Hi everyone....
I have been reading up on the site to get up to speed. My contractor is starting in two days and I think I have some problems to work through on my original plan.
I did start another thread but I think that thread can go away (sorry, mods feel free to delete my other thread in the construction forum).
Sooooo....
- I am building out a drum room and a control room in two adjacent / connected smallish bedrooms in my home. Drawings attached.
- There will be a pair of heavy wood / glass doors between the control room and drum room. I am not extremely worried about isolation between the drum room and the control room other than the effect that is going to have on the total isolation of the drum room from the rest of the home / outside the home.
- The home is an upside down ranch so the bedrooms are in the basement. The area is pretty dry. It's not like a damp leaky basement or anything, it's a real living area on a concrete slab partly below grade.
- I don't need a ton of isolation in the control room. I mix at low volumes and we don't have neighbors too close by. The mix room just needs as even a frequency response as possible.
- The drum room needs to be as isolated as I can get it to be. I didn't think this was going to be a problem until I started doing some testing earlier today.
- There are a pair of exterior windows in each room.
- I am thinking of doing a room within a room for the drum room.
- Two walls of the drum room face internal rooms with drywall over studs. One wall in the drum room is a cinder block wall facing a 2 car garage. The last wall in the drum room faces the outside. This wall is mixed construction, the portion below grade (about 3 feet tall) is a cinder block foundation wall covered by exterior brick. The rest of the wall is drywall / insulation / exterior brick.
- Both rooms have 8 foot ceilings (however one part of the drum room is probably more like 7 feet where a closet used to be).
- The control room is 11' 8" x 10"
- The drum room is 11' 8" x 11' 11"
- The doorways in each room open to a common hallway
- Because I am in a basement below grade and on a concrete slab my flooring options are a little limited. I am going with cork because 1. it looks good 2. it's a little less noisy than laminate, 3. it's girlfriend approved.... :)
Questions
Q1. The existing walls are already covered with drywall on both sides. Putting up an inner wall in the drum room would create a 3 leaf system obviously. If I put holes in each stud bay on the inside of the existing walls would it work to take away the 3 leaf low frequency issues? If so, how large do the holes need to be and how many holes do I need?
Q2. I would like to keep the window in the drum room, it's nice to get some natural light in there if I can. Is there a solution to keeping the exterior window so I can get natural light in while still reducing sound transfer? Do I need to do a window on the inside wall? That makes me worried because no matter what I always seem to see bugs and stuff inside these window systems over time (probably poorly sealed I know). Is there a different solution?
Q3. I don't have a lot of room to work with here and I want to maximize the space as much as I can. I plan on having the inside wall in the drum room at a slight angle. I was thinking it would start out at around 3 inches from the existing wall and end up about 6 inches from the same wall on the other side of the room. Is that enough gap between the inside and outside wall? Does a 3 inch fall over a 12 foot span even worth doing?
Q4. I was thinking of doing inside out walls in the drum room. How can I get enough mass on these things? I looked around and had a hard time finding some photos in the construction forum on how to do this. Is there a thread or some directions on how best to handle the building of inside out walls?
Q5. We live in Pittsburgh PA. It gets pretty cold in the Winter and pretty hot in the Summer. I am worried about condensation and moisture buildup between the new drum room walls and the existing walls. The exterior walls do get pretty cold in the Winter. What do I do here to prevent condensation? I assume I need to install a vapor barrier on the outside of the inside wall (if that makes sense)?
Q6. Again, I don't have a lot of space and only 8 feet of ceiling height. I plan on putting joists from one side of the room to the other then hanging sheetrock. Has anyone come up with a way to do this as an "inside out" kind of construction to put the drywall above so I can use 705 or something in the joist bays? It would save some room if I could do that.
Q7. On the inside out walls, what do I put under the walls to try and limit the coupling between the walls and the floors?
Q8. Is is really worth doing RC on the inside walls and how do you even do this with an inside out wall design? How do you caulk the bottom of the wallboard?
Q9. I think it would help to do a pair of sliding doors between each space but I want one set to be decorative (it's a girlfriend thing again). What's the best solution for doors between the drum room and the control room?
Q10. Is there a drawing out there that would work as a starting point for me on the drum room within a room idea?
THANK YOU in advance for any help here. I am pretty stressed because I have a serious time crunch so any help would be very appreciated.
New Studio - Need lots of help ASAP
Originally posted at johnlsayers.com, topic 19525.
:shock: :!: I would strongly, strongly suggest that you call your contractor and postpone the entire build until you actually have a plan. There's no way you can design everything that needs to be designed in 2 days. Not trying to scare you: just stating the truth.My contractor is starting in two days and I think I have some problems to work through on my original plan.
You should start by putting a number to that. As in "I need at least 50 dB of isolation for the drum booth to the outside world, and 40 for the control room": Or whatever the number turns out to be after you measure them. You'll need a sound level meter for that. If you don't have that number, then there is no way to decide what to build, how to build it, or what materials to use.- The drum room needs to be as isolated as I can get it to be. I didn't think this was going to be a problem until I started doing some testing earlier today.
You pretty much have no choice, if you need to isolate drums. The only alternative to that is to extremely massive walls, as in 1 couple of feet of reinforced concrete. Thankfully, "room-in-a-room" is far less expensive. But it does take careful planning...- I am thinking of doing a room within a room for the drum room.
The brick walls and block walls are a good start, but you'll need to "beef up" the other walls to match that density.- Two walls of the drum room face internal rooms with drywall over studs. One wall in the drum room is a cinder block wall facing a 2 car garage. The last wall in the drum room faces the outside. This wall is mixed construction, the portion below grade (about 3 feet tall) is a cinder block foundation wall covered by exterior brick. The rest of the wall is drywall / insulation / exterior brick.
You are aware that you'll be losing many inches of room height, for the new inner-leaf ceiling? Assuming that you can get by with 2x8 joists (that's just an example: only a qualified structural engineer can tell you for sure), allowing for an inch of clearance and 3 layers of 5/8" drywall, you'll be losing close to 10 inches of height. It might be possible to reduce that, either by "inside out" construction, or by "interleaving" the new joists with the old, but you'll still lose several inches.- Both rooms have 8 foot ceilings (however one part of the drum room is probably more like 7 feet where a closet used to be).
That's practically square! There will be pretty wild modal issues with that room. It will need a lot of treatment.- The drum room is 11' 8" x 11' 11"
The also both appear to open inwards, towards the rooms. In order to do "room-in-a-room", you'll have to invert the sense of those doors, so they open towards the hallway, not towards the rooms.- The doorways in each room open to a common hallway
Cork is fine. Not ideal, since it is soft and not too reflective but it will work.I am going with cork because 1. it looks good 2. it's a little less noisy than laminate, 3. it's girlfriend approved....
Well, you could cut holes, but they'd have to be large, and you'd be wasting all that useful drywall. A much better plan is to take off the drywall carefully, cut it into strips that fit between the studs, and use it to beef up the mass on the other side of the wall, from within, between the studs.Q1. The existing walls are already covered with drywall on both sides. Putting up an inner wall in the drum room would create a 3 leaf system obviously. If I put holes in each stud bay on the inside of the existing walls would it work to take away the 3 leaf low frequency issues? If so, how large do the holes need to be and how many holes do I need?
Yes you do need a second window on the inner-leaf wall, and you also likely need to replace the window on the outer-leaf wall with a fixed pane of thick laminated glass (just like the pane for the inner-leaf). They both need to be sealed in place properly, totally air-tight.Q2. I would like to keep the window in the drum room, it's nice to get some natural light in there if I can. Is there a solution to keeping the exterior window so I can get natural light in while still reducing sound transfer? Do I need to do a window on the inside wall? That makes me worried because no matter what I always seem to see bugs and stuff inside these window systems over time (probably poorly sealed I know). Is there a different solution?
Why? There's no need for that. The only reason to splay a wall in a live room is to kill flutter echo, but there are better ways of doing that if space is tight. Splaying walls eats up space. The minimum splay angle you'd need is 12°, which could be done with 6° on each wall, or 3° on one and 9° on the other, or any combination you like.Q3. I don't have a lot of room to work with here and I want to maximize the space as much as I can. I plan on having the inside wall in the drum room at a slight angle.
The gap inside the wall (between inner leaf and outer leaf) is calculated using the equations for MSM resonance in 2-leaf walls. It is calculated such that resonant frequency is at least 1.414 times lower than the lowest frequency you need to isolate, and preferably 2 times lower. You can't just guess here: the wall is a tuned system, and has to be designed correctly to do the job. The other option is to over-build it greatly without doing any math, and that will work, of course... except that you'll spend way more money and time than you need to. In other words, the gap needs to be figured out correctly. 3 inches might turn out to be more than you need, or at the other extreme, 6" might turn out to not be enough. You can't guess.I was thinking it would start out at around 3 inches from the existing wall and end up about 6 inches from the same wall on the other side of the room. Is that enough gap between the inside and outside wall? Does a 3 inch fall over a 12 foot span even worth doing?
The same way as for a conventional wall: with multiple layers of drywall. That makes the wall extremely heavy, of course, so it will be a major challenge to lift it into place. And dangerous too: you'll need to have several safety braces in place at all times, to prevent that thing falling. If that comes down on you, ... well it won't be pretty.Q4. I was thinking of doing inside out walls in the drum room. How can I get enough mass on these things?
correct. For cold climates, the vapor barrier goes on just before the drywall for the inner-leaf.Q5. We live in Pittsburgh PA. It gets pretty cold in the Winter and pretty hot in the Summer. I am worried about condensation and moisture buildup between the new drum room walls and the existing walls. The exterior walls do get pretty cold in the Winter. What do I do here to prevent condensation? I assume I need to install a vapor barrier on the outside of the inside wall (if that makes sense)?
Yes, there are ways of doing that, and I have designed a few rooms done exactly like that: But you can't design that in 2 days. Sorry. You also need to hire a structural engineer to tell you what size joists you need: you can't guess here either. Span tables can give you a rough idea, but the only one who can say for sure, and then sign the paperwork to back it up, is a qualified structural engineer.Q6. Again, I don't have a lot of space and only 8 feet of ceiling height. I plan on putting joists from one side of the room to the other then hanging sheetrock. Has anyone come up with a way to do this as an "inside out" kind of construction to put the drywall above so I can use 705 or something in the joist bays? It would save some room if I could do that.
Nothing! You don't need to decouple the walls from the floor, unless you need extreme levels of isolation. In that case, you need to "float" your walls, which involves a whole new set of calculations: you need the right type of rubber, and the right thickness, and the right dimensions so that it deflects to the exact right percentage when loaded with the full weight of the walls plus ceiling plus treatment plus electrical plus HVAC. If you get that wrong, then the wall doesn't float, and is not decoupled. So if you overestimate the weight, then the rubber is compressed too much, bottoms out, and does not float. If you underestimate the weight, then the rubber is not compressed enough to "bounce", so it "tops out", and the wall does not float. Lots of calculations going on to get that right... So just bolt the sole plat to the floor in the normal manner, with anchor bolts. And don't forget to seal that really well! Any gaps under the wall will greatly reduce your isolation. Even tiny gaps....Q7. On the inside out walls, what do I put under the walls to try and limit the coupling between the walls and the floors?
If you are doing a separate frame for the inner leaf, then you do NOT need RC AT ALL! The purpose of RC is to decouple. The purpose of building a separate frame is to decouple: Why do both? If it is decoupled, then it is decoupled! Doing it a second time is pointless.Q8. Is is really worth doing RC on the inside walls and how do you even do this with an inside out wall design?
Sliding doors would work very well in there. They don't take up space by swinging into the room, and the room is so small that there's no room for that in any case. So sliding doors are your best option. But not just any sliding doors! You can't use the typical "patio doors" that you buy in Home Depot. You need proper acoustic-grade sliding glass doors, that are fitted with thick, heavy laminated glass. Not cheap, but they are the best solution for your situation.Q9. I think it would help to do a pair of sliding doors between each space but I want one set to be decorative (it's a girlfriend thing again). What's the best solution for doors between the drum room and the control room?
Probably not. All rooms are different, and the room that somebody else will likely not be what you need. Rooms usually need to be designed individually, especially when high levels of isolation are needed. What worked for another guy very likely won't work for you, because your room has different requirements, and the existing structure is built differently from what he had. That said, there are numerous threads here on the forum about building drum booths. The only one that comes to mind off hand, is the sad story with a happy ending, of forum member "Beeros", in Greece: viewtopic.php?f=2&t=17363 A very interesting, and very worth-while read.Q10. Is there a drawing out there that would work as a starting point for me on the drum room within a room idea?
The only way to fix that is to make it go away: call off the contractor until you are ready to build. Proceeding in this state, with no plan at all and just 2 days away, is insane, and pretty much doomed to failure. I know you don't want to hear that, but it's the truth. You are nowhere near ready to build anything. They sane, smart thing to do is to postpone until you have the plan in place. Either that, or over-build everything massively, and hope for the best: but that will be pretty expensive.... - Stuart -THANK YOU in advance for any help here. I am pretty stressed because I have a serious time crunch so any help would be very appreciated.
Okay first off
THANK YOU SO VERY MUCH Stuart!
Some of my replies below are going to look like I am not listening to you but that's not the case at all. I really respect the information that goes on around here (including from you) and I really appreciate your feedback so thank you again.
I completely agree... however there are a few drivers here that are out of my control. I need to move a little faster than some random number of weeks or months down the road. I need to come up with the best solution I can and that might entail using the best guess method for some of the elements here. Above all, the room needs to be safe. I do a lot of construction, my contractor does as well obviously and I have been working with the same structural engineer for a few years now. Meaning, I know what I am up against and at least I have a good team. :) After the safe part, I want to create the best room I can create but I can only do so much planning. I simply can not take months and months to sit and think about this. Again, there are a number of drivers here that are out of my control. I just need to do the best I can following as many "best practice" guidelines as possible. And I do NOT want to trivialize the work but at some point it still only comes down to 4 walls and a ceiling. The laws of physics are the laws of physics and my hands are tied with such a small room. I just need to work out the details for this room as best as I can using the most tried and true best practice methods that I can afford / fit into the space. Again, not trying to trivialize what I am up against here. I just see it as a fairly simple set of not great options. I am building a room within a room. It's a small room. I only have a limited number of ways I can accomplish this. I don't want to spend $20,000, I would like to get away with considerably less than that. I don't have a budget exactly, I just know I am not going to sink ten's of thousands of dollars into something that's never going to be much better than a slightly usable space. It's never going to sound great in there, I just hope to get it to sound better than "flat out bad".. and I would like to not bother my significant other or my neighbors in the process. :D:shock: :!: I would strongly, strongly suggest that you call your contractor and postpone the entire build until you actually have a plan. There's no way you can design everything that needs to be designed in 2 days. Not trying to scare you: just stating the truth.
Well, I don't have an exact number. And frankly I don't know how I would get an exact number. I have an SPL meter and I already know that drums are LOUD :shot: in the 110 - 120 db range. But I don't have any way to know what I need to knock it down to because I don't have a way to knock it down until I do the work. I see that as sort of a catch 22, I don't know how much attenuation I need until I do the attenuation. I would guess I would need 40 or 60 db of isolation to the outside world, maybe something like that to the rest of the home but not as much to the control room. Is there a good method I could use to come up with a better number?You should start by putting a number to that. As in "I need at least 50 dB of isolation for the drum booth to the outside world, and 40 for the control room": Or whatever the number turns out to be after you measure them. You'll need a sound level meter for that. If you don't have that number, then there is no way to decide what to build, how to build it, or what materials to use.
Fair enough, I do agree.You pretty much have no choice, if you need to isolate drums. The only alternative to that is to extremely massive walls, as in 1 couple of feet of reinforced concrete. Thankfully, "room-in-a-room" is far less expensive. But it does take careful planning...
Got it.. thanks!The brick walls and block walls are a good start, but you'll need to "beef up" the other walls to match that density.
Yes, my structural engineer is involved here. As I mentioned, I have been working with him for years now on various projects so we have a good working relationship and I really trust his work. And yes, I am working with him on the joist sizes. It's looking like 2x8's but I am waiting for his take on that and he is waiting for a rough design drawing from me which is sort of my next step.You are aware that you'll be losing many inches of room height, for the new inner-leaf ceiling? Assuming that you can get by with 2x8 joists (that's just an example: only a qualified structural engineer can tell you for sure), allowing for an inch of clearance and 3 layers of 5/8" drywall, you'll be losing close to 10 inches of height. It might be possible to reduce that, either by "inside out" construction, or by "interleaving" the new joists with the old, but you'll still lose several inches.
I know, it's has me a little worried yes. I am thinking of 4 x floor to ceiling stacks of Safe 'n' Sound in a frame along with a bunch of hanging 705 clouds and panels. ???? This was one of my follow up questions. I am worried about the modal problems I am about to get into. What is it going to take to make this into a usable room? Can it even be done?That's practically square! There will be pretty wild modal issues with that room. It will need a lot of treatment.
Yes, that's the plan I was working on but didn't get there yet on the drawing. Thanks....The also both appear to open inwards, towards the rooms. In order to do "room-in-a-room", you'll have to invert the sense of those doors, so they open towards the hallway, not towards the rooms.
Actually, the not too reflective thing was part of the decision process (way down on the list) because it is a little less lively due to the small room size. I am not tracking bands in here so it's just going to be me, I am not going to dent it up too much myself.Cork is fine. Not ideal, since it is soft and not too reflective but it will work.
That is a good but time consuming plan. If it's worth the time I can make that happen. I get that mass is key so I guess I will think about that. The problem is the drywall is pretty tricky to deal with in my home, it's got wire mesh in it. So on that point.... I assume you are talking about using that to load up the existing walls yes? Also, the existing interior walls don't have any insulation or anything from the 1960's. Would it help anything to put Safe 'n' Sound in the existing interior walls after I take off the drywall on one side?Well, you could cut holes, but they'd have to be large, and you'd be wasting all that useful drywall. A much better plan is to take off the drywall carefully, cut it into strips that fit between the studs, and use it to beef up the mass on the other side of the wall, from within, between the studs.
I will have to think that over to see if it is worth the cost. There is a lot of work there, I think I would need a vinyl break to do the window. It starts to be a pretty big project on it's own. I might just black out the window with some felt or something then build the insolation wall right over the window.Yes you do need a second window on the inner-leaf wall, and you also likely need to replace the window on the outer-leaf wall with a fixed pane of thick laminated glass (just like the pane for the inner-leaf). They both need to be sealed in place properly, totally air-tight.
Well, funny you should say that. So, this whole mess started because my engineer, contractor and I found a problem with the existing room from something that was under designed back in the 60's. We actually had to put in a beam with posts on the side of the room. We were able to get most of the posts into the existing walls but they do stick out about 3 inches into the room. I will probably need to splay the inside drum room walls anyway to get by these posts. I am going to need about 4 inches to clear the post on both sides of the room. Seeing as how I already have to splay the walls a bit, does it make sense to do a little more? Or is the lost space just not worth what it would take to make it worthwhile.Why? There's no need for that. The only reason to splay a wall in a live room is to kill flutter echo, but there are better ways of doing that if space is tight. Splaying walls eats up space. The minimum splay angle you'd need is 12°, which could be done with 6° on each wall, or 3° on one and 9° on the other, or any combination you like.
Well, I will go back to what I said above. I can do the math for a year or so but I don't really have the time to do that and really, the lowest note in the room is going to be a kick drum. Figure I am trying to isolate someplace between 30 and 80 Hz give or take. But, if I am reading your reply correctly, I have a problem in that every kick drum is going to be different and even the same kick drum can be tuned differently or have different drum heads and the numbers are going to change. It still seems like the answer is to just do the best you can here? Sorry, again, I know there is a lot to this but there are so many variables as well and I don't want to end up with paralysis by analysis. What's the best way to start on the air gap?The gap inside the wall (between inner leaf and outer leaf) is calculated using the equations for MSM resonance in 2-leaf walls. It is calculated such that resonant frequency is at least 1.414 times lower than the lowest frequency you need to isolate, and preferably 2 times lower. You can't just guess here: the wall is a tuned system, and has to be designed correctly to do the job. The other option is to over-build it greatly without doing any math, and that will work, of course... except that you'll spend way more money and time than you need to. In other words, the gap needs to be figured out correctly. 3 inches might turn out to be more than you need, or at the other extreme, 6" might turn out to not be enough. You can't guess.
Yeah, that sounds like it would be pretty serious stuff. So I guess I am looking at 2 layers of 5/8th drywall here then? And I think you answered my other question later on. Same as the RC, no real need for green glue between layers right?The same way as for a conventional wall: with multiple layers of drywall. That makes the wall extremely heavy, of course, so it will be a major challenge to lift it into place. And dangerous too: you'll need to have several safety braces in place at all times, to prevent that thing falling. If that comes down on you, ... well it won't be pretty.
Cool... thanks.correct. For cold climates, the vapor barrier goes on just before the drywall for the inner-leaf.
Yes, I am working with my guy on this already. I am telling him the dead load is going to be 2 layers of 5/8's drywall. Again, it sounds like I don't need to calculate RC here so that helps. I like the idea of interlacing the joists (thanks) so I am going to think about that. That said.... the space under the beam that I mentioned up higher in the thread that we just put in is around 7 feet tall. The rest of the room is 8 feet so I was thinking about resting the joists on a stud wall behind the structural beam which is about 6 feet tall then raising the joists up to 8 feet. Meaning the ceiling would have a slope to it. Seems like it would accomplish two things, take away some of the square room feel (although this probably isn't going to do much) and provide me with the most usable space. Does the slope help and what angle would be the best? I don't think I have a lot of options here but I just wanted to get your take.Yes, there are ways of doing that, and I have designed a few rooms done exactly like that: But you can't design that in 2 days. Sorry. You also need to hire a structural engineer to tell you what size joists you need: you can't guess here either. Span tables can give you a rough idea, but the only one who can say for sure, and then sign the paperwork to back it up, is a qualified structural engineer.
Makes things a little easier, nice. Got it, thanks!Nothing! You don't need to decouple the walls from the floor, unless you need extreme levels of isolation. In that case, you need to "float" your walls, which involves a whole new set of calculations: you need the right type of rubber, and the right thickness, and the right dimensions so that it deflects to the exact right percentage when loaded with the full weight of the walls plus ceiling plus treatment plus electrical plus HVAC. If you get that wrong, then the wall doesn't float, and is not decoupled. So if you overestimate the weight, then the rubber is compressed too much, bottoms out, and does not float. If you underestimate the weight, then the rubber is not compressed enough to "bounce", so it "tops out", and the wall does not float. Lots of calculations going on to get that right... So just bolt the sole plat to the floor in the normal manner, with anchor bolts. And don't forget to seal that really well! Any gaps under the wall will greatly reduce your isolation. Even tiny gaps....
Got it, thanks!If you are doing a separate frame for the inner leaf, then you do NOT need RC AT ALL! The purpose of RC is to decouple. The purpose of building a separate frame is to decouple: Why do both? If it is decoupled, then it is decoupled! Doing it a second time is pointless.
I was planning on using a pair of these.... http://www.etodoors.com/shop/product/155 We have then in other places around our home and they are pretty heavy. Do you happen to have a link to something you would recommend here instead of the above?Sliding doors would work very well in there. They don't take up space by swinging into the room, and the room is so small that there's no room for that in any case. So sliding doors are your best option. But not just any sliding doors! You can't use the typical "patio doors" that you buy in Home Depot. You need proper acoustic-grade sliding glass doors, that are fitted with thick, heavy laminated glass. Not cheap, but they are the best solution for your situation.
I am going to check that out next.... Thank you again Stuart! Very helpful replies, I really appreciate your time and thoughtful answers. You are the best.Probably not. All rooms are different, and the room that somebody else will likely not be what you need. Rooms usually need to be designed individually, especially when high levels of isolation are needed. What worked for another guy very likely won't work for you, because your room has different requirements, and the existing structure is built differently from what he had. That said, there are numerous threads here on the forum about building drum booths. The only one that comes to mind off hand, is the sad story with a happy ending, of forum member "Beeros", in Greece: http://www.johnlsayers.com/phpBB2/viewt ... =2&t=17363 A very interesting, and very worth-while read.
Okay, things are underway. At this point I have all the drywall off of the existing walls and ceiling and all the open joist / stud bays have Safe 'n' Sound installed. I am also eliminating the door into the drum room so that is going to be drywall with Safe 'N' Sound.
So I have two ideas for the inside out walls, either straight up to conserve space or splay one wall to take care of flutter echo.
Which is better?
Oh, and I plan on putting Safe 'N' Sound in all the inside out walls so I assume flutter isn't going to be a problem. But I am worried about the room being too dead so I will probably add some spaced wood to the inside out walls, meaning I am a bit concerned about flutter.
I assume the best answer in such a small space is to just keep the walls parallel but I wanted to get some opinions.
Thanks in advance.
That's OK, actually. And many people do that. As long as you understand that you won't be getting optimal results in either isolation or treatment, and also that you'll likely be spending considerably more money than you would have with careful planning.I need to come up with the best solution I can and that might entail using the best guess method for some of the elements here.
Great! Having a good contractor and structural engineer on board is really good start. Have they both done studios before? Are they aware of the difference between building a typical house, office, shop or school, and building a studio?Meaning, I know what I am up against and at least I have a good team.
Have you considered hiring a studio designer to do it for you? That will save you both time and money. Sounds silly that you'd save money by paying someone, but it usually does turn out that way... :) I'd suggest sending an en e-mail or PM to John himself, and ask him for a quote. If John is too busy (he often is) then PM me or one of the other guys that does studio design.After the safe part, I want to create the best room I can create but I can only do so much planning. I simply can not take months and months to sit and think about this.
Actually, 8 walls and 2 ceilings, for each room .... :)And I do NOT want to trivialize the work but at some point it still only comes down to 4 walls and a ceiling.
Exactly! You are so VERY right there!! The laws of physics are extremely important to acoustics. Way too many people just don't get just how important they are, so it's refreshing to see someone who does. Sound is a physical phenomena, governed by the laws of physics. There are equations for figuring out how to isolate and how to treat, how to optimize, etc. But on the same side of the coin, not using those laws to get the best possible out of your room doesn't seem smart. Even though acoustics is a science, based on physics, many people are surprised once they find out how sound actually works: it is not the way most people think it works, and is not intuitive at all. The science doesn't lie, but human guesswork does. Who would have thought, for example, that taking a wall with a sheet of drywall on each side and then adding an extra sheet in the middle, would make the isolation WORSE? Not intuitive at all. But very true, and absolutely predicted by the science of acoustics. Who would have thought that lighter, fluffier insulation would be BETTER at absorbing bass frequencies than heavier, denser insulation? Once again, totally unintuitive, but absolute fact. Who would have thought that sound sometimes acts like arrows, shooting out in straight lines, and other times acts like balloons being inflated? Once again, explained and predicted by physics, but never imagined by most people. And failing to take all of the above into account (along with numerous other factors), can mean the difference between success and failure, in studio design. Keep that thought in mind always: The laws of physics define exactly how your room will behave, from both the isolation and the treatment points of view. I'm really glad that you already understand that: It will come in VERY handy as you work though the design and construction or your studio. "Laws of physics" is the key.The laws of physics are the laws of physics ...
Right! And most of those are the wrong ways... :) There's only a few "right" ways, and even then there can be a large difference in both results and costs.I am building a room within a room. It's a small room. I only have a limited number of ways I can accomplish this.
You have about 250 square feet of floor area. You have a contractor that knows what it costs to build a square foot in your area. Ask him if it is realistic to budget $80 per square foot. It sounds about right, from what I know of studio construction costs, but you should check with him to make certain. Tell him to think about this as turning an unfinished garage into a complete home theater, or maybe a full "granny flat". I don't think you'll be able to do it for much less than that.I don't want to spend $20,000, I would like to get away with considerably less than that.
It doesn't have to be "no better than slightly usable" :shock: :!: It can be much better than that. John has built highly successful commercial studios inside shipping containers! If he can do that, then there's no reason why yours can't at least be "pretty darn good".I am not going to sink ten's of thousands of dollars into something that's never going to be much better than a slightly usable space.
All you have to do is ask! :) The answer is: You measure, and you simulate. You set up a good set of speakers inside the room exactly as it is now, and you play the typical type of music that you'll be doing once the place is finished. You play it at a level of around 100 dBC, as measured inside the room, about three feet way from the speakers. Then you walk around the house, inside and outside, noting down how loud that measures at several key points. That tells you how much isolation you already have. Then you go to the spot where you noted that it was the quietest level, and you get someone else to turn down the music slowly, until you judge that the level is acceptable for that location (either using your local noise regulations limits, or your "family and neighbor" limits), and note down that level. With the same level still playing, go back to all the other points where you noted down levels, and write down the new lower level for each location, especially the level back inside the room, three feet from the speakers. Then you go back once more to the location where you had the loudest level on the first trip around the house, and repeat the procedure: turn it down until it is acceptable, then note down the final level at all the other points too, including back inside the room. That gives you a full set of objective numbers for figuring out how much isolation you need, without guessing. And it should take you maybe ten minutes to do that. It's a really small investment of time to get the absolute most important data that you need for figuring out your entire build. Without that data, you have no idea if you are building correctly to isolate to the levels you need, or overbuilding (and thus wasting lots of money on unneeded materials and labor), or "underbuilding" (and thus wasting all your money, since the result will not meet your goals).Well, I don't have an exact number. And frankly I don't know how I would get an exact number. I have an SPL meter and I already know that drums are LOUD :shot: in the 110 - 120 db range. But I don't have any way to know what I need to knock it down to because I don't have a way to knock it down until I do the work.
That's a good guess, but it's also a huge range: Isolating to 60 dB means that you need to stop exactly one hundred times more energy as isolating to 40 dB. Laws of physics... :) dB is a logarithmic scale, and each time yo go up 10 dB, you are dealing with ten times the intensity. 20 dB is 100 times the intensity. 30 dB is one thousand times the intensity: Etc. so building a room for 40 dB when you actually need 60 dB means that you are only stopping 1% of the energy that you should be stopping... those darn laws of physics again... :) :horse:I would guess I would need 40 or 60 db of isolation to the outside world,
You might not know, but we know! :) That's why you came here, isn't it? To ask advice of people who have done this before, and know how to do it? :) 8) If you don't know something about building a studio, all you have to do is ask... That's what the forum is meant for!I don't know how much attenuation I need until I do the attenuation.
How can he determine that when he doesn't yet know what the dead load and deflection will be? :)And yes, I am working with him on the joist sizes. It's looking like 2x8's
It's a common myth that adding absorption to a room will make modes go away; it doesn't. They are still there, simply because a "mode" is a basic consequence of the room dimensions: The only way to change a mode, is to change the dimensions. What treatment WILL do is to damp the mode, so it doesn't ring too long (reduce the decay time), but the treatment has to be in the correct location for the mode being treated. For example, if it turns out that you have a major issue with your 0,1,0 mode, then putting up a wonderful cloud will do absolutely zilch to treat that mode, since it does not involve the ceiling. That's why it is important to do a modal analysis of the room in advance, adjust the room dimensions if possible to get the smoothest modal response, then treat accordingly. A hard-backed ceiling cloud at an angle, for example, can do wonders for vertical axial and tangential modes, and have a decent effect on longitudinal axial and tangential modes too, ... if designed properly...I know, it's has me a little worried yes. I am thinking of 4 x floor to ceiling stacks of Safe 'n' Sound in a frame along with a bunch of hanging 705 clouds and panels.
Yes it CAN be done, as evidenced by the rather large number of successfully completed rooms built by forum members of the years, as well as by John himself. With good design, even "terrible" rooms can be made acceptable, and rooms that are merely "not so good" can be made "pretty darn good".This was one of my follow up questions. I am worried about the modal problems I am about to get into. What is it going to take to make this into a usable room? Can it even be done?
Right, but be careful with that: it's getting close to some of the other major myths about studios: "egg crates and carpet". All of those are pretty useless for treating a studio. Egg crates accomplish essentially nothing at all (except to make it look cheap and disgusting!), while carpet does the opposite of what is needed in small rooms. Carpet absorbs a lot of highs, but randomly, some mids, tapering off down low, and no bass at all. What small rooms needs is huge amounts of bass absorption, some low absorption tapering off up higher, and no high absorption at all! That's what you never see carpet used in professional studios (or at least, you only see proper acoustic carpet used...). Cork is somewhat similar, but does have its uses in acoustics. And the general idea in studios is to keep the floor live, solid, hard and reflective, while keeping the ceiling soft, diffusive, absorptive, for psycho-acosutic reasons. Basically, that's what our brains expect, and in that type of environment, they work best at identifying sounds with the least amount of confusion. A studio with a floor that is too "soft" acoustically, provides insufficient reference for our poor old brains to be able to figure things out well.Actually, the not too reflective thing was part of the decision process (way down on the list) because it is a little less lively due to the small room size.
Mass is ONE of the keys to isolation. Without good mass, you have no isolation, but also having mass in the wrong place is nearly as bad as not having enough of it. It most certainly is worth the time to put mass in the right place, if you hope to have useable isolation!!! An isolation wall is a tuned system. You tune it by adjusting the mass on each side, and the air gap between. Get it wrong, and it won't isolate at the frequencies you want it to...That is a good but time consuming plan. If it's worth the time I can make that happen. I get that mass is key so I guess I will think about that.
Correct, but if your old drywall isn't up to the job, then just use new stuff without those wires in it.The problem is the drywall is pretty tricky to deal with in my home, it's got wire mesh in it. So on that point.... I assume you are talking about using that to load up the existing walls yes?
It's not just that it would help: it's that it is critical to do so! As I said before, a wall is a tuned system, and it works on the exact same principles of physics as the suspension of your car, which is also a tuned system. The drywall on either side of it is equivalent to the mass of the car on one side and the mass of the wheel on the other side, the air is equivalent to the spring, and the insulation is equivalent to the shock absorber. You can imagine how well your car rides with no shock absorbers.... That's exactly how well your wall will isolate without insulation in it. Just as shock absorbers damp the very low frequency resonance of a car's suspension, so too porous fiber insulation damps the resonance of an isolation wall. And as you so correctly pointed out, this is all governed by the laws of physics, and all needs to be calculated for YOUR wall, not guessed. Just as you cannot use the shock absorber from a Ferrari on a Mack truck, or the spring from a locomotive on a Toyota, so too you cannot just slap in any old mass on either side of the wall, or any old air gap, or any old bit of insulation. It has to be done right, based on the physics, calculated with the equations: Either that, or chosen from among the set of empirical test walls that have been tested in laboratories, and whose properties are known.Also, the existing interior walls don't have any insulation or anything from the 1960's. Would it help anything to put Safe 'n' Sound in the existing interior walls after I take off the drywall on one side?
Well, "blacking it out" will work fine for visuals, in the sense that you won't be able to see through it any more, but that will do essentially nothing for the isolation: a piece of felt won't even be noticed by the sound waves, as they pass right through it...I might just black out the window with some felt or something then build the insolation wall right over the window.
Not really. As long as the air gap inside the wall is big enough to do the isolation job that you want it to do, as defined by the equations that you calculate to make sure it will do it... :horse: :roll: :wink: then that's all the gap you need. Making the gap bigger than that will bring down the MSM resonant frequency even lower, which is good, but if it is already low enough to accomplish the job (as shown by those calculations.... :) then making the gap bigger is just wasting space.I will probably need to splay the inside drum room walls anyway to get by these posts. I am going to need about 4 inches to clear the post on both sides of the room. Seeing as how I already have to splay the walls a bit, does it make sense to do a little more? Or is the lost space just not worth what it would take to make it worthwhile.
Then hire someone to do it for you! :shock: John's fees (and the fees of other designers too) are a lot more reasonable than you might think, especially when you take into account the amount of money you can potentially waste by guessing wrong, and what you can save by having them get it right...Well, I will go back to what I said above. I can do the math for a year or so but I don't really have the time to do that
Equation for Mass Law, which tells you how much isolation you will get from a single leaf of mass (such as a brick wall) TL = 20 log (Ms x f) – 34 dB where: Ms = Surface Mass (lb/ft2) - F = Frequency Plug in the numbers, assuming that your "leaf" consists of two layers of 5/8" drywall: TL = 20 log (5 x 80) – 34 dB = 18 dB (that's for 80 Hz) TL = 20 log (5 x 30) – 34 dB = 9.5 dB (that's for 30 Hz) Oh dear. Your wall won't work too well for drums. And the math doesn't take months to do! Clearly, mass law ain't your friend here! So single leaf is out of the question. Two-leaf, on the other hand, does make sense. But the equations are a little more complex: TL = 20log( f (m1 + m2 )) - 47 when f < f0 TL = TL1 + TL2 + 20log(fd) - 29 when f0 < f < f1 TL = TL1 + TL2 + 6 whem f > f1 Where: m1 and m2 are the surface masses of each panel d is the depth of the airspace between, f0 is the mass-air-mass resonance frequency f1 is equal to (55/d) Hz. TL1 and TL2 are the transmission losses for the individual panels calculated from the mass law equation above. So, since a two-leaf wall (in other words, a "room in a room" studio) is a resonant system, then there are three different types of isolation going on: below the resonant frequency, in the range of the resonant frequency, and above that range. Once again, if you do the math (or hire someone to do it for you), you will easily see that getting it wrong means that your 30 Hz to 80 Hz kick will either not be isolated at all, or even worse it will actually be amplified by your wall, or best case (if you get really luck and guess the construction right!), then it will be nicely isolated. Your chances of guessing right are pretty slim... :)the lowest note in the room is going to be a kick drum. Figure I am trying to isolate someplace between 30 and 80 Hz give or take.
so just tune the wall to have its MSM resonance at least 1.414 times lower than the lowest kick you intend to use! And build it so that it will provide the number of dB of isolation that you need at that frequency! It's not rocket science. The math isn't that hard.But, if I am reading your reply correctly, I have a problem in that every kick drum is going to be different and even the same kick drum can be tuned differently or have different drum heads and the numbers are going to change.
I do agree that the answer is to "do the best you can", but I don't agree that "taking a wild guess and hoping fervently" is the same as "doing the best you can". I'd suggest that "figuring it out using the laws of physics" is closer to "doing the best you can".It still seems like the answer is to just do the best you can here? Sorry, again, I know there is a lot to this but there are so many variables as well and I don't want to end up with paralysis by analysis.
By using the equations above: :shot: If your air gap is not big enough, then your MSM resonant frequency will be too high, within the range of the kick drum, and therefore your wall will actually amplify the kick drum. (not just fail to isolate, but actively amplify). It can do that, because it is a resonant system. And just like resonance can destroy a bridge or a building though amplification of a small input, so to it can easily multiply your kick drum sound through the wall...What's the best way to start on the air gap?
Here too, you tune your wall by setting the right amount of mass on each leaf. Too little mass, and the MSM resonant frequency will be too high, ... amplification, destroyed bridges, etc... There's an optimum combination of mass and air-gap that will get your MSM resonance to the right point.So I guess I am looking at 2 layers of 5/8th drywall here then?
Once again, that depends on how much isolation you need in the low frequency end of the spectrum. Correct, you do not need RC, but Green Glue does something different from RC, and you might well need it. Green Glue ("GG") is a visco-elastic polymer that does one thing really well; it acts as a CLD (constrained layer damping) compound in between two layers of flexible mass, such as drywall, plywood, OSB, etc. What it does is basically to damp sheer waves, which run along the surface of the panel, parallel to it: Those are major transmitters of low frequency energy, and GG is pretty good at dealing with them. So if high levels of low frequency isolation are needed, then GG is definitely a good product to consider.Same as the RC, no real need for green glue between layers right?
How do yo know that, if you didn't do the math yet? :cop: :) Also, dead load is not just the drywall: it is everything that makes up the entire ceiling structure, including also the joists, nails, GG, insulation, electrical wiring and conduit, HVAC ducts, silencer boxes, etc. It can be much higher than the mass of the drywall alone... Your structural engineer will also need to know the maximum deflection for your joists: what number did you give him for that?I am telling him the dead load is going to be 2 layers of 5/8's drywall.
A sloped ceiling is fine, and can indeed improve the room acoustics. The biggest issue is to ensure that the inner-leaf ceiling only touches the inner-leaf walls: it cannot make contact with the outer leaf walls at all: Not even a single nail. The two leaves of an MSM system must be totally independent, with no mechanical connections at all.Meaning the ceiling would have a slope to it. Seems like it would accomplish two things, take away some of the square room feel (although this probably isn't going to do much) and provide me with the most usable space.
Any slope helps! Even low angles can save space, and break up the modal response a bit. Higher angles are needed for killing flutter echo (about 12° or more) and still higher angles are needed for RFZ, NE, and CID designs. But even small angles are good.Does the slope help and what angle would be the best? I don't think I have a lot of options here but I just wanted to get your take.
Here's a couple: http://www.soundisolationcompany.com/so ... udio-doors http://www.solarinnovations.com/sliding ... lass-door/ http://www.noisebarriers.com/library/PD ... tSlide.pdf http://www.avantisystemsusa.com/product ... le-glazed/ http://soundproofwindows.com/doors.htmlDo you happen to have a link to something you would recommend here instead of the above?
:yahoo: That's what we are here for!Thank you again Stuart! Very helpful replies, I really appreciate your time and thoughtful answers. You are the best.
Did you also beef up the other side of those walls? At the risk of sounding like a broken record: if you didn't do that then you won't get high levels of isolation. You wont even get good isolation, for the type of situation you described. At this point you can still fix that: Pulling out the insulation, beefing up the other side, then putting the insulation back in again can still be done very easily. But this is your last chance to do that. Once the inner-leaf is in place, then all bets are off and you are stuck with lousy isolation... :? I'd strongly suggest that you should NOT blow this opportunity: it is no exaggeration at all to say that the success or failure of the isolation depends entirely on this point. Blow this one, and NOTHING that you do later can make up for it. Nothing. If your outer-leaf is lousy, then no matter how good your inner leaf is, the final outcome is lousy. "Laws of physics", and all that... :) Think of it in visual terms: for someone with poor eyesight who wants to see out into the garden, it doesn't matter how good their glasses or contacts lenses are, they will never be able to see out if the window is filthy. The best contacts and most expensive spectacles in the world can't to anything to fix the lousy visibility through the window. Whereas if you first spend some time just cleaning the window, then even mediocre contacts will allow great vision.... So I'd really, really, REALLY suggest that you "clean the window" so to speak, by beefing up and sealing your outer leaf. It's probably the single most important thing you can do right now to increase your total isolation.At this point I have all the drywall off of the existing walls and ceiling and all the open joist / stud bays have Safe 'n' Sound installed.
Right! Your assumption is correct here. Try to maximize the room volume as much as you can, but without sacrificing the air gap that you need inside the walls to provide the isolation that you need.I assume the best answer in such a small space is to just keep the walls parallel but I wanted to get some opinions.
Right here too. Flutter is usually easily fixable with a couple of inches of suitable insulation, and you'll have more than that.Oh, and I plan on putting Safe 'N' Sound in all the inside out walls so I assume flutter isn't going to be a problem.
If you do that, then you are basically making what is known as a "slot wall", which is a tuned device: it is a series of Helmholtz resonators, each tuned to a different frequency, which is once again given by the laws of physics. The equation is fairly simple. Slot walls are usually used to treat mid-range issues in the room, and should be tuned to do that: The tuning depends mostly on slot height, cavity depth, slat width, and slat thickness. But the overall action of the entire wall also depends on "percent perforation". If that is low, then the wall acts as a series of individually tune resonators. If that is high, then it acts more like a broadband device, where the center frequency is the average of all the individual tuned frequencies. Roughly. So if you go that route (which is actually a very good idea!) then you have some more calculations to do. if you DON'T do the calculations, them there's a very real probability that you will not be treating the frequencies that do need it, and you will be treating the ones that don't need it. (Laws of physics, and also of probability and chance! :) )But I am worried about the room being too dead so I will probably add some spaced wood to the inside out walls,
The answer is "checkerboarding". And maybe also opposing diffusers, perhaps a poly-cylindrical, since the room is too small for things like QRDs, PRDs and other numeric sequence diffusers.meaning I am a bit concerned about flutter.
Thank you again and again Stuart!
So a few things...
First, I am not a complete novice here, which helps a little. I have been a professional recording engineer (or was professional, it's more of a hobby now) for a good while. I decades ago I had a number of classes on acoustics so I get a lot of the general ideas, although I have forgotten a good bit of that education. :D I have also been reading this site (and others) for years so I have some of the general stuff under my belt already. And, I have a pretty strong construction background. I have done a lot of work in that area so I know my way around a hammer. Again, I think all of this helps, I am not starting from square one if you know what I mean.
Secondly, I would be happy to pay someone for a design.... but I can't wait for weeks (or whatever) to get on someone's schedule and I imagine all of you guys are weeks, or months out for design work. This whole situation sucks because I am stuck, I really have to get things done quickly and I have to just do the best I can to make it work.
I also can't afford to pay thousands of dollars for a design. It just is what it is, we all have limitations, I am sure you understand. I don't know what a design would cost but I am not sure how much I can swing here.
And I know exactly what you are saying on the physics stuff. I am a SERIOUS follower of science. While I don't know the math involved, I know the math is there, it is real and can't be ignored because I don't like what it is telling me (I think many people miss that point in many areas of life not just studio design).
Anyway, outside of air gaps between walls and mass load on the exterior / interior walls, with such a small space, I just don't know what there is to "design"? This isn't a knock at ALL on what you guys do, I have great respect for your work (I seriously mean that). But with rooms this small I just don't know if I would get my money's worth from a true design... again, it just seems like I am stuck with a "just deal with it" solution.
That said... if you think I can get something more than "here is the air gap between inside and outside walls you should use" and "this is the amount of mass to add," and if you think someone can turn something around quickly for not a lot of money I would LOVE (and I mean LOVE) to get some help here.
In short, maybe it's a matter of finding out what I am getting for the money.
:D
That and I wouldn't really know where to start to track someone down. I guess I could PM John or just put a RFP (request for proposal) here in this thread....
Ha!
If anyone is interested in getting a design together I would love to talk about it a bit.
Thanks
That's good to know! It's always a challenge to figure out what level new forum members are at, so I tend to underestimate, in order to play it safe. Sometimes that comes across as "preaching to the choir", but I think it's the safest approach. Sorry if you felt I was condescending! Not my intention at all.First, I am not a complete novice here, which helps a little.
Here's something that might open your eyes a bit, and get you re-thinking about your space not being usable: http://johnlsayers.com/Pages/Spark_1.htm That one is actually a bit SMALLER than yours will be... :) As you can see, small spaces can be made very usable. Spark 1 is world-class, despite its size. And as you can also see, there is plenty to design in there. So how does it sound inside? Good question: Click on the video to play it, and listen carefully to the sound of the commentators voices, and the sound of the guitar: It would be pretty hard to beat that sound, even in a much larger studio. Want more evidence? Here's a link to a recording done in that studio: http://johnlsayers.com/mp3/danny_boy.mp3 Listen to those vocals, and the guitars.... All recorded inside a shipping container studio... :shock: Now tell me your place, which is BIGGER, can't sound just as stunning!... :) So is it worth investing in your place? Spending a bit extra money to design and build it right? Based on the sound and pictures of an even smaller place, I'd say the answer is an unequivocal YES!, You bet! :) Here's an even smaller one: viewtopic.php?f=11&t=4025&p=30206Anyway, outside of air gaps between walls and mass load on the exterior / interior walls, with such a small space, I just don't know what there is to "design"? This isn't a knock at ALL on what you guys do, I have great respect for your work (I seriously mean that). But with rooms this small I just don't know if I would get my money's worth from a true design... again, it just seems like I am stuck with a "just deal with it" solution.
I think the photos and recordings linked above are pretty convincing answers to those questions... :) There's a bit more too it than just air gaps and mass.That said... if you think I can get something more than "here is the air gap between inside and outside walls you should use" and "this is the amount of mass to add," and if you think someone can turn something around quickly for not a lot of money I would LOVE (and I mean LOVE) to get some help here.
See above... 8) So if you ask me, I'd say that it is well worth while going that route. ( But then again, I'm a bit biased... :) ) - Stuart -In short, maybe it's a matter of finding out what I am getting for the money.