Design Studio in Basement

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

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/viewtopic.php?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

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

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 -

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

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

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

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]

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

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

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?

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

:shock: :?: 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 -

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: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.

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 -

Lol… best all time answer on a forum. This is awesome. Ok. So the wall is pretty much set now. I was then wondering in my case how much I need to treat the floor since I'm in my home basement. a) My goal is mainly for family and kids not to hinder the recordings. b) Also, I mostly, by far, record vocals and acoustic guitar, though I may record some drums later on. c) The wood floor I have right now is only 3cm high with carpet on top and does not connect to the the non finished side of the basement (see image above in yellow) which is still on cement. It was recommended to me to just put a Thermoplastic Membrane on the floor. Product M33-111/R on this page: http://www.royalmat.com/product-list.aspx What do you think? Should I treat the floor? How important should it be for me? Thank-you so much again!

Andre, Looks like you have your wall figured out! I'm so glad you didn't rush it because you now have the proper design. I would say that the floor is not an issue for concern. Concrete is very good at isolating. I would say to simply follow the manufacturers instructions for installing over concrete. The biggest is still your ceiling. What are your plans with that? Ralph

Hi Ralph, Yes you are right, the ceiling will be the most important part. For this, I would like to create something like the wall, but at this point, I'm not exactly sure what is above the actual Gyproc ceiling. But speaking with my contractor yesterday, this is what I understood: 1-Remove the existing Gyproc ceiling 2-Make sure the studs of the walls are disconnected with upstairs 3-Put all the Roxul Safe n' Sound we can up there between the studs in the midst the wires 4- Space 5-Build a new stud structure resting on the new walls on the side with Roxul again 6-MDF 7-Gyproc ⅝" test the noise level, then if needed, add: 8-Green Glue 9-Gyproc ⅝" For the floor, I'm not sure why my former acoustician was telling me I needed to do something about it. I know there's no decoupling "U"s and no isolation under, but I mean I'm just not what sound that can come from there. I guess he was saying this in regards to the acoustics inside? Maybe if a drummer plays? Or a bass amp?

1-Remove the existing Gyproc ceiling 2-Make sure the studs of the walls are disconnected with upstairs 3-Put all the Roxul Safe n' Sound we can up there between the studs in the midst the wires 4- Space 5-Build a new stud structure resting on the new walls on the side with Roxul again 6-MDF 7-Gyproc ⅝" test the noise level, then if needed, add: 8-Green Glue 9-Gyproc ⅝"

Perfect! That is, indeed, the way to do it.

I guess he was saying this in regards to the acoustics inside? Maybe if a drummer plays? Or a bass amp?

Plain concrete is an amazingly good floor, acoustically. It is reflective, hard, solid, and rigid. Just what you need, provided that the rest of the room is treated well. If the concrete is in poor condition (cracked, stained, pitted, etc.) then a very good alternative is laminate flooring. Or ceramic flooring. So you do not need anything else on your floor, and if you did try, you would end up losing headroom above you, as well as reducing the room volume, both of which are bad. - Stuart -

Stuart, Just to make sure I explained myself correctly I do have a plain concrete floor underneath, but on top of it, I have a very low (3cm) wood structure with carpet on top. I'm saying this because your answer seems to imply that the studio floor on top concrete. Also, I'm not sure if that's what you're saying, but I've never heard that reflective floors are good for treating a room. Aren't all acoustic products made out there designed to absorb? Personally, I would prefer laminated floors eventually instead of carpet. Thanks again for your help

I do have a plain concrete floor underneath, but on top of it, I have a very low (3cm) wood structure with carpet on top.

:shock: Ooops! The you basically have a resonant cavity for your floor! That's not good at all. The wood structure should go, so you have only the concrete for the floor, and then put your laminate on top of that, if you want to.

Also, I'm not sure if that's what you're saying, but I've never heard that reflective floors are good for treating a room.

Take a look at photos of professional studios around the world: How many of them do you see with carpet on the floor? :) The answer is pretty close to "zero". How many of them do you see with hardwood floors, or ceramic floors, or concrete floors, or other types of solid, hard, reflective floor? The answer is pretty close to "all of them". There's a reason for that, based mostly on the pschyo-acosutics of how our brains perceive the rooms that we are in, acoustically. If the floor is "hard" (acoustically), then our brains have an easy time of figuring out the room. If the floor is soft, then that's a different story: there is no reference surface that our brain can use to figure out where our feet are, so it also cannot figure out where our head is. That's one reason why being in an anechoic chamber is very disorienting and unpleasant: your brain can't figure out where you are, since there are no reflections from the floor that it can use to figure out which way is which. The same applies to mics: they pick up the room acoustics, and that gets to be part of the recording. If you place a mic very close to a hard reflective surface, and then listen to the recording of that in a normal room or on headphones, it sounds "wrong". If you place a mic at head height in a room with a hard floor, the recording sounds "right". If you then put carpet on the floor, it sounds "wrong" again. If you put overhead mics on a drum kit, and they are close to a reflective ceiling, the whole drum recording sounds "wrong". If you make the ceiling very absorptive, the recording sounds "right" again. Our ears and brains are rather sensitive to the acoustic clues about the room that are contained in recordings, which is why designers work so hard to get live rooms sounding good and control rooms sounding neutral. Using the floor as a consistent reference surface makes it a lot easier.

Aren't all acoustic products made out there designed to absorb?

Not really: Most diffusers are designed to NOT absorb, but rather to scatter sound, by reflecting it in different directions and with different timing and/or phase. Some devices (such as slot walls) reflect some frequencies and absorb others. In an RFZ room, most of the front of the room is entirely reflective, with little or no absorption, since it is designed to reflect everything away from the mix position. Some devices reflect, diffract, diffuse and absorb all at once, in different parts of the spectrum. Gobos ar designed to reflect on one side and absorb on the other. Space couplers are design to transmit sound efficiently from one acoustic space to another, while reflecting, absorbing, diffusing and diffracting as little as possible. Etc. There are many ways of treating sound, and not all of them involve absorption. For a small room, yes, probably most of the treatment will be absorption, but that's just one method of acoustic treatment.

your answer seems to imply that the studio floor on top concrete.

Right. that's the way it should be. Or if not concrete, then some other type of hard, solid, reflective surface.

Personally, I would prefer laminated floors eventually instead of carpet.

:thu: Yup! In fact, that's the only sensible way to go, if you don't like concrete. But even then the laminate flooring must be installed on a massive, hard, rigid surface, with no air cavities below.... The only place you see carpet in most studios is on drum risers (where it does serve an acoustic purpose and also a practical purpose), sofa risers (where it is mostly decorative, not acoustic), and perhaps to cover some types of acoustic treatment, but in that case it is proper acoustic carpet, which is transparent to sound and has no effect on it. The acoustic properties of typical commercial carpet is terrible for control rooms and studios in general. In fact, it is the exact opposite of what you need in a small room:: Carpet absorbs high frequencies very well, mids to some extent, and lows not at all. What you need is the other way around: Absorb lots of lows, a fair amount of mids, and no highs... - Stuart -

Thanks Stuart! I'm learning and it makes sense. I still have a few questions though. 1) What is all the teaching about floating the floors with U-boats and 2"X4", and then putting mineral fibre? http://www.auralex.com/sound_isolation_ ... _uboat.asp Is it not to decouple the floor from other rooms also? Can concrete floors also transmit sound from one room to another? 2) Just to make sure, you do realize that my one room studio is for recording AND mixing, right? 3) In Canada our basement cement slabs are cold and rough. This is why they are not so appreciated and considered unfinished. Ceramic is also mostly used upstairs and only sometimes downstairs because they are cold. That's why I'm more interested in a laminated floor. However, my cement floor also has a slight slope going towards the middle of the house in case of water damage. So I checked with my contractor, and he tells me that it would be possible to level the cement. So that's probably what I should do, right? Is that the cost effective approach? Thanks for your much appreciated help

Andre Looks like you have most of the details worked out ! Nice work. I am not sure exactly when or how but "floating" a floor with those u-boats is probably the biggest misconception in building a studio. A floating floor is not necessary in your application, especially being on concrete. Even if floating a floor was called for, those u-boats should not be used. I am sure Stuart will give you all the science behind why. Also, I am pretty sure everything Stuart has suggested is correct for your recording/mixing room. As he already stated, reflective surfaces are used almost exclusively for flooring. My friend used to work at a very well known studio in nyc that had carpet under the console and there was always problems with static electricity! Acoustically speaking though, hard surface is best. My basement studio is also cold and rough. Depending on the pitch of the slope, leveling may or may not be necessary. I personally used a self leveling skim coat on my floor and then installed laminate on top.

1) What is all the teaching about floating the floors with U-boats and 2"X4", and then putting mineral fibre? http://www.auralex.com/sound_isolation_ ... _uboat.asp Is it not to decouple the floor from other rooms also?

Wellllll.... ummmm .... I don't want to be seen as dissing the products of a company, but once you understand what it REALLY takes to float a floor correctly, then you can judge for yourself how well those work. Please take a few minutes to read over this thread: viewtopic.php?f=2&t=8173 That explains it very well. And if you want further conformation NOT from this forum, then here's a link to another forum that discusses the same thing: http://prorecordingworkshop.lefora.com/ ... n-mistakes If you really want to understand the technical details of what it takes to float a floor properly, then here's a really good paper on the subject, that comes from a very good country... ( :) ) : http://archive.nrc-cnrc.gc.ca/obj/irc/d ... /ir802.pdf If you look at the graphs and read the test carefully, you'll see several examples of how floors that are not floated correctly not only don't work, but in fact they can make matters much worse than doing nothing at all! In some cases, badly done floors lost 10 dB (or more) of isolation, and exactly in the part of the spectrum that matters most: the low end. Here's a couple of other interesting threads from the forum that mention the same issue: viewtopic.php?f=2&t=8134 viewtopic.php?t=8135 Basically, in order to float a floor correctly, you need LOTS of mass. Much more than you can get from a few sheets of plywood on a stud frame. The only practical way of getting that amount of mass, is by floating a new concrete slab over the existing slab, using this type of device to jack up and decouple the new slab after it is poured: Or these: Here's an example of a such a floor floated correctly: And a view underneath, showing the springs and steel beams that it is floated on: Interestingly enough, there's a paper on the Kinetics web site that analyzes this problem in detail, and comes to the conclusion (from the graphs they show) that you need a floor that weighs about 300 kg/m2 over an air cavity of at least 10cm in order to get the resonant frequency down low enough that you are isolating the entire spectrum... As a point of reference, a sheet of 19mm plywood weighs about 10 kg/m2, so you'd need to pile on about thirty layers of plywood to get that much mass... :shock: :!: (that would only be about 57 cm thick....). Or you could pour a concrete slab about 1.3 cm thick. (Theoretical thickness for the right amount of mass: in real life it would have to be a bit thicker, for strength and stability).

Can concrete floors also transmit sound from one room to another?

Yes they can, but usually only impact noise, which basically means something hitting the concrete directly, or making it vibrate by direct contact. Have you ever stayed at a hotel where the guy in the room above dropped one shoe, or fell out of bed? That's impact noise, and concrete does transmit it. Which is why it's a good idea to have laminate flooring, since you install it over a pad of spongy underlay, that provides both thermal insulation (a bit) and acoustic decoupling. Most studios also put drums kits on a small isolated platform called a "drum riser" for the same reason, and set bass cabinets and guitar amps on top of isolation pads. Concrete does not normally transmit airborne sound, since it is so massive that you need a lot of energy to make it move. There just isn't enough energy in typical sounds to accomplish that: you'd really have to turn up the volume to extremey high levels to do that. Also, there's the issue of "damping": since your concrete is poured directly in the ground, the entire planet is damping it, so it really does not want to move, and even of it does move, the damping effect stops it really fast. That's why we don't recommend building a studio on floors that are NOT on the ground: even concrete floors on the second or third floor of a building aren't so good at isolating, because they don't have the ground under them to damp.

2) Just to make sure, you do realize that my one room studio is for recording AND mixing, right?

Yup! Not a problem.

3) In Canada our basement cement slabs are cold and rough.

Yup! I go to Canada every couple of years, either for business or to visit family in Ottawa, so I'm aware of how cold it gets. There are special underlays for laminate flooring meant for that, to provide a thermal buffer. Normal underlay is reasonable, but the thicker stuff is better, both thermally and acoustically. There's one type that has metal foil on one side, for that purpose.

However, my cement floor also has a slight slope going towards the middle of the house in case of water damage. So I checked with my contractor, and he tells me that it would be possible to level the cement. So that's probably what I should do, right? Is that the cost effective approach?

That's what I would do, if that were my place. :) If the slope is not very big, then you might be able to live with it, but I would spend the bit extra to get some leveling cement in there, and get it nicely smooth, flat and level. Laminate flooring must have a smooth, flat surface underneath: you cannot lay it on a surface that has bumps, dips, or is uneven. Check the manufacturer's instructions to find out what the maximum unevenness can be. - Stuart -

OKAY!!! Wow!! Now I feel like I have a plan! The direction of the whole thing is pretty clear now for the floor, the ceiling and the two new walls (the other two are against the outside of the house, so I'm planning to leave them as is). 1) Since the new walls will be built up from the cement floor, do you think that pads underneath are still necessary? Or should I use them above the wall to separate from the new ceiling resting on that wall? http://www.acoustiguard.com/Iso-Sill-Plate-Isolation/ 2) As for acoustic sealant, do you think I need something special or any kind from my local store is fine? Here are a few I know. http://www.lepageproducts.com/ProductDetail.aspx?pid=92 http://www.acoustiguard.com/Green-Glue- ... g-Sealant/ http://www.lepageproducts.com/ProductDetail.aspx?pid=78 3) For my floors, I also thought of Floating Vinyl. What do you prefer between this and a Laminate floor ? Would any type of underlay be a good thing? 4) I also have two water pipes following the upper corner of the two walls that are against the outside of the house. I'm not too worried about them because I only hear them when the washing machine and kitchen sink upstairs are functioning, so I can easily control that. I would still prefer to isolate them anyway. How should I approach that. This is what I found: http://www.acoustiguard.com/fire-rated- ... materials/ http://www.acoustiguard.com/Barrier-mat ... ded-vinyl/ 5) As for electricity, I want each duplex to have its own connection to the Electric box. From Jim Pavett's videos on Macprovideo.com, he seems to be saying that we should only use individual cables for positive, neutral and ground. He also seems to be saying that each outlet of the duplex should also have its own ground all going through their own metal conduit. But I'm not sure how to do that. All cables I see in stores have at least two wires. So is there something I'm missing? This is what he says: All outlets have an isolated ground wire, making a full home run back to the circuit box. This means not only the duplex outlet, but each individual outlet of the duplex. In other words, two separate sets of wires running back to the circuit box. That's a lot of wires. Some Hi-Fi guys also tell me I should use gauge 10 cables plugged into 20 amp breakers in the box. How should I organize all this? Thanks once again!