confirm some things with my contractor before. [/i]

[rsmooth]

Much Better! I am personally not familiar with Sonopan's or Green Glue's effectiveness but I assume they are not cheap products. I am curious of the cost vs effectiveness. Maybe somebody else can chime in but usually an independently framed room with 2 layers of 5/8 gypsum (and batt insulation) is very effective. My basement control room is a true room-in-room with 2 layers of 5/8 gypsum and I can play music at 100db without disturbing anybody above me.

Ralph

[afavreau]

Sonopan seems to be an acoustic fibreboard mostly used in Canada. It sells at 19.95$Can per 4' X 8' panel. Doesn't something similar exist anywhere else?
⅝" Gyproc sells at 9.44$Can here.

Do you think the Fibreboard would help here? If so, is it at the right place?

Thanks

Andre

[afavreau]

Ok. So I just spoke with my acoustician and this is what he recommends - See studio Wall 4 (acoustician)

This is what I had according to my research though - See Studio Wall 3

Which is better?

[Soundman2020]

So I just spoke with my acoustician and this is what he recommends - See studio Wall 4 (acoustician)

I'm very surprised an acoustician would recommend that! That's a four-leaf wall!!!! Even worse, the air gap between the second and third leaf is very thin, which means the resonant frequency would be very high. sorry, but that wall would not isolate well at all fro low frequencies. This document might help explain the issues with 3-leaf and 4-leaf walls, and the reasons why they are perform very poorly for low frequencies:

https://app.box.com/shared/jcaoavdc8g

I'm also not sure what "Lepage Glue" is, but it is a bad idea to glue layers of a leaf together, as it prevents the individual layers acting as they are supposed to. The ONLY exception, is a product called "Green Glue", which is not really glue at all, despite the name. It is a special viscoelastic polymer that does not harden, and creates a thin constrained layer damping interlayer between the two sheets of drywall (gyproc). There are no substitutes that I'm aware of that have been proven to work and testes extensively in independent labs, like Green Glue has. If you cannot get real Green Glue in your country, then do not use anything else: just leave the layers with nothing in between.

This is what I had according to my research though - See Studio Wall 3
Which is better?

Yours is better. Much better! However, you do not need the resilient channel. The purpose of resilient channel is to decouple drywall from studs that have drywall on the other side. That is not your case, since you are building your wall correctly with a separate stud frame. The stud frame decouples the drywall much better than the resilient channel, and you do not need both. If the drywall is decoupled with one method, then you do not need to decouple it again with another method. So forget the resilient channel and the glue in your version, and you will have a pretty good wall.

However, the other leaf of the wall seems to have only 1/2" drywall on it, which really isn't enough. It would be better if you could add more mass to that wall by adding a layer of 5/8" drywall to "Out of studio" side of the existing drywall, or bu cutting strips of 5/8" drywall to fit between the studs on the wall cavity side of that drywall, holding it in place with cleats, and sealing around the edges with acoustic caulk. That would add enough mass to bring the resonant frequency down lower, which is good, and will increase isolation.

One other thing you could do: replace the layer of Sonopan Fiberboard with ordinary 5/8" plywood, OSB or MDF. IT is cheaper, more massive, and works just as well.


- Stuart -

[afavreau]

Wow! Stuart! Thank you! You don't know how much this is helping!
Ralph also opened my eyes on triple leaf walls at first. That's why I had doubts about my acoustician's plan.

So starting from the walls we prefer:

My Studio Wall 5.pdf

1-Out goes the resilient channel. I got your point.

2-But OSB would really be better than Sonopan? It's true OSB costs 8.67$Can here and Sonopan 19.95$Can per sheet, but Sonopan is very much used in Canada. I will probably go with what you say, but here is a study from the canadian government that you might find interesting. It's another part of the same study you pointed to me the other day, but it's in French. So I guess you can only look at the image on page 5 drawing #58. http://www.nrc-cnrc.gc.ca/ccmc/registry/pdf/12419_f.pdf

3-I don't know if I can put another layer of 5/8" Gyproc above the stairs, but I'll check with my contractor. I guess it could be done, but:
a) it will make the stairwell a little smaller,
b) at the end, the stairs will still be connected to the first ½" gyproc, thus absorbing some sound when people go up or down.
Maybe I should put some gyproc inside the 2X4" at this point as you suggested…

4-Also about insulation, I don't know if we only have these products in Canada, but I was thinking about Roxul AFB. Or should I go with Safe n' Sound which seems more like a residential product?
http://www.roxul.com/products/building+ ... /roxul+afb
http://www.roxul.com/products/residenti ... fe'n'sound

--And what thickness should I go for… 3 or 4 inches?

5-Lastly, about wood or steel studs, I made many comparisons from the report you sent, but it's still not clear. They are very close. My understanding is that in a simple wall, metal would be better, but in a double wall, wood may be slightly better. Does that make sense? Because steel studs are a little cheaper here.

Thanks for your help. I really appreciate it.

[Soundman2020]

2-But OSB would really be better than Sonopan? It's true OSB costs 8.67$Can here and Sonopan 19.95$Can per sheet, but Sonopan is very much used in Canada.

Lots of things are used in lots of places, but that doesn't necessarily mean they are used intelligently! For example, egg cartons are used in many places on the walls of "studios", but nobody who understands acoustics would suggest using egg cartons in a real studio!...

It works like this:

Sound is governed by the laws of physics. Sound is just variations in air pressure, so the laws of physics related to that explain how sound works, very well. According to those laws, there are only four basic ways you can stop sound getting from point "A" to point "B". Those are: 1) Make a barrier so massive (heavy) that the sound waves cannot make it move. 2) Make a barrier so rigid that sound waves cannot make it move. 3) Create a barrier that is so viscous that sound waves cannot get through (also called "damping"). 4) Remove all paths that the sound could follow from A to B, including air (in other words, create a perfect vacuum). That's it. There are no other ways of stopping sound. The last one here is impractical for a studio, since it would be pretty hard to build a wall that has nothing at all inside, not even air. The other three can be easily understood by a simple analogy: Stopping a bullet that is flying towards you. You can either put a massive barrier in front, so massive that the energy in the bullet's motion is insufficient to get through the barrier. Or put up a barrier so rigid (stiff) that the bullet cannot get through. OR put something very viscous in the way (a big block of jelly, for example) so that the energy dissipates entirely before the bullet gets through.

All of these are very analogous to how to stop sound. It turns out that each of these methods (mass, rigidity, damping) work better on some parts of the audio spectrum than on others (better at some frequencies, not so good at others). There are equations that describe exactly how sound is affected by each type, at each frequency.

For the frequencies that we are interested in stopping in home studios, it turns out that mass is the key. damping and rigidity are still important, but what really does the job for us, is mass. In fact, the equation that tells you all you need to know is called "mass law", and it goes like this:

TL(dB)= 20log(W) + 20log(f) -47.2

Where:
TL = "Transmission loss", or how much sound the barrier will stop, measured in Decibels.
W = the surface density (mass per unit area, in kg/m2) of the barrier,
f = the frequency (in Hz).

You can also write that another way, like this, which is easier to calculate:

TL = 20 log (F * M) - 47.2 dB


That's it. For a single leaf barrier, that equation tells you all about how to stop sound.

Notice there is only one item in that equation: Mass. There is no place where you can explain to the sound waves that this mass is better than any other mass because it is made from or "natural post-industrial wood shavings and wax" or "non-toxic contents without COV and Ure-formaldeide". You cannot fit that into the equation, because the single most important equation that tells you how well a barrier isolates has no place for that! It depend on one single factor alone: The mass of the panel, or more specifically, the surface density.

According to the brochure put out by the manufacturer, the density of Sonopan is 15 pcf, which is roughly 240 kg/m3. The density of OSB is typically around 580 to 650 kg/m3. That's more than twice as dense! So do the math, and see which panel will get you better isolation at any specific frequency...

OK, so I'm not being entirely fair, since the other two factors are still present: rigidity and damping should also be taken into account. On that front, OSB is far more rigid than Sonopan. For damping, yes, there is an advantage. Sonopan is self-damping to a larger degree than OSB, since it is wax based, not resin based. But the advantage is not that great.

Now, don't get me wrong: I'm not saying that this product doesn't work, or that the manufacturer lies. Not at all. I do not doubt that Sonopan works exactly as advertised, and will indeed provide the levels of isolation that the manufacturer claims, when used according to his instructions. However, I also have no doubt that a wall built identically but where the Sonopan is replaced by something else that has two or three times the mass, will perform much better. I know that, since that is what the laws of physics predict.

For example, one of the diagrams on their brochure shows that if you have a typical stud wall where one side is just a single panel of 1/2" drywall and the other is a panel of Sonopan plus a panel of 1/2" drywall, then get STC-43 rating. On the other hand, if you look at IR-769, you'll see that a wall made with one layer of 1/2" drywall on on one side and two layers of 1/2" drywall on the other side (in other words, where the sonopan has been removed and replaced by a layer of drywall), you get STC-51. (page 93, test number TL-93-039). Another diagram shows a wal with 2 layers of 5/8" drywall plus sonopan on one side, and one layer of 5/8" drywall plus sonopan on the other side, rated at STC 51. IR-761 says that the equivalent wall built with 3 layers of 5/8" drywall on one side and two layers of 5/8" drywall on the other side, will get you STC-54 (page 260, test TL-92-371).

Put it simply: sound waves cannot read price tags. They really don't care how much you pay for your mass. All they see is mass, and that is what stops them, regardless of how much you paid for it. So it makes sense to buy the materials that gives you the greatest mass for the lowest cost.... If you wanted to spend a lot of money to stop sound, you could indeed use panels made of titanium, just a few mm thick, and it would work very, very well. It would just cost you huge amount of money, though...

So that's the basic issue here. There are no magical materials that can somehow bypass the laws of physics. All materials must obey the same laws that govern the entire universe, and that's the situation here. You say that OSB costs half the price, yet is has twice the mass, so to me the decision is simple! For the same money, with OSB you get four times the benefit...

If you really do want to put something exotic in the wall that will help considerably, then use Green Glue between the layers of drywall. That has been shown to work, and it is most effective at low frequencies. However, it is not cheap. ...

Maybe I should put some gyproc inside the 2X4" at this point as you suggested…

That seems to be the best solution, yes. It's extra work, but very effective.

I was thinking about Roxul AFB. Or should I go with Safe n' Sound which seems more like a residential product?

Either one of those is fine. They are both good products.

--And what thickness should I go for… 3 or 4 inches?

As much as you can fit inside the wall! 4" on each side, would be perfect. You want as much insulation as you can get in there. The purpose of the insulation is to accomplish the third method that I mentioned: damping. The insulation damps the resonance inside the cavity, and also changes the way sound moves through the cavity, effectively making the path seem longer. So put lots in there, as long as you don't force it in so tight that it "bridges" across the gap, an connects the two sides again. The difference in isolation between a wall that has no insulation and a wall that is full of insulation, can be as much as 16 dB, but is more likely to be around 10 dB. That's a huge difference! It basically means that the wall sounds twice as effective, from a subjective point of view.

5-Lastly, about wood or steel studs, I made many comparisons from the report you sent, but it's still not clear. They are very close. My understanding is that in a simple wall, metal would be better, but in a double wall, wood may be slightly better. Does that make sense? Because steel studs are a little cheaper here.

To be honest, there isn't really much difference at all. We are talking about maybe 1 or 2 dB of difference at some frequencies. Hardly noticeable. So just go with whatever you feel more comfortable working with, and whatever makes the most sense economically.

- Stuart -