Input on my studio design please

Hi All I am turning my garage in to a studio/ office in Los Angeles and would value input on my designs. First up, I have spent the best part of 2 complete days scouring this forum and other sites to get to where I am at now. I have also met with 3 electricians and my contractor several times on site to look at my specific requirements. Everything is being done by licensed tradesmen to code. I currently have a studio that research was done for so I'm someway along the road here BUT happy to learn more as I want my new space to "ROCK ASS"!!!! OVERVIEW. I have a total budget of about $8000. The goal is to build a simple and as sound proof as possible studio and day office. I tend to do mostly electronic production with vocals and occasional live instruments such as cello, guitars, hihats and sampling. Therefore the main space will be dedicated to a control room/ workshop area with a small "booth" for the live stuff. Like many people i run a MAC based set-up with plug-ins so I don't have a huge amount of gear. I custom built a desk with built in Speaker mounts 3 years ago that has been great and this will stay at the heart of my rig. My gear list is as follows .... KRK 15" sub Alesis M1 Mk2 monitors (don't laugh as they actually are great when mounted and used well!) Mac Pro with 24g ram etc Yamaha electric piano M-Audio Ozonic Appogee Dual Analog factory synth behringer headphone amp various mics, etc I already have a decent amount of acoustic treatment that I will take with me to my new studio. This includes : 3 x ATS acoustics 24x48x4" panels (used on the wall in front of me when mixing) 6 x Auralex LENRD bass traps which I plan on replacing 8 x 24x48x2" foam panels The garage is 18'x17' (internal measurements) with a pitched roof. The walls are 8' tall and the pitch extends to approx.15" in the center. There is one side door that is 3 ft wide and 7 ft tall. PLAN. Electrical: we are running 2 new circuits to the garage. one for the A/C unit (which will be a Soleus air mini split unit mounted on the back wall behind the mix area) and overhead light which will be on a dimmer. The other circuit is for the studio gear which will be on 5 x dual outlets with surge protection. Outer walls. The garage is OLD, there is a new 25 yr roof being put on now that will be a layer of plywood over the existing frame. It will look new and be dry (i hope) but I am aware provide minimal sounds proof benefits so...... the roof will be lined with R13 insulation as will all existing side walls. This will be a 4" insulated buffer to the wooden exterior frame and stucco. The garage door is being bolted shut and then sealed around all edges and then R13 is again being applied to the inside of this door. The ceiling will maintain its pitch (which I am thinking is good for acoustics and also "creative space"). it will be finished with 2 layers of drywall with green glue. So there will be no air gap here. not sure how else to create more sound proofing here. We are also considering installing 2 x 2'x3' fixed closed skylights to allow some natural light BUT am concerned about sounds leak from these - advice please!!! Main room : there will be an air gap all the way around this room of 2 inches. Do I need more? Then we will have the walls built in 2x4" framing and lagged with R13 open back to the air space. This will then be finished with 1 -2 layers of drywall (+ green glue if second layer applied) depending on budget. The outer garage side door will be an outswinging glass panel door with extra rubber sealing. Then there will be a solid internal and inner swinging door to the main room which will only have an handle to pull it open and be on heavy duty hinges so that it can be covered with extra layers and a double seal to prevent sound loss. The idea is that when I am not doing music work that both of these doors will be open to allow light and air in so i can see the garden. The glass door can be closed but still allow light in if its noisy outside. The "live" booth will have the "open backed" walls covered with fabric on 2 sides and drywall on the other 2. It will measure approx. 5' x 4.5' with the same solid door as on the main room. There will be a patch bay to the main room. Main room walls will angle out giving a 6-10 degree splay on 3 walls with a right angle in the office area corner. Superchunk bass traps will be built in 3 corners from floor to ceiling and 24-30" wide. These will be rock wool filled then covered in fabric on the studio side. The bass trapping in the office corner will likely be 4' tall from mid wall to ceiling height to allow for office furniture. There are 3 beams internally which I might consider hanging clouds from IF budget allows and if the acoustics need it. A cloth sofa will be at the rear of the mix area to hopefully absorb a bit more sound. I am planning on later building a custom diffusor/ absorption panel for the rear wall. The floor will be carpeted over the existing concrete. The space between the base of the drywall and concrete floor will also be sealed PHEW .... ok, attached is a basic aerial plan - the black external line is the existing garage and the RED thick lines are NEW interior walls. I've also attached my aerial wall construction picture idea. THANKS everyone :)

OK, I just followed the link across from your other thread that deals with the same studio! Please try to keep everything in one thread, to avoid confusion.

I custom built a desk with built in Speaker mounts

It would be good to see a photo of that, but in general it is not good to have the speakers on, in, or otherwise attached to the desk, for many reasons. So that would be the first thing I would consider: move the speakers onto massively heavy stands located behind the desk, and up against the front wall.

8 x 24x48x2" foam panels

When you say "foam", what type of foam? If it came from a reputable manufacturer of acoustic products then you are probably OK. Otherwise, you are probably NOT OK. There are many different types of foam, and only a few of them have any use, acoustically. There are several unscrupulous "foam by mail" places around, that sell things like packing foam and upholstery as cheap acoustic foam, when of course it is useless. Proper acoustic foam is not cheap. So it would be good to check on that, and make sure that your foam really is acoustic foam.

The garage is 18'x17'. The walls are 8' tall and the pitch extends to approx.15" in the center.

Not ideal dimensions: The 18 and 17 are too close for comfort. But that can be fixed with the inner-leaf design.

Electrical: we are running 2 new circuits to the garage. one for the A/C unit (which will be a Soleus air mini split unit mounted on the back wall behind the mix area) and overhead light which will be on a dimmer. The other circuit is for the studio gear which will be on 5 x dual outlets with surge protection.

Star ground. Very important. Don't forget to make sure that the entire studio is wired with star grounding.

there is a new 25 yr roof being put on now that will be a layer of plywood over the existing frame.

Excellent! You are in a great position to get good isolation! Make sure they use 3/4 in plywood for that deck, and that they seal the joints between the plywood (flexible caulk). It's a little extra work, and a little extra money, for a lot extra benefit in isolation.

The garage door is being bolted shut and then sealed around all edges and then R13 is again being applied to the inside of this door.

That will be a weak point. Garage doors do not have much mass, and do not provide much isolation. Also, if that is a typical thin metal door, then it will resonate /vibrate) at undesirable frequencies. If you need isolation, then I'd strongly suggest building a simple stud frame wall in front of that, with 5/8 drywall on one side of the frame.

The ceiling will maintain its pitch (which I am thinking is good for acoustics and also "creative space"). it will be finished with 2 layers of drywall with green glue. So there will be no air gap here

Yes there will! There will be an air gap of at least 3-1/2" (assuming the trusses are 2x4), and probably much larger, if the trusses are 2x6, 2x8, etc. so you WILL have an air gap up there. And you MUST have an air gap in a roof: I'm betting that your local building code actually requires eave vents and a ridge vent (or gable vents), to correctly ventilate the underside of the roof deck. Better check that, and change your design accordingly.

not sure how else to create more sound proofing here.

Use Resilient Channel to mount the drywall! That decouples and creates a proper MSM system up there. But do make sure that it really is Resilient Channel, not a cheap substitute, or even worse, plain old hat channel. If all you can get is hat channel, then use RSIC clips to isolate that.

We are also considering installing 2 x 2'x3' fixed closed skylights to allow some natural light BUT am concerned about sounds leak from these - advice please!!!

It IS possible, but you do need to retain the same surface density in the skylight panels as for the rest of the roof, and also the rest of the ceiling. That pretty much implies glass for both panels, since plexiglass is not dense enough. So it can be done, but there is the issue of cost... Thick laminate glass is not cheap.

Main room : there will be an air gap all the way around this room of 2 inches. Do I need more? Then we will have the walls built in 2x4" framing and lagged with R13 open back to the air space. This will then be finished with 1 -2 layers of drywall

Sounds to me like you have at least a 3-1/2" air gap there too, and probably more like 8". If you are using 2x4 framing, it is impossible to get a 2 inch air gap (unless you build both leaves inside-out, but you don't seem to be doing that, from the description of how the wall will be built).

The outer garage side door will be an outswinging glass panel door with extra rubber sealing.

Once again, that will be expensive: A door fitted with thick laminate glass is not going to be cheap, unless you meant that it will just have a small glass window in it?

The idea is that when I am not doing music work that both of these doors will be open to allow light and air in so i can see the garden.

That will work for natural light, but not for air. If you were planning to ventilate the room like that, it will not work, and probably will not pas code either. Air has to have a reason to move: a pressure differential. Your room will have double absolutely air.tight hermit seals all around it, so just opening the single door does not create a pressure differential: the air inside will just sit there, without moving, and so will the air outside. Nothing will happen. Air will neither enter nor exit. That's not a good plan for ventilation. You absolutely do need a proper HVAC system, no doubt at all. This seems to be the single area that is most often overlooked or greatly underestimated in home studio designs. You MUST have a method for ventilating/heating/cooling/dehumidifying the room properly. Think of it this way: You will be building not just one but two absolutely perfect air-tight seals around that entire room. There is no way for air to get in or out. You will also by installing very large quantities of insulation for acoustic reasons, but the insulation you will use also has excellent thermal properties. So you will basically be wrapping your room in very, very thick blanket, plus two very thick plastic bags. One question: How long can you hold your breath? :) Another question? Do you like hot stale air? :) You will be working inside a plastic bag inside a blanket inside another plastic bag. How long do you think the air will remain breathable and pleasant in there? Add in some electrical equipment, instruments, a couple of other people, and it will get hot and stuffy real fast. The volume of your final room will be around 2500 cubic feet. ASHRAE has some rather complex formulas and tables for calculating how much air you need to move through that room in order to keep you alive (and legal), but a good basic rule of thumb is about 900 cubic feet per hour (15 cfm) of FRESH air coming in from the outside, and therefore 900 cubic feet per hour of stale air going out. That's minimum, for one person. You live in Santa Monica, California, which is both warm and humid, so your needs are higher. Add another person to the room, and you double that. Allowing for about four or five people in there, you need to replace the entire air volume inside that room several times per hour. You CANNOT do that by opening the door! Not even by setting up fans in the doorway. In reality, you should probably be moving air around at about 150 cubic feet per minute, and about one third of that should be fresh air coming in / stale air going out. The rest is just recirculating, and being cooled / dehumidified by your air conditioner. You already show that, and it seems to be in a good location. Just in case others are reading this, I'll add an explanation of why you did that, and why it is so important: Apart from using up oxygen and pumping out carbon dioxide (plus other gasses), your body also puts out heat and humidity. Your equipment also puts out heat. So do your lights. So do your amps. That heat has to be removed from the air, since it certainly ain't going out through those triple-insulated walls! The humidity also has to be removed, since it too is not going to leave of its own accord: it has no way of getting out! Add to that the fact that high humidity is not good for your equipment and instruments, and that rapid changes in humidity (such as from opening / closing the door every few minutes) will cause changes in the sound of your instruments, and even the sound of some mics (many condensers, for example, are sensitive to humidity), and you have a recipe not just for an unpleasant atmosphere, but also for lousy sound. So you absolutely do need something like the mini-split system shown here. But I'd strongly suggest that you re-think your ventilation system to keep your room usable. It doesn't need to be complex: just a pair of suitable sized fans with a couple of properly dimensioned silencer boxes will do the job. But it DOES need to be there, and it does need to be designed correctly. I very much doubt that you'll pass inspection without ventilation.

The "live" booth will have the "open backed" walls covered with fabric on 2 sides and drywall on the other 2

What do you mean by "open backed" walls? Are you talking about inside-out construction? That's what it seems like, from the comment on the diagram. (If not, then maybe you could sketch out a diagram of what you are planning there.) If that is the case, then you will not have much isolation at all in that "iso" booth. I'd guess at maybe 20 dB, max. That's about half of the isolation that you get from a typical house wall. Is that what you are hoping for?

Main room walls will angle out giving a 6-10 degree splay on 3 walls

Why on 3 walls? You are wasting a lot of space by splaying the rear section of the right side wall, plus you are introducing potential problems with reflections off that angled rear wall. The general rule of thumb is that rooms should get wider towards the back (walls splayed outwards), not narrower (walls splayed inwards).

There are 3 beams internally which I might consider hanging clouds from IF budget allows and if the acoustics need it.

Acoustics will need it. Not much doubt about that. The ceiling is a potential major issue for first reflections, plus that is a small room, so it will need lots of absorption, mostly for bass. So a very large cloud up there is certainly something you will need.

I am planning on later building a custom diffusor/ absorption panel for the rear wall.

The room doesn't seem big enough to be able to benefit from most types of diffuser: what did you have in mind? Also, you seem to be aiming for a partial RFZ design, so the rear wall should be highly absorbent. It would be easier / cheaper / more effective to just cover most of that rear wall with absorption, spaced away several inches.

The floor will be carpeted over the existing concrete.

Ouch! Why cover a perfectly good concrete floor with carpet? If there is one thing that is pretty much guaranteed to wreck your room acoustics, it is carpeting the floor. How many high-end professional studio control rooms do you see where the floor is totally covered in carpet? There's a reason for that.... :) it is a lousy acoustic device! Carpet does the exact opposite of what small rooms need. I like to call it "random destructive absorption". Carpet absorbs high frequencies quite well, mids somewhat, and lows not at all. On the other hand, what small rooms need is major low frequency absorption, a bit on the mids, and practically nothing extra in the highs. Carpet will make your room sound, boomy, muddy, dull and unpleasant. Forget the carpet and just leave the floor as plain old bare concrete (which is a great floor, acoustically), or if you don't like the looks of concrete, then lay another type of hard floor, such as laminate flooring, or hardwood, or even some types of linoleum look good these days.

The space between the base of the drywall and concrete floor will also be sealed

That's good, but you also need to seal all of the OTHER gaps around the room. The entire existing outer leaf must be sealed absolutely airtight: you have to inspect every single nook and cranny, and tanker loads of acoustic sealant in to everything that even looks like it might be a gap. Even if you are certain that it is not a gap, then seal it anyway, just in case. And then repeat the same procedure for the inner leaf, once it is complete. You need two hermetic seals around you.

attached is a basic aerial plan -

I would suggest several things (some of this is repetition of what I already said): First, get the speakers off the desk and onto massive stands. Set them up with the speakers tight up against the front wall, 28" from the side walls (implying 76" between them) with the acoustic axes of the speaker at a height of 1.2m (about 47") above the floor, and the speakers angled inwards at about 30° (NOT at the 45° angle shown). Next set up your chair about 68" from the front wall. Or rather, so that your ears are 68" from the front wall. If you did everything correctly, the speakers are not aimed perfectly at your ears. The center of the speaker cones should be about 12" from the front wall (due to the depth / angle of the cabinet, plus the 4" of acoustic insulation), which means that if you imagine that the acoustic axis is a line extending out the front of each speaker cabinet, those two lines will meet at a point about 14" behind your ears. That leaves you with your speaker and listening position geometry set up perfectly. ON final thing you need to do: adjust the bass roll-off of the speakers, so to correct the power balance back to normal. Next, straighten out that right side wall, so that it runs parallel the outer leaf wall. Finally, add another wall on the left, mirror imaging the one on the right, in order to get good symmetry for the room. That does mean that your office is in a separate room. Not a big problem. Those would be my suggestions, FWIW. - Stuart -

awesome input stuart - thanks!!! attached is picture of my current desk mounted speakers/ monitors - the KRK sub is under the desk at the back. The speaker stands have a rubber pad between the base mount and desk then the same between the wooden panel and top of the stand arm. On top of the wooden panel are Auralex MOPAD's. I kinda want to keep this BUT you are swaying me and I do have 2 spiked quiklok speaker stands that I could use. Strangely, my current set-up sounds great and mixes translate really well to other systems, yet the walls are parallel, I have minimal bass trapping but I do have a curved wooden roof that starts from 11ft and hits 15ft at its peak, plus a large curtained storage area at the rear of the room full of suitcases, duvets and pillows ::))) i will certainly look over your other points and post more here asap... My "acoustic panels are auralex sonolite panels mounted on thin plywood which is then attached to the wall by screws with a rubber ring between the wood and drywall. I need to read up on "Star Grounding" as I have no idea about this! I hear you on the garage door - my original plan was to build that stud wall frame, fill with R13 and then drywall but I was worried about the whole "mass/air/mass/air/mass" being bad thing so scrapped it - but now back it comes! I think I need to rethink my vocal booth idea!!!

My "acoustic panels are auralex sonolite panels

Great! They should be fine, but they are only one inch thick. Not much good for deep bass trapping. I'd use those on side walls, but you'll probably need something more substantial for bass traps and first reflection points.

The speaker stands have a rubber pad between the base mount and desk then the same between the wooden panel and top of the stand arm. On top of the wooden panel are Auralex MOPAD's. I kinda want to keep this BUT you are swaying me

Then let me see if I can do a bit more swaying! :) With your speakers set up like that, you are undoubtedly getting reflections off the desk surface right into your ears: Comb filtering and phasing issue there, for sure. Plus, you cannot move your head at all with your speakers set up on their sides, and that close to your head. Even a slight movement is going to cause your ears to hear the woofers and tweeters differently, with different timings and different angles, etc. Your sound stage and EQ will only be accurate with your head placed in the exact center, and perhaps held there with a neck brace... ( :) ) It is far better to have your speakers set up vertically, tweeter over woofer. The human auditory system is very, very sensitive to horizontal spatial location, and rather insensitive to vertical spatial location. That's why if you hear an aircraft in the distance, you can close your eyes and easily identify which direction it is just from sound, but you cannot identify how high it is. The reason is simple: our ears are on the SIDES of our heads, so we get several different types of auditory clues about horizontal clues, but since we don't also have ears on out foreheads and chins, we just don't have much to go on to figure out vertical position. So speakers should be set up with the drivers aligned vertically, not horizontally, and especially if your head is very close to the speaker, as it is in your case. Which leads to another point: Both the ITU and the EBU recommend that the speakers should be at least 2m away, and no more than 4m. That means about six and a half feet to about thirteen feet, very roughly. That's what they recommend for studio control rooms and critical listening rooms. There are a number of good reasons for that recommendation, but I don't have time to go into them right now. With your setup, your head is less than half of the minimum distance. Which is, in turn, why you have to have the speakers at that 45° angle you show there (it looks to be around 45°). The recommended angle is 30°, which guarantees that the distance from your head to each speaker is the same as the distance between the speakers them selves, thus placing you in the perfect sweet spot, with the sound stage spreading around a 60 degree arc in front of you. Another issue with your head in close and a 45° angle is "shadowing": Your left ear is "shadowed" from the right speaker by your head, so you are not getting the full stereo image the way it should be, and ditto for the right ear/left speaker. One more issue: with your speakers set up like that, maybe a foot or so away from the front wall, you are most definitely creating an SBIR issue, with phase cancellation going on at all frequencies related to that distance. Next, your speakers are mounted too high, and angled down. That tilts the sound stage, so as you more your head forwards and backwards, you are also moving across the speaker axes. If you move your head back a bit, it is now behind the aim point, so the speakers are aimed below your ears and you are hearing off-axis sound. If you move your head forwards, you are now above the aim point, so the speakers are aimed above your ears and once again you are hearing off-axis sound. I can't find any polar pattern diagrams for those speakers, but I'm pretty sure that they have a fairly tight dispersion pattern, so the effect will be pretty large. Another issue with speakers tilted down a lot, is the pinna. Those are the little flesh blobs and folds on the surface of your ear. They cause a whole multitude of acoustic effects, which they rest of your ear and your brain use to determine where sounds are coming from, and the frequency balance of those sounds. Your brain and ears are set up to do all those fancy calculations when sound is coming from directly in front of you, on the horizon. So if the sound is actually coming from a bit above the horizon, then the angles are all wrong. the reflections and diffraction are now happening in the wrong places on your pinna, so your brain loses some of the clues it expects, and your sense of directionality and tone are degraded. So the speakers should not be above your "horizon". Rather, they should be set up so that the acoustic axis of the speaker is at exactly the same height as your ears. For most of the population of planet earth, that is 1.2m above the floor. That's the "standard" height for speakers in control rooms and critical listening rooms. There are several other issues with having your speakers set up as you do, but there's a very easy test you can do to see how bad the problem is: Play good quality de-correlated pink noise through your system, at a level of about 80 dB, and set your head in the exact sweet spot, perfectly centered. Listen carefully to how that sounds, and try to imprint that sound on your brain. Now move your head several inches in each direction (left, right, front, back, up, down). If the pink noise does not sound exactly the same as you move your head around, then you have problems with your speaker geometry. I can guarantee you that, in your case, you will easily hear the difference as you move your head around. In some places, the pink noise will sound more "hissy", in others it will sound more "whooshy". In some places it will sound balanced and enveloping, while in other places just a couple of inches over you will clearly notice that it is louder on one side than the other, or even "skewed" or "tilted". After each time you move your head, put it back in the center and let your brain get accustomed to how it should sound again. And add in one more test: With your head back in the perfect center, hold it in the same place, but rotate it left and right. It will sound louder / softer on each side as you do that, and the image will seem to shift to another place, as though it is no longer coming from the front center. Now tilt your head up and down, and listen to the changes there again. And finally, lean your head over from side to side, once again listening for the changes... Still convinced your speakers are set up properly? :) Those are all artifacts from having your speakers above the desk, too close, too high, angled too far down, and toed in too much. If you really want to convince yourself, then temporarily move your speakers on to stands, take away the desk completely, and set things up as I outlined in my previous post, with just you, your chair, and the speakers in the room (no desk). Now repeat the exact same tests... :) Swayed yet? :) (If not, then let's talk about REW...) - Stuart -

Genius!! thanks so much - swayed and understood!!! done deal Ok - attached is a newer design. Changes are .... 1. no sloping 3rd wall 2. new wooden frame wall with R13 and 1 layer drywall added in front of but not touching the garage door - 3. vocal booth concept changed - it's now smaller and it's now just a "private performance space" and storage. We'll use headphones for the engineer and "artist" during recording - what we've done to date. This means we save on door and isolation costs and patch bay. I'll treat it with more auralex panels and we use a prime acoustic voxguard behind the mic when doing vocals. We can store a "wall on wheels" in here that will match the opposing wall and that we can wheel out when doing mixing. 4. cloud added 5. rear wall behind sofa will have 3 x (2' x 4' x 4") panels mounted away from the wall slightly - these can be open backed if desired (ATS acoustics) 6. main front superchunk bass traps larger - about 26" wide and 8' tall 7. rear bass trapping in corners = existing auralex LENRD bass traps - 3 per corner = 6' high x 18" wide 8. speaker mountings to be tried as per you suggestion - with and without carpet to see the difference. Rest of floor will be concrete 9. quiet oscillating tall fans in 2 corners to keep air moving QUESTION: Skylight .... sooo, if my roof/ ceiling is approx. 7" thick (shingle/ plywood/ wood frame with R13 then 1 layer drywall) - how about if I buy 2 glass panel sealed window units mount then 7" apart ("on top of each other with a gap") in the roof? great idea :))??? LASTLY, please give me any input on the "silly things" we miss - that is, how to really seal the room and anything else you think I have overlooked Thanks a million - massively appreciated :)

Great! Looking much better!

2. new wooden frame wall with R13 and 1 layer drywall added in front of but not touching the garage door -

Excellent.

3. vocal booth concept changed - it's now smaller and it's now just a "private performance space" and storage.

You could still have kept that the same as it was: just adding the extra wall on the left of the control room is all that you really need. You could increase the isolation of that booth by using RC (Resilient Channel) and drywall on the inside. And if budget is an issue, then that could even be added at a later stage, as funds permit.

We can store a "wall on wheels" in here that will match the opposing wall and that we can wheel out when doing mixing.

Any reason you don't want to make that permanent? It won't be easy to build something that big on wheels, and still build it substantially enough as to do the job. In fact, the wall doesn't need to go as far back as you show: probably half of that would be enough, which would make it possible to build a permanent structure, I think.

4. cloud added

Excellent! But I would make it bigger than that. Two of those, side by side would be about right. Also, when you hang them, tilt them a bit (maybe 10° or so), lower down towards the front wall and a bit higher towards the rear.

5. rear wall behind sofa will have 3 x (2' x 4' x 4") panels mounted away from the wall slightly - these can be open backed if desired (ATS acoustics)

Definitely open backed: the sound waves need to have free passage to pass through the absorption, bounce off the wall behind, then pass back through again, on the return journey: The idea is to absorb twice, not once, and the reason for spacing away from the wall is also to put the absorption at the position of the waves where it can be most effective. At least 6" away from the wall would be good. More if you can spare the space. Also, I would use thicker insulation: 4" is OK, minimally, but 6" would be much better. They don't need to be manufactured panels either: you can build them yourself for a LOT less money than buying them ready made. Just a simple wooden frame with a panel of OC-703 inside, and fabric stretched across the front is all you need. All of those are materials you can purchase at any decent hardware store.

6. main front superchunk bass traps larger - about 26" wide and 8' tall

Good, but once again make them even bigger if you can: 36" across the front diagonal would be decent. 26" is OK, but marginal.

7. rear bass trapping in corners = existing auralex LENRD bass traps - 3 per corner = 6' high x 18" wide

I would definitely add some more there: A full sheet of 703 in front of those, diagonally across the corners. It is a small room, so it will need LOTS of bass trapping. The LENRDS are good, but you'll still need more than that for a top-class room.

8. speaker mountings to be tried as per you suggestion - with and without carpet to see the difference. Rest of floor will be concrete

Hmmmm... sounds like I need to do some more swaying here... Carpet=bad, concrete=good, carpet=bad, laminate flooring=good, carpet=bad, hardwood floor=good, carpet=bad, linoleum flooring=good, carpet=bad. Did that work? :) If you are concerned about reflections off the floor in front, then if you position the desk carefully you can block those, and also put absorption on the front of the desk (side facing the speakers) as well as underneath the desktop (in places where it won't bug your knees). You could even add a horizontal bass trap across that floor/front-wall corner, to maximize effectiveness.

9. quiet oscillating tall fans in 2 corners to keep air moving

Emmmmm.... that's not an HVAC plan. You are still not getting FRESH air into the room, nor exhausting stale air out of it. You need to move hundreds of cubic feet per minutes into and out of the room: fans do not do that, and neither does the mini-split. The min-split will do a good job of cooling and dehumidifying, but it does nothing at all to ventilate the room. That can only be accomplished with ducts and silencers. The ducts have to penetrate both the inner-leaf and outer-leaf in order to move air between the inside and outside of the room, which is why you need the silencer boxes: They retain isolation.

if my roof/ ceiling is approx. 7" thick (shingle/ plywood/ wood frame with R13 then 1 layer drywall) -

Ooops! :) You don't have any isolation up there! That will get yo maybe 30 dB or so of isolation, tops. Not much at all. I would suggest removing that drywall, spanning the underside of the trusses (or joists, depending on how it is built) with RC, then attaching two layers of 5/8 drywall to the RC. That will greatly improve the isolation.

how about if I buy 2 glass panel sealed window units mount then 7" apart ("on top of each other with a gap") in the roof? great idea :))???

Ummmm.... not so much... :) Window units are not meant to be installed horizontally or at an angle: they are meant to be installed vertically. If you try to install it horizontally, the very first time it rains, the unit will fill up with water on top, and you'll have a little fish pond up there: the glass is not flush with the surface, so water / snow / dirt / leaves will accumulate in there. Ugly, unsafe. Rather, get a proper glass skylight unit for the outside, then get a simple pane of glass for the inside, and mount it yourself in a proper decoupled frame. That frame cannot directly touch the trusses / joists, of course, so you'll have to figure out how to support that on isolation mounts. But overall, it's looking good! - Stuart -

Hi Stuart Amazing input again - very exciting and thanks 1. ok no carpet! 2. great solution for the roof/ ceiling 3. skylights are bye bye 4. ventilation - we are trying to avoid breaking the outer wall stucco shell due to the cost of repair to it so this might not be possible but I have asked my contractor 5. clouds - ok 6. front bass traps - bigger 7. likely to build the room with bass traps installed by contractor and current sound treatment then spend another weekend afterwards with a local carpenter to build the bigger bass traps in the rear corners/ clouds and rear wall trapping once I am in BTW, the reason I am trying to leave that left side open (hence moving wall idea) is that I want a "workshop" feel with some openness - part of the reason for this build at all is that my current studio means I have no daylight or feeling of the outdoors much of the day so I want to be able to sit at my piano and look out on to the garden, see my dog play etc while not doing anything loud and then close it up to get serious at mix and critical listening times - its a lifestyle choice ! thanks again Gareth

Question ..... Roof/ ceiling my contractor thinks that adding Resilient Channel to the roof joists then 2 layers drywall is gong to be expensive and he instead was thinking of building a second frame to expand the current roof joint depth to allow about 7-8" of R13 fill then doing a single layer of drywall. I'm guessing that this 2nd frame would touch the existing frame BTW. Any thoughts on the effectiveness of this please?

Well, I guess it all boils down to how much of "The goal is to build a simple and as sound proof as possible studio" you really want! :)

... he instead was thinking of building a second frame to expand the current roof joint depth to allow about 7-8" of R13 fill then doing a single layer of drywall.

I don't see how that is going to get you as sound proof as possible" without decoupling and enough mass. How is he planning to decouple that from the trusses / joists? Isolation hangers for that would be rather expensive, as compared to RC-1. And why does he want to waste eight additional inches of precious ceiling height? That's going to bring the ceiling down to 7'4" at the walls, without even considering treatment yet. If you might happen to need bass traps in those corners (wall/ceiling), which is very likely, then you'll be getting close to just 6 feet of headroom there. At a rough guess (I don't have time to do the calculations right now), with his plan you'd be getting maybe 30-something dB of isolation, tops, with MSM resonance way up at around 40 or 50 Hz, as compared to more like 45 dB of isolation, with MSM resonance below 40 Hz, using RC-1 plus 2 x 5/8" drywall. Those 8 inches of extra insulation will do very little to improve isolation. Contrary to popular belief, insulation does NOT isolate, by itself. It can be used very effectively as part of a tuned, fully decoupled, resonant MSM isolation system, yes, but by itself is pretty useless. And without decoupling, all of the advantage is out the window anyway. Why does he think RC is going to be so expensive? A quick check on-line shows 8 foot lengths of RC-1 cost around US$3.50, and an 8 foot length of 2x8 ceiling joist costs around US$5.00. Considering that you'd need FEWER linear feet of RC-1 than you would of 2x8 joists, how can it possibly be cheaper to frame that out instead of using RC? I don't get it. Does he even know what RC is? I'm just not understanding his reasoning at all. How much experience does he have in building acoustically isolated studios? If he is concerned about safety (a valid concern), then it would only cost a few dollars more to switch to RSIC clips plus hat channel, or Whisper clips plus hat channel, which are better from that point of view and would also give you even better isolation, and still be cheaper than adding a whole bunch of 2x8 lumber. Not to mention the weight factor... What does your structural engineer say? Can your roof structure handle the extra dead load of all that wood plus all that drywall? I'm just not seeing the logic here. Sorry. Maybe you can get him to explain what he sees as the acoustical advantages of a coupled structure with low leaf mass, over a decoupled structure with high leaf mass. - Stuart -

ahh .... I see - I kinda figured as much but now you have said it, I believe what I was thinking!! thanks again

can you point me in then direction of what "staggering the joints" means and how it applies to my walls and ceilings, and more importantly, do I need it in my particular case and if I do .... how do I do it?? I sweat some new grey hair appeared today :)

Staggering the joints between layers means that you move the sheets of drywall over by one stud in the second layer, so that where the joint occurs between two adjacent pieces of drywall in the first layer, there is no joint in the second layer, and vice versa. So assuming you are using standard 4' x 8' drywall laid vertically, you just slide the entire second layer across by 2', so that the joints are in totally different places. In other words, the joints on the first layer don't line up with the joints on the second layer. Another option is to hang the first layer vertically (panels turned to be 8 feet tall, and side by side), and the second layer horizontally (panels turned sideways to be 4 feet tall, one above the other). Not sure if that's a good explanation or not! If not, I'll do a quick diagram to make it more clear. - Stuart -

Time for the silly questions ...... 1. mounting electrical boxes etc : so due to budget and not being able to afford to run conduit all around the inside of my room, I am going to have to have a small hole in the upper ceiling for the light fixture cable to come through which will be sealed as best possible with acoustic sealant/ putty. I can mount the outlet boxes on the drywall but I am confused as exactly how to do this. I don't want them drilling holes through the drywall so how do you attach these and the overhead light dimmer switch to the walls?? 2. how do you mount art and acoustic panels if you can't drill through the drywall and can't attach to a stud in the wood frame? 3. I have 3 beams running across the room which are obviously attached to the existing outer leaf structure - I assume that the drywall inc. ceiling drywall can't touch these beams at all? my concern right now is not the walls as much as it is the ceiling and getting that right! attached are 3 pics of the garage pre-everything : lots of old electrical to rip out and stuff to remove !!

ahhhh .... staggering the joints I get now completely! I thought it had to do with the framing INSIDE the new wall construction! thanks

Attached is my understanding of how this whole thing looks from the side view - please tell me by yelling loudly if I am missing something as I'll be able to hear you if its not sealed right!! :)) Center light fixture - I had thought of hanging a fancy fixture BUT will consider a "track" type system on one of the beams if we think that will be better - perhaps this could be done through conduit?

URGENT!!!! Corners behind my bass traps - can I have a right angle (90 degrees) in the corners where I am building my super chunk bass traps and then splay the wall at 6-8 degrees after that? the reason is to not waste materials and make construction easier - my thought is that this IS ok as the absorbing will be in the corners through the bass trap and the 6-8 degree splay will take care of reflections outside of the bass traps .... OR ...... do I have to get rid of the 90 degree corner for the 6-8 degree splay to have any effect - what do you think folks?? aerial jpeg idea attached - the bass traps will be 36" across the front of them THANKS :))))

URGENT!!!! Corners behind my bass traps - can I have a right angle (90 degrees) in the corners where I am building my super chunk bass traps and then splay the wall at 6-8 degrees after that? the reason is to not waste materials and make construction easier - my thought is that this IS ok as the absorbing will be in the corners through the bass trap and the 6-8 degree splay will take care of reflections outside of the bass traps .... OR ...... do I have to get rid of the 90 degree corner for the 6-8 degree splay to have any effect - what do you think folks?? aerial jpeg idea attached - the bass traps will be 36" across the front of them THANKS :))))