First off I'd like to give a huge thanks to John Sayer, all of the admins, moderators, and senior members of this message board. Lots of tried and tested knowledge. I wish I had discovered it a long time ago. You guys are awesome!
Welp, … here we go….
Greetings!!
My name is Jason. (*members- "Hello Jason").
I'm a musician, performer, instructor, engineer, and producer in Alpharetta, GA, outside of Atlanta. I've been running my studio in my home producing and engineering for the past 5 years. It is small and absolutely nothing special but its been getting the job done. Work has been steady but I've been losing business due to the fact that I don't have the space to live track a full band. Business is good and it is time to expand! I'm currently building a new studio from the ground up and I would greatly appreciate all posts, comments, suggestions, criticisms, and advice that anyone would care to share because I've never designed or constructed an acoustically sound structure before. I have a background in construction so I'm not completely green, and I have my father who is a construction guru as my partner that has been helping me get the ball rolling. This has always been a dream of ours and now we finally get to do it! We are making a facility that will be a recording studio and used as a place for small live performances and rehearsal space. Our plan was to erect the basic structure (slab/masonry, basic framing, roof siding, rough utilities, etc.) since we knew we could do it cheaply by GC'ing it ourselves, and then proceed to conquer the interior build out of the studio as we gathered more knowledge and decided on our build methods. The roughing in of the building is almost complete, I've gathered my thoughts, and I think I'm finally ready to post on this forum. All comments and verbal ass kickings are welcome and appreciated! I wasn't sure if I should post this in design or construction so please forgive me if I shouldn't have posted here.
Overview:
The entire building (see pics) is about 2000 sqft (28'x64' with a 12x12' punch out on the back wall). 308sqft control room, 1180 sqft for live & iso space, and about 500 sqft for lounge/kitchen,bathroom/office. It is located on my property in Alpharetta near a somewhat noisy back road, but I have no neighbors to piss off!. Yay! I've done a complete drawing of it in Sketchup with my desired end design. I'm new to sketchup and got a little layer-crazy but the drawing is accurate to the current existing construction, -Also I cant figure out how to shrink the size of my sketchup file down to 500kb for sharing from its current size of 2.1mb... can anyone throw me a quick bone so I can resize and share?-- I haven't added the roof trusses to the drawing yet but will soon. My plan is to tackle this mammoth in sections because different parts of the building have different needs. I think I've formed a pretty good plan of action but am still indecisive and unsure on a few topics. After gluing myself to this board for the past month or so I've managed to answer a lot of my own questions, so thanks to all of you, but with so many ways to "skin the cat" its hard for me to decide what is right for my scenario. My budget for building out the interior of the studio is about $40-50K. My overall plan for the interior is to finish out the control room and lounge/bath area first so I can at least be mixing while the live half of the building is coming along. That being said, lets try to focus our posts on the control room for now. :)
CONTROL ROOM: L= 20' 6 1/2" W= 14' 3 3/4" H= 10' ceiling dropping down to 8' over the rear 4 feet of the room.
Current Status: The control room is on floor joists above a crawlspace with one layer of 3/4"plywood decking. The walls are double 2x4 walls with a 2" gap in-between. Unfortunately these walls are capped with a 2x10 due to certain structural needs of the building so they are not full decoupled from each other which totally sucks. When completed I will be outfitting the studio with a console/ workstation of some sort. Maybe an SSL AWS, but I've been toying with the Idea of making a modular tracking console out of miscellaneous outboard gear… thats a whole other post that will come out soon enough! As for monitoring I will have some NS10's, mixcubes, and dynaudio BM5a's to choose from for near-fields. As the studio grows I would like to add a pair of soffit mounted loudspeakers to the control room. Probably a pair of Augspruger GA115's with a single sub. I want to construct the soffits now but leave them covered and still working as traps until we get loudspeakers.
----- Areas of confusion: 1) acoustic design & components, 2) walls, 3) floors, 4)speaker soffits
1) Acoustic Design- When dimensioning this room, I knew how much space I needed to have a comfortable, decent sounding workspace but am still uneasy about choosing the different angles in the room and the treatment methods. After a bunch of research I think I'm close to what will work but could definitely use some help. Acoustics is a realm of the audio world that is still a bit over my head but im learning more every day. See the design pic below. On the sketchup drawing you can see that I made a rough footprint of the speaker soffits angled at 30. the front helmoltz absorbers angled at 12, and the rear absorbers angled at 6. Notice the bass trap across the back of the room that I plan to fill with hanger traps. If my calculations were correct my helmholtz's are about the size that they will need to be to help with the rooms frequency issues. I was also considering using clouds over the room and less absorption on the walls. There is a window looking into the live room on the right long wall of the CR. I know this window is in the RFZ which is a bad place for glass but am wondering if leaving it there would corrupt the sound in the mix position.
Questions for # 1 -A) is my design on the right track? Help me point out my flaws
B) Am I bat-shit Crazy? … Please take me to school on this one guys! any suggestions or comments would be a big help.
2) Walls - A few things are making my mind drift trying to settle on a wall method. Adjacent to the front wall of the CR is the hallway/air-lock leading into the live area, and adjacent to the right wall of the CR is the live area. When I'm tracking artists I'm not monitoring at high volume so the goal is more of keeping sound out rather than in. With the existing double walls of the control room being capped and coupled to each other and the floor decking (9' thick total frame) my plan was to put up another 2x4 wall from the slab to the roof trusses 6" outside the right control room wall that will be the resilient "spring" wall and barrier between the CR and Live area. With this in mind I figured I'd be fine if I constructed the inner CR walls using 4" of OC703 in-between the studs, 2 layers of 1/2" drywall glued with green glue and screwed directly to the studs, caulked and sealed accordingly. The outer spring/barrier wall will be constructed of 4"of OC703, 2 layers of 3/8" drywall, glued/caulked/sealed, screwed to resilient channel on clips. That will make out to be - Inner Leaf / 4"insulation / 12" air space \ 4" insulation \ Outer leaf on spring. If i studied correctly this will be a very effective sound barrier between the zones because its two differently constructed leafs with 12" of air in-between with one of them on a spring. I'm pretty sure that will stop any sound from the live area from getting into the control room if installed properly. If I end up turning the hallway/airlock into a vocal booth I was planning to do the leaf on the booth side with 3 layers of 3/8" drywall glued/caulked/sealed on a spring for better isolation being in closer proximity to the control room.
Questions for # 2- A) With my existing CR double walls being coupled to themselves by the 2x10 cap and coupled to the floor decking with no spring, do you think the way I intend to finish the walls will achieve my desired isolation? Am I doing to much? More/less wall mass? More/Less air space?
B) Any thoughts on working a mass loaded vinyl or audio mute material into this equation to improve it?
3) Floors - I'm gonna keep this one short since I'm pretty sure I know the answer. The 3/4" CR decking sits on 2x10 joists 2 feet above the slab below that is a crawlspace. I'm planning on adding an 1/8" layer of MLV and another layer 1/2" ply to the existing floor before the finish flooring to add mass.
I'm gonna say it…"Do I need to float my floor?" Honestly, I sure as Shit don't want to!!!
I figured that by building the barrier between the CR and live area the way I described it in #2 above that It would provide enough isolation between the sounds of the live room and the sounds of what is seeping through the floor into the crawlspace under CR. If I turn the hall into a vox booth, I would probably float the floor off of the existing decking to better isolate it from the CR if I absolutely had to.
Questions for # 3 - A) Given the crazy added costs and weight of floating floors and in my scenario. I really don't wanna float my floors.
Do I need to float my floors, and why? (please say no, please say no, please say no…)
B) Do I even need to bother adding MLV to the floor or will 2 layers of ply on some felt do the trick?
C) Would it be smart to plan on insulating the cavities between the floor joists to help with the leakage?
Again, while I'm recording clients I'm not monitoring them at 100 db. Trust me, I like to blast it just as loud as the next guy. But when I'm actually recording someone and am listening critically its not at high volume.
4) Speaker Soffits - Never done this before! Definitely need some help!
As described above, as the studio grows I'd like to upgrade to a pair of soffit mounted loudspeakers. I'd like to construct the soffits framing now and just have them operating as hangar traps covered by a cloth finishing or solid piece of ply until I get loudspeakers. Once speakers are chosen I'll remove the cloth covers or cut into the ply and rework the cavity to properly house the speakers. Good idea? bad idea?
In the end, my speakers will have to be angled down at the mix position because they will need to be more than 4' 6" from the floor. I can't figure out exactly what angle to use for the slanting of the soffits because Im not exactly sure of a good ballpark distance for loudspeakers to be from the mix position. I've worked in studios with great loudspeaker systems but never thought about how far away they were from the mix position. I know it probably varies from speaker to speaker and room to room. Right now I have it designed where the face of the soffits will be about 7 feet away from the mix position, a little over 60 degrees from phantom center and slanted at 30 degree angles off of the front wall allowing for a 24" wide, and 16" +/- deep cavity at its lowest point. I'd like the speakers to be 6' +/- high and angled down to the mix position. I've sorted through lots of posts and reference material on the soffit subject but still cant put it together.
Questions for # 4 - A) Is the idea to "rough in" the soffits now a good idea, or should I wait until I actually have the speakers i'm going to mount and then construct the soffits in what will be an existing, working control room?
Wheeeewwwhhh!!!
I just scrolled up and realized how long this post is and how it spans over several discussion categories so I hope I don't get a lashing for posting this on the wrong board, and hope I didn't break too many rules. I hope I didn't go too overboard with this first post but I've just been bottled up with questions I've been waiting to ask! Thanks to all that have taken the time to read my post. Skimming all of your posts for the past months has been intriguing and educational. Any existing threads, links, or reference material that might answer some of my particular questions would be greatly appreciated. I'll be eternally grateful to anyone who downloads my sketchup file and helps me work with my design. I also am not opposed to hiring someone more experienced to work with me directly and consult the build. Any beacons of light in all of this himiny-ha are welcome. I'm open for all questions and suggestions..
Thanks again to John and all of the senior members for their free wisdom and the time and effort they put into their posts, and keeping this board alive!
Jason
-First Post Ever - Building an AWESOME New Studio in GA!
Originally posted at johnlsayers.com, topic 18531.
Hi Jason, and welcome to the forum! :)
Great first post, by the way! That's refreshing. Way too many newcomers post things more like "Here's my square. How do I make it into a studio?". So it's great to see a first post like yours, with very complete, detailed information.
On the contrary! You did it completely right. That's exactly the type of first post that we ask for. It shows that you have already put a lot of effort into thinking things through, explaining where you are, what you want to do, asking about things that you are concerned about, etc., which is great. I'd really like to reply at length to your post, since there is so much to be said (on what you mentioned, and other aspects that you didn't mention), but unfortunately I'm totally tied up for the rest of the weekend with other commitments, so I probably won't be able to comment until Monday. But I did want to at least say "hi", and welcome you to the forum. - Stuart -I just scrolled up and realized how long this post is and how it spans over several discussion categories so I hope I don't get a lashing for posting this on the wrong board, and hope I didn't break too many rules. I hope I didn't go too overboard with this first post
Hello Stuart! ...Pleasure's Mine.
Thanks for responding and showing interest. It's literally taken me a month to gather my thoughts and work everything in to sketchup before posting anything. Glad to hear I did it right. I probably could've included more detail but felt myself getting carried away and writing a novel. :blah:
If I can add my sketchup drawing it'll probably answer most people's first typical questions. Did my best to make it dead nutz to existing scale.
Thanks for taking the time to form a response.. I don't mind waiting.
But quickly before you go... I'm sure theirs a way to shrink my sketchup down to postable size but im new to the program. Any quick tips on how to get the file up? Is it ok for me to post the file up on sendspace or other file sharing site and post the link to the download here?
Thanks!
Jason
There's a strange thing about SketchUp: when you delete something inside your model, it disappears from the screen, but the data is still stored inside the file, in case you want to then "undelete" something. So as you work on your model, creating and deleting things, the file grows much bigger than it should, due to all the unused "baggage". But you can remove that: On the "Window" pull-down menu, select "Model Info": That opens a new pop-up window. Select the "statistics" tab on the left. Click on "purge unused", and it will clear out all the deleted garbage. (Of course, you won't be able to "undelete" stuff earlier after doing that). If the file is still too big to post after you purge it, then sure, it's fine to upload it to Dropbox or something like that, then post the link here. As long as you use a service that doesn't spew spam when you try to download the file! - Stuart -But quickly before you go... I'm sure theirs a way to shrink my sketchup down to postable size but im new to the program. Any quick tips on how to get the file up? Is it ok for me to post the file up on sendspace or other file sharing site and post the link to the download here?
Didn't have much luck shrinking down the Sketchup file but
Here's the link to download the sketchup file for anyone that would like to take a look....
http://www.sendspace.com/file/c9bfpk
Notes about the drawing :
1. I went a bit layer crazy so I could make this drawing more accurate. The constructions in the drawing that currently exist are the slab, masonry, joists, decking, exterior walls, control room walls and ceiling trusses, and all interior walls that are on the joisted half of the building. The live area is still just a wide open space like it shows in the pictures above.
2. If you notice that the studs and such are not on exact 16" centers, its because they aren't in the existing construction.
3. Some of the pictures above show the CR windows. The window frames will be resized soon to match the window dimensions and placement in the drawing.
4. I would appreciate and encourage anyone who would like to download the drawing, make some changes or suggestions, and repost. If you do so, thanks for your time!
Hope the drawing helps to describe my scenario.
Thanks all!
So it's been a few weeks since I started this thread. It looks like about 100 people have seen it but no one's replied.
I'm trying to be patient but the suspense is killin' me folks!!
Can anyone post some thoughts or comments?
Thanks all.
Oooops! :oops: There I was saying I would get back in a couple of days, and then I went on vacations without ever bothering to reply! :oops: :oops: :oops: Sorry about that!
That's a pretty good ratio, and a nice size for the CR. ITU specs call for a minimum of 215 ft2 floor area for a two-channel control room (2.0, 2.1), and 322 ft2 min for multichannel (5.1, 7.1, etc.), so at 308 you could go either way. Are you planning 2.0 or 5.1? Also, it is generally recommended that the LR should be at least twice and preferably around five times the volume of the CR, so even if you have the same height ceiling in both, you'd be good there. And since your LR ceiling is higher, that's great!308sqft control room, 1180 sqft for live & iso space,
Layer crazy is good, in my book! You should see some of my studio designs: they can have over a hundred layers.... :shock: (I kid you not...) So as far as I'm concerned, you did great with that! Makes it MUCH easier.I'm new to sketchup and got a little layer-crazy
Right! And it's also a lot of work to try to do all at once. Are you going to do all this work yourself, or hire contractors?My plan is to tackle this mammoth in sections because different parts of the building have different needs.
That sounds reasonable.My budget for building out the interior of the studio is about $40-50K.
Oops! That's a square profile. Your length is almost exactly double your height, so all the modes related to those two axes will line up, just one octave apart (the even harmonics of height will match the odd harmonics of length, all the way up the scale). In general, you should avoid dimensions that are within 5% of being double or triple each other. So your control room fails one of the three critical tests. Fortunately that can be fixed without too much pain, as you only have framing up so far. Not a big deal to move a wall or modify the ceiling.CONTROL ROOM: L= 20' 6 1/2" W= 14' 3 3/4" H= 10' ceiling dropping down to 8' over the rear 4 feet of the room.
:shock: OOOPS! And a big one! To put it bluntly: you have built your control room on top of a very large kick drum :!: There's no easier way of saying it. That crawlspace is nothing but a large resonant cavity, and it will cause you endless problems. The floor is a resonant membrane stretched across a resonant cavity: ie. a drum. This is a major problem. Every time your speakers play a note that happens to be related to either the floor itself or the cavity under it, or both, then the note will either be enhanced or sucked dry by the resonance. Your frequency response in that room will be all over the place, and there is no way of fixing that later with acoustic treatment in the room. In essence, the entire floor IS acoustic treatment, but doing random unknown (and unwanted) things at unknown frequencies. What you have done, in effect, is to float your floor, but in the wrong way. This thread should help to guide you to the only sane conclusion, but it's a conclusion that I'm sure you don't want to get to: viewtopic.php?f=2&t=8173Current Status: The control room is on floor joists above a crawlspace with one layer of 3/4"plywood decking.
You mean a 2" gap between frames, right? Not a 2" air gap?The walls are double 2x4 walls with a 2" gap in-between.
Then there's a major design issue here! The inner-leaf of the control room must be self-supporting, and must NEVER touch the outer leaf. The inner-leaf walls can structurally support only the inner leaf ceiling, not the outer leaf. If you are relying on the inner leaf walls to support the outer-leaf roof, then you have a major structural design problem that needs correcting. However, your SketchUp model does not show any inner leaf at all! It only shows the outer-leaf, which is confusing. Or rather, it shows part of what could be an inner leaf in some places, but not in others, and even then those parts are firmly coupled, instead of being separate. In summary, there's a big problem with the concept of the framing: It is not correct structurally, and it is not correct acoustically. It is not doing either correctly.Unfortunately these walls are capped with a 2x10 due to certain structural needs of the building so they are not full decoupled from each other which totally sucks.
Personally, I would go with the BM5A's for the actual speakers, but still put the NS-10s in the room for show... without actually connecting them! :) :mrgreen: 8) )As for monitoring I will have some NS10's, mixcubes, and dynaudio BM5a's to choose from for near-fields.
Smart move! Yes, build them now completely, designed for the exact speaker you plan to install later.As the studio grows I would like to add a pair of soffit mounted loudspeakers to the control room. Probably a pair of Augspruger GA115's with a single sub. I want to construct the soffits now but leave them covered and still working as traps until we get loudspeakers.
What is your basic design concept for the room? Are you going with LEDE, RFZ, CID, MR, or something entirely different? That's the starting point.1) Acoustic Design- When dimensioning this room, I knew how much space I needed to have a comfortable, decent sounding workspace but am still uneasy about choosing the different angles in the room and the treatment methods. After a bunch of research I think I'm close to what will work but could definitely use some help.
Where? Looking, but not seeing.... :)See the design pic below.
Looks about right.On the sketchup drawing you can see that I made a rough footprint of the speaker soffits angled at 30.
:shock: "Helmoltz absorbers"? :?: Are you sure about that? Maybe you mean "slot wall"? Pure Helmholtz resonators are notoriously difficult to tune to the correct frequency that you are trying to target, and even then they need to be positioned at a point in the room where the pressure node for that mode is at its peak, or close to peak. Then they also need to be rather large to have a useful effect on the room. So I guess you are talking about using broadband slot walls there?the front helmoltz absorbers angled at 12,
To be honest, I think it would make more sense to just put Superchunks in the two rear corners, with hangers next to them, or even hangers in the corners ranging to larger and larger sizes as you get closer to the side walls.and the rear absorbers angled at 6. Notice the bass trap across the back of the room that I plan to fill with hanger traps.
You need to have a cavity that is about 1% of the room volume for each of the frequencies you plan to target. So if you plan to target ten frequencies, you'd need to use up 10% of your room volume for that.... :shock: What frequencies are you planning to target, and how are you planning to do that? Helmholtz resonators for very low frequencies are really hard to do, so you should make them tunable in some manner, such that you can adjust them as needed to hit the actual mode that you are after. This isn't easy to do, and is going to take a lot of time and care, with no guarantee of success. I would seriously consider dropping the idea of using tuned bass traps, and just go for broadband treatment, such as Superchunks and/or hangers, which will cover all your modes with no tuning required.If my calculations were correct my helmholtz's are about the size that they will need to be to help with the rooms frequency issues.
Yup. Smart move! And also keep the floor solid, hard, massive and reflective...I was also considering using clouds over the room and less absorption on the walls.
It looks to be far enough back that it won't be a problem, but the only way to tell for sure is to ray-trace.I know this window is in the RFZ which is a bad place for glass but am wondering if leaving it there would corrupt the sound in the mix position.
:lol: :shock: :!: :D Yup! If you weren't crazy, you wouldn't even be here on the forum, taking about building your own studio! :) Insanity is a key requirement in all studio builders.... So far, your biggest issue (and it IS a biggie) is that floor under your control room. That has to be fixed. Without rectifying that, your chances of having a great control room are very low. The next "biggie" is the framing. There's a conceptual issue there that needs to be fixed: The outer leaf (building shell) ONLY supports the outer leaf, and the inner leaf ONLY supports the inner leaf. There can be no mixing of the two. If you cannot support the outer leaf without resorting to connecting it to the inner leaf, then you are using undersized lumber, of the wrong type, spaced too far apart. Or you need to switch part of the structure to steel. Those are the two major issues so far. And to add another rock to the pile for beating yourself over the head... :) I would seriously consider rotating the control room 90° right, so it faces the LR. Then you can have a clear view of what is going on in there, without ending up with whiplash from cranking your neck back and forth every few seconds. To my way of thinking, sight lines are very important to the smooth flow of a tracking session: you need to be able to see the musicians and they need to be able to see you, almost as much as they need to be able to see each other.B) Am I bat-shit Crazy? … Please take me to school on this one guys! any suggestions or comments would be a big help.
If the walls are fully coupled through the ceiling and also through the resonant drum head floor, then there isn't much point talking about isolation here: there wont be much. I doubt you'd get more than 40 dB, if you are lucky. Hardly better than a typical house wall. It matters not how big you make the air gap, or how much insulation you put in, since that isn't the path that sound will take: it will take all the flanking paths through the structure of the building, totally bypassing the insulation and air.With the existing double walls of the control room being capped and coupled to each other and the floor decking (9' thick total frame) my plan was to put up another 2x4 wall from the slab to the roof trusses 6" outside the right control room wall that will be the resilient "spring" wall and barrier between the CR and Live area.
You'd be wasting your money. Green Glue is great stuff, but only useful if the wall is already well isolated. It can't do anything about flanking paths. Also, 1/2" drywall is too thin. 5/8" is what you need.With this in mind I figured I'd be fine if I constructed the inner CR walls using 4" of OC703 in-between the studs, 2 layers of 1/2" drywall glued with green glue and screwed directly to the studs, caulked and sealed accordingly.
Forget the clips and the RC. You don't need both anyway, ever: RC decouples, and clips decouple, so one or the other, but not both. And you can't even use RC with clips: it wont fit. For clips, you need hat channel, not RC. But if you have a proper decoupled two-leaf wall, then you don't need RC or clips! But you also posted photos showing that the building already exists, with siding and all, yet you are now talking about putting the outer leaf on RC: that means you'd have to take off the siding from the outside of the building, put the RC on, then re-hang the siding from the RC... I'm not even sure that code would allow you to do that. So I guess you are talking about only doing that on the other three sides of CR, not the side that faces the building outer leaf? Even so, it makes no sense to do it that way around with the mixed framing design you have right now.The outer spring/barrier wall will be constructed of 4"of OC703, 2 layers of 3/8" drywall, glued/caulked/sealed, screwed to resilient channel on clips. That will make out to be - Inner Leaf / 4"insulation / 12" air space \ 4" insulation \ Outer leaf on spring.
IT would if done properly, but not in your case, since you are not planning to decouple your walls, and you also have that resonant monster growling under the CR floor.I'm pretty sure that will stop any sound from the live area from getting into the control room if installed properly.
Simple answer, plain truth? No. Not even close. You didn't say how much isolation you want, in terms of dB, but you'd basically be limited to mass law like that, minus the flaking, minus the resonant monster: I'd hazard a guess at about 40 dB isolation, with luck. I doubt that is anywhere near enough.A) With my existing CR double walls being coupled to themselves by the 2x10 cap and coupled to the floor decking with no spring, do you think the way I intend to finish the walls will achieve my desired isolation?
Adding MLV would improve one thing only: the balance sheet of the MLV manufacturer! :) It won't to anything for your isolation that could not be accomplished much cheaper in other ways. To stop sound you need mass. MLV is very expensive mass. Drywall is very cheap mass. Which do you prefer? :) Sound waves don't care about price tags: all the react to is mass, regardless of how much it cost you to put there. So go with the least expensive mass that will do the job. MLV is only useful in a few specific cases that drywall can't handle, such as wrapping noisy pipes. Apart from that, the only benefit is to the guy who sells it. Despite the claims of some manufactures and dealers, there are no magical materials. ALL building materials obey the laws of physics, and those laws are crystal clear about how sound can be stopped and controlled. Magic and snake oil do not come into the equations at all.B) Any thoughts on working a mass loaded vinyl or audio mute material into this equation to improve it?
Actually you already DID float it, and that is the entire problem! You might not think that you floated it, but you did.... sort of. And it desperately needs to be "un-floated", brought back down to earth, so to speak: Your CR floor needs to be solid concrete, nothing more, thing less. It does NOT need to be a drum, which it is right now.3) Floors - I'm gonna keep this one short since I'm pretty sure I know the answer. The 3/4" CR decking sits on 2x10 joists 2 feet above the slab below that is a crawlspace. I'm planning on adding an 1/8" layer of MLV and another layer 1/2" ply to the existing floor before the finish flooring to add mass. I'm gonna say it…"Do I need to float my floor?" Honestly, I sure as Shit don't want to!!!
Not really, since you are greatly underestimating the power of resonance. It's a good tool that you can use to your advantage in studio design, but it is also a wild beast that can destroy things in ways you never imagined if you don't control it. And one way to unleash the beast is to give him a wonderful dungeon to roar and rumble in, right under your CR.... (I'm feeling a bit poetic today! sorry....)I figured that by building the barrier between the CR and live area the way I described it in #2 above that It would provide enough isolation between the sounds of the live room and the sounds of what is seeping through the floor into the crawlspace under CR.
Good! Then you need to "un-float" the one you already half-floated! You are totally correct that you do NOT need to float your floors! Not any of them. So you just need to undo the floating that you already did unintentionally.Questions for # 3 - A) Given the crazy added costs and weight of floating floors and in my scenario. I really don't wanna float my floors.
OK: "NO!" But that "NO" probably doesn't make you happy, since it implies something that I'm sure you don't want to do...Do I need to float my floors, and why? (please say no, please say no, please say no…)
See above for my opinion of MLV (not just mine: it's the general consensus of studio designers). Needless cost. Very expensive mass. Very few legitimate uses in acoustics. Can easily be forgotten entirely.B) Do I even need to bother adding MLV to the floor or will 2 layers of ply on some felt do the trick?
You might have to, if you don't fix your isolation! Let's say you are tracking a typical rock band. The drums are putting out around 115 dB. Your walls are stopping 40 with luck. so you have 75 of drums in the CR.... so your monitors need to be much louder than that: You'd better turn those puppies up to about 95 dB at least, if you hope to be able to hear the drums on the monitors above the drums bleeding through the walls, floor and ceiling. And even then, it won't do much for the pumping vibration under your feet, with each and every thump of the kick drum... Then there's the bass player, proudly slapping away on his beautiful six-string bass, with his amp turned up to eleven, and your chair, floor, desk and console happily rumbling and humming to the tune of the bass line, as they bounce and float around the room.... OK, so I'm exaggerating just a little, but not much. There's a major issue with resonance, and a major issue with isolation. They need to be addressed urgently, before you carry on building. Right now you are just at the framing stage, so the modifications can be done without too much pain (but still a lot of pain, nevertheless).Again, while I'm recording clients I'm not monitoring them at 100 db.
Excellent idea! But the soffits need to be designed with the specific speakers in mind: The location, angle and innards of the soffit have to fit the speaker that you plan to use. If not, then you'll have to tear down the soffit and re-build it when you buy the speakers. That said, I once did a soffit design for a guy who wants to be able to change out his speakers with unknown other speakers in the future, and it works fine. But it's far more complex than a normal soffit, since it has to account for speakers that might be taller or shorter, deeper or shallower, heavier, lighter, oriented differently, shaped differently, etc. It can be done, but it complicates things. Better to know in advance exactly what speaker you plan to use, then design the soffit (and the entire room!) around that.4) Speaker Soffits - Never done this before! Definitely need some help! As described above, as the studio grows I'd like to upgrade to a pair of soffit mounted loudspeakers. I'd like to construct the soffits framing now and just have them operating as hangar traps covered by a cloth finishing or solid piece of ply until I get loudspeakers. Once speakers are chosen I'll remove the cloth covers or cut into the ply and rework the cavity to properly house the speakers. Good idea? bad idea?
Why? Also, not sure where you got the 4' 6" figure: Standard speaker height is 3' 11-3/4" (which is 47 1/4", or 1.2 m exactly). Why do you think that won't be high enough? You'd need a very high desk or unusually tall console to make that unworkable. What is the reason in your case? If you want your room to sound good and have mixes that translate well, you really should stick to the standards as much as possible.In the end, my speakers will have to be angled down at the mix position because they will need to be more than 4' 6" from the floor.
Never, ever, ever, ever more than 10°, and the usual recommendation is not more than 7°. Personally I've never gone over 5°: Tilting your speakers adds a whole new Pandora's box full of artifacts that you really could do without: reflections off the console into your ears, comb filtering, reflections off the desk surface, phase cancellations, psycho-acoustic mirages, displacement of the stereo image from its true location, etc. Not stuff to be take lightly. It also introduces complexity into the soffit design and construction: the front faces of the soffits now become trapezoid, instead of rectangles, and you need to do fancy stuff to make those blend into the side walls, front wall and ceiling. Then you have to figure how to angle the framing at the exact identical angles on both sides, and how to anchor the speaker so it can't slide down the tilted shelf from vibration, while also NOT anchoring it since it must remain decoupled from the soffit structure... It's a big can of worms you are getting into when you tilt your speakers! Are you SURE you want to do that, on your first try? I really try to avoid it, unless there is no other option, and then I spend hours and days grinding the numbers to come up with something that works....I can't figure out exactly what angle to use for the slanting of the soffits
It's not just about distance: It's about geometry. The geometry between the speakers and the mix position, and also the geometry between the speakers and the walls. There are a lot of trade-offs involved, and a lot of fiddling to get it right. Here's the ITU specs: That's the simplified version: it's actually more complex than that, since you have to take into account other things too.Im not exactly sure of a good ballpark distance for loudspeakers to be from the mix position. I've worked in studios with great loudspeaker systems but never thought about how far away they were from the mix position. I know it probably varies from speaker to speaker and room to room.
6 feet high? :shock: That would put them up near the ceiling! Way, way past the 10° limit. You will have major reflections off the console and desk surface like that, and your soffit faces will look like mangled bat wings. The psycho-acoustics will be big-time problematic: the stereo image will be distorted and frequency-dependent: each instrument will seem to be in a slightly different place, depending on what note it is playing... That's a simple artifact of the way your ear and brain process sound coming in from above instead of from in front. There is no treatment that can fix that. I would seriously re-consider your wish to mount speakers up with the stars and asteroids....I'd like the speakers to be 6' +/- high and angled down to the mix position.
Not at all! No problem in the least. To me, long posts show dedication to detail, so that's a very big plus in your favor, as far as I'm concerned. You really want to get this place right, and you are really worried that it isn't right, or you would not have written at such great length, nor taken such great care in doing your SketchUp model. So please don't worry at all about long posts are adding too many details! On the contrary, it's the folks who post too little detail and tiny posts, who get the least help around here! I normally try to put as much effort into answering as the poster puts into posting. The guy who just posts a picture of a square and text saying "This is my room. How should I design it?" gets zero help from me, since he put zero effort into that. But you put a lot of effort into yours, so I hope I've done likewise, and managed to help you somewhat to get on the right path! But if not, then let me know what I missed, or what I didn't explain clearly, and I'll give it another shot. Also, I hope I haven't bummed you out to much with all the negative stuff about things that are wrong with your design: I kind of have this habit of just blurting it out straight, no sugar-coating, no beating around the bush. Some folks don't like that direct "in your face" response, so I hope it hasn't rained on your parade! You have a REALLY nice space there, with major possibilities for making it into an excellent studio. You have the budget to do it right, and you clearly have the desire to do it right, so all of that bodes very very well. Don't let my harsh attitude discourage you! Your place can be fantastic, but it does need some pretty big changes to get it there. The path you are on right now is not going to get you there.... - Stuart -I just scrolled up and realized how long this post is and how it spans over several discussion categories so I hope I don't get a lashing for posting this on the wrong board, and hope I didn't break too many rules.
Stuart,
Thank you for your response! Hope I didn't sour the vibe on your vacation by asking you about my post before you made it back to "reality" . :oops:
Not at all bummed! I actually think I'll sleep a little easier tonight. Your responses to my questions backed up all of the "voices in my head" in the decision making process on this build, and the "no sugar coating" is exactly the type of response that I wanted and respect. I'm a musician and an engineer. I'll be the first to admit that studio construction is over my head which is why I'm trying to reach out to others around the world that would be willing to offer guidance. Again, thanks to all who reply.. :)I hope I haven't bummed you out to much with all the negative stuff about things that are wrong with your design: I kind of have this habit of just blurting it out straight, no sugar-coating, no beating around the bush. Some folks don't like that direct "in your face" response, so I hope it hasn't rained on your parade!
That says it all!I want this studio to amaze people. "That'll do" doesn't amaze people.
I'm planning to go with a 2.0 system for nearfields, and 2.1 for loudspeakers. I currently work on the BM5a's and like'em just fine. I wanted to add some ns10's along side them for "industry standard"s for incoming engineers, and because I like them just the same! I'd like to have a loudspeaker system that is 2.1 using possibly some 1x15" tops and an 18" single sub. Being undecided on the exact is why I wanted to frame my soffits now to dimensions that could easily be fitted with speakers of that generic size when the time comes to install them.Are you planning 2.0 or 5.1?
I plan to do as much of the work myself as humanly possible. Given the jobs that may need to be done, I'll hire contractors for elements of the build that would be more cost effective and time saving. To be honest, at this point I don't exactly trust contractors to give the attention to detail that I think is needed for this application. I want to have my hands on as much of this as possible. It's just personal like that... 8) I will be hiring an HVAC contractor that I trust, and already have an electrical contractor to finish out utilities. Plumbing and electricity are roughed in. No HVAC contracted yet because I wanted to have my entire finish plan decided before taking that step.Are you going to do all this work yourself, or hire contractors?
Yes. Perhaps it would be wise to get to the nitty gritty of this post and address it with a "ground up" priority pecking order instead of bouncing from subject to subject. Your reply has really helped to hone my plan of action from the current status. The Control Room half of the building (the side of the structure that is up on joists, not on concrete) is the first completion priority to me. You confirmed the biggest fear I've had regarding the control room and the Hall/Booth. Having them up on joists over a crawl space was going to be the biggest demon and most crucial fix of them all :twisted: Standing in the currently constructed space and stomping my foot on the floor told me this loudly! It actually had such a good sub bass thump that I wanted to record a sample of it, :shot:, before realizing how much of a problem it would cause. I feared it acting as a "drum" that would not only resonate the control room but also resonate what bleed might come from the live room. Along with the floors, there's issue of walls not being true inner and outer leafs since they are capped with 2x10"s and coupled to the existing floors. I'd consider these the two mother#%&#@'s that have to be dealt with before this studio can thrive. First, the floors. In my mind there are 2 options... 1)Remove the existing floors of the CR and hall/booth and lower them down 2' onto the slab below. 2) Build and float another floor on top of the existing floor deck. On #1, I think doing this would definitely increase integrity on all fronts. The major downside is the cost of reconstruction to make it happen. On #2, Would floating a new floor system on top of the existing one that could support the entire inner leaf be a solution? Build a new decoupled room inside of the existing frame to isolate the control room from the structure around it? Working within the existing boundaries would definitely cost less and is what I'd rather do so I'm not eating the cost of the current build. But at the end of the day, it has to work. Do you think it is possible to work within to get good isolation between rooms? I guess that's a good place to start. Please reply when you have a minute. Thanks Stuart !! JasonYou mean a 2" gap between frames, right? Not a 2" air gap?
So no 5.1? Great. That's one decision out of the way. 5.1 calls for some changes to the design that are easy to do now, but hard (and expensive) to do later, so if you wont ever be doing 5.1, that simplifies things.I'm planning to go with a 2.0 system for nearfields, and 2.1 for loudspeakers.
It can be done. When the time comes to talk about soffits, I'll PM you some info on that.Being undecided on the exact is why I wanted to frame my soffits now to dimensions that could easily be fitted with speakers of that generic size when the time comes to install them.
Smart move! Unless the contractor has already done a couple of studios successfully, he'll need very close supervision all the time. So if you have to be there all the time watching and correcting, you might just as well do it yourself, or as much as you can.To be honest, at this point I don't exactly trust contractors to give the attention to detail that I think is needed for this application.
Great, but does he have studio experience too? If not, there's some stuff he'll have to do different from what he is used to doing. It's not as big a deal as a non-studio-experienced building contractor, but still important. Things like oversized ducts to reduce flow velocity, ducts lined on the inside with proper duct liner, silencer boxes on all wall penetrations, decoupling ducts from equipment with canvas or rubber sleeves, low-noise diffusers and registers, etc. HVAC implies chopping huge holes in your beautiful soundproof walls, so it's rather important to get it right!I will be hiring an HVAC contractor that I trust,
Again, does he have studio experience? There are many things he must do different, such as star-grounding for all outlets, running the electrical stuff very far from the signal stuff, only crossing at 90° (never parallel), having only one single wall penetration into each room, then internal surface-mount distribution within the room, etc. Many things will be different for him too.have an electrical contractor to finish out utilities
Right. Those are the biggies.The Control Room half of the building (the side of the structure that is up on joists, not on concrete) is the first completion priority to me. ... there's issue of walls not being true inner and outer leafs since they are capped with 2x10"s and coupled to the existing floors.
Both are options, but if it were my room I'd probably go with #1. Overall, it would be easier and cheaper, and probably a lot of the materials that you demo can be re-used in the rebuild. If you prefer #2, that's also possible, but complex and expensive. I'm not sure if you saw that link I gave you yesterday to the thread on floating floors, but here it is again. Required reading: viewtopic.php?f=2&t=8173In my mind there are 2 options... 1)Remove the existing floors of the CR and hall/booth and lower them down 2' onto the slab below. 2) Build and float another floor on top of the existing floor deck.
My guess is that it would be substantially cheaper than #2.On #1, I think doing this would definitely increase integrity on all fronts. The major downside is the cost of reconstruction to make it happen.
It is possible, yes, but a properly floated floor needs huge amounts of mass (read: "concrete"), and hefty isolation mounts, such as these: Two different types there: one is a spring, the other is rubber. They both do the same basic thing. The concept is that you lay thick insulation on your sub floor, cover it with plastic, set these gadgets in several key places, pour concrete around them up to almost flush with the top, wait for the concrete to cure, then use the gadgets to jack the entire slab up, so only the springs (or rubber bases) are supporting it. That gives you the mass and resilience you need to get the resonant frequency down low enough that it is no longer a problem. The fun comes in calculating your mass and other loads correctly, then locating the correct number of isolation jacks in the correct locations to get the floor to float... :) If you want to get into the theory and real-world lab tests of various types of floating floor, then this is the best paper I'm aware of for that: http://archive.nrc-cnrc.gc.ca/obj/irc/d ... /ir802.pdf Some of the graphs are scary, and show why this is not something to be taken on lightly. Many graphs show a REDUCTION in isolation at low frequencies for floor assemblies done with low mass or incorrect resilient materials... IN other words, getting the float wrong means that you have LESS isolation than you would have had if you would have just done nothing at all! Not a happy scenario... Check out the Mason Industries and Kinetics web sites for more info if you are interested in going this route.On #2, Would floating a new floor system on top of the existing one that could support the entire inner leaf be a solution?
I'm not so sure about that! A few cubic yards of concrete, half a dozen isolation jacks, ... :) What I would do if that were my place, is first bang my head on the wall for a few minutes, sigh deeply, then start taking it all down while trying to save as much lumber as possible to re-use. Then I'd carefully re-design the place, starting with the concrete slab as the basic floor, and work up from there. This also has the advantage of making it dead easy to fix your inner-leaf framing issues, and also giving you a lot of space for a high ceiling, excellent treatment, and more room above the ceiling for HVAC. The ducts and silencers you need for those rooms are going to be rather sizable. You didn't show the roof trusses and deck on the SketchUp model, so I'm not 100% certain, but my guess is that there was very little space up there between the CR ceiling and the roof trusses for running HVAC. Realistically, you need at least a foot, preferably two feet up there for your ducts. They have to be much larger than would be normal for a non-studio installation of the same size rooms, since the flow rate has to be kept the same, but the speed has to be lower, meaning the volume has to be higher, meaning large ducts. They also have to be lined on the inside with 1" duct liner all around, so they need to be 2" bigger in both dimensions, just to account for the lining, plus the extra size for the larger volume / lower speeds... I'm getting a bit sidetracked here: HVAC is another issue that we didn't get to yet, but it does need to be considered in the initial CR and LR design, since it just takes up so much darn space! Silencer boxes for a room that big can be huge... I did notice some consideration for HVAC on your SketchUp, but not enough.... So that would be my plan: take it down, working carefully to save as much as possible of the materials, then re-design and re-build. - Stuart -Working within the existing boundaries would definitely cost less ...
I've read this one a few times. I knew immediately that the CR floor was going to be trouble so I've been trying to explore all potential solution options of working within the existing construction.I'm not sure if you saw that link I gave you yesterday to the thread on floating floors, but here it is again. Required reading:
Agreed. As opposed to floating a concrete floor, which probably wouldn't be a smarter solution than just cutting out the existing floor and setting up flat on the slab, I was wondering if a timber "raft" on neoprene blocks on top of the existing floor with a good massive deck and insulation in the cavity be an option? I know it comes with the complexities of calculating loads amongst other things. Or would doing so just end up making another resonant "drum" on top of the existing one? I read thru the lab test pdf you attached.thanks. Pretty informative and pretty scary.If you prefer #2, that's also possible, but complex and expensive. A few cubic yards of concrete, half a dozen isolation jacks, .
BANG! BANG! BANG ! BANG ! :cen:What I would do if that were my place, is first bang my head on the wall for a few minutes
If this ended up happening, would using the slab as the floor be possible? probably not directly on the concrete, maybe some tile. Or put down a vapor barrier, thin sand cavity, and hardwood flooring on top? Or would you suggest having the concrete be the subfloor and then floating a new floor on top of it? I realize that if I had to cut out the floor and start over that I have the advantage of revamping the entire design, and reusing as much material as possible. It's funny how you said " I'd strongly recommend rotating the CR 90* ". I've been thinking the exact same thing and already made a full second design implementing that. :D I found that it makes the whole space function better. If the floor has to come out, then the redesign will be easy to construct. But before taking that massive plunge I have to eliminate all options of building within what exists first just to be thorough. :horse:Then I'd carefully re-design the place, starting with the concrete slab as the basic floor, and work up from there. This also has the advantage of making it dead easy to fix your inner-leaf framing issues, and also giving you a lot of space for a high ceiling, excellent treatment, and more room above the ceiling for HVAC.
:lol: thanks. I know its going to take a lot of blood and sweat to get this place on par, but I'm up for the challenge and that's why I'm here! Thanks again for your time and interest.You have a REALLY nice space there, with major possibilities for making it into an excellent studio.
It's another option, yes, but the key words here are "a good massive deck". As in majorly massive. Isolation in a two leaf system comes from using resonance in your favor (instead of against you, which is what you have now). The basic concept is that a two-leaf wall is a "Mass - Spring - Mass" system, and follows the equations of physics that govern such systems. If you hang a spring from something rigid, then hang a weight on the bottom of the spring and give that weight a tug, it will bob up and down on the end o the spring for a very long time: it is resonating. It will only do that at one specif frequency, which is set by the amount of mass and the "bounciness" of the spring, also called "resilience". If you try to make it bounce at another rate, either faster or slowly, it will actively resist your efforts, and as soon as you stop trying it will instantly go back to the same rate as before. It does NOT want to resonate at any other frequency. Pushing a child on a swing is another example of the same principle: it's really hard to make the child swing faster or slower than than that natural resonant frequency of that system. A two-leaf studio wall, or floor, or ceiling works on the exact same principle: the massive leaves on each side are Mass #1 and Mass #2, and the air trapped between is the spring. We don't normally think of air as being "springy", but to a sound wave it sure is! So the wall/floor/ceiling is also a Mass-Spring-Mass ("MSM") system, and just like the weight bouncing up and down, it also wants to resonate at one single frequency, and "fights back" against all other frequencies. At its resonant frequency it does not isolate at all, and in fact it amplifies the sound, making it louder. But at all other frequencies, it isolates. So if you can set the conditions right so that its natural resonant frequency is outside of the audio spectrum, then bingo! It isolates ALL frequencies that you can hear! Simple! so how do you "tune" the wall to get it to resonate at the correct frequency? There are only two factors in the MSM resonance equations for walls and floors: the mass on each leaf, and the resilience of the spring. For a wall, the spring is the air between the two leaves. For a floor, it is the steel springs or rubber pads (and also the air, to a certain extent). As you increase the mass on both leaves, the resonant frequency goes down. As you increase the size of the air gap (or the resilience of the spring/rubber), the resonant frequency goes down too. So with a bigger gap or more mass, you get a lower frequency. In reality, the system amplifies at resonance, is neutral at 1.414 times resonance (neither amplifying nor isolating), and isolates above that. So you need to get the resonant frequency down to about half of the lowest frequency that you want to isolate. In other words, if you want to isolate down to 50 Hz, you need to get resonance below 25 Hz. If you want to isolate down to 20 Hz, you need to get resonance below 10 Hz. Etc. Of course, Murphy steps in here: the lower you go, the harder it is to go further... There's a "square root" operator in the equation, so the effect is exponential. Don't you just love acoustics? Just when you think you see light at the end of the tunnel, it turns out to be the headlight of an express train coming at you... If you are interested, the equation for MSM using air as the spring is this: That's the full equation: it can be simplified by making some assumptions and combining the fixed values into a single constant: F = 60 * [(m1 + m2)/(m1 * m2 * d)]^.5 Where m1 and m2 are the two masses (surface density, in kg/m2), and d is the distance between them (in meters). The constant of 60 is for an empty cavity, but if you fill the cavity with suitable insulation, then you can change that to 43. Insulation acts as a damper, like putting a shock absorber inside your car suspension springs. It damps the resonance, which further reduces the resonant frequency and greatly improves isolation. If one of the masses is extremely large with respect to the other (eg, you have a 10 inch reinforced concrete wall as the outer leaf, but only a single sheet of 5/8" drywall for the inner leaf), then you can simplify the equation even further: F = 60 / [(m * d)]^.5] Where m is the mass of the drywall, and d is the size of the air gap. OK, that's for using air as the spring. If you use a physical spring, then the equations are a bit more complex, since you have to take into account the resilient properties of the rubber or spring, which are likely non-linear, but the same basic principles apply. But no you only have one variable: you cannot change the resilience of the rubber (unless you rip it out and put in another type of rubber), so your sole remaining method for tuning the floor to the resonant frequency that you want, is mass. The lower mass in your two-leaf MSM floor is the concrete slab on grade, and that is extremely massive: you have the entire planet down there! That's hard to adjust. So you are left with only the other mass, on the top leaf. That's all you can change. OK, so far so good. so you get some rubber pucks, and you put some mass on them, and bingo! Resonant system! Floated floor! Weeellll..... not so fast. There's the issue that rubber is not compressible, like air is, so it acts a bit different. Rubber doesn't compress when you load it: it squishes down and spreads out. The amount of "squish down" is called "deflection", and that's the key to making your floor float. Air is a spring all the time, compressed or uncompressed, but rubber has to be loaded to the right deflection or it wont "spring". If you put too much load on it, then it "bottoms out" and is no longer resilient: your floor won't float. And also if you don't put enough mass on it, then it "tops out" and is not resilient: your floor won't float. So you have to get just the right amount of deflection in the rubber to get it to its optimum loading for peak resilience. With air, it doesn't matter: it is always "bouncy", so you just set the right size gap for the frequency you want, but with rubber you also have to get the deflection just right so the rubber is bouncy at all! Get it wrong, and there's no bounce. And you wasted an awful lot of time, money and effort, all for nothing. With air, it doesn't matter if you accidentally put too much mass on a leaf, and in fact that's a god thing! But with rubber, putting too much mass on by accident will totally kill your isolation. All that to say that floating a floor is a complicated issue: getting just the right load to get the rubber to optimum deflection and resilience is a big deal. Lots of calculations involved. And then there's the additional issue of the variable load on the floor! It will be much heavier in some places (eg, where the desk and console are, or where the sofa is), and much lighter in other places, where there is just bare floor: so you need to take that into account by have a larger area of rubber at the heavily loaded locations to keep them floating, and smaller pads at lightly loaded places. But then there's the issue of variable loading: what happens when a musician drags in his huge 400 pound speaker and amp stack, and leaves that sitting on the floor? Or what happens when you have four "well built ( :!: :shock: )" folks sitting on the sofa, as compared to nobody at all? What will that extra thousand pound load do to the rubber under the sofa? Does it overload it into bottoming out? How do you account for that? Etc. Designing a floating floor system is fun and games! The only real way of dealing with all those variables is to make the floor so massive that none of them make any real difference, and make it so rigid that the load is spread evenly, regardless of where you place it. I think you see where this is going: you cannot do that with just wood. Wood is flexible and low mass. But concrete is rigid and high mass. To put numbers on it, the density of plywood comes in at around 500 kg/m3, so a deck of 3/4" plywood weighs about 10 kg/m2. For concrete, the density is about 2300 kg/m3, so a 4" slab weighs about 230 kg/m2. Just a slight difference! To get the same mass with wood, you'd need twenty three layers of 3/4" plywood. Now I'm not sure how much wood costs in your area, but I'm betting that a 4" concrete slab is going to work out somewhat cheaper than 23 layers of plywood! :) Not to mention that 23 layers of 3/4" plywood is over seventeen inches thick... OK, that's my long and rather convoluted way of answering your question: "I was wondering if a timber "raft" on neoprene blocks on top of the existing floor with a good massive deck and insulation in the cavity be an option?" Simple answer: no, using a wood deck is not a feasible method of floating your floor, despite what some manufacturers of rubber pucks want you to believe! The amount of mass you need to solve the variability issue just makes it totally impractical, even assuming you could figure out the math. In theory their products will work, but in practice.... Not so easy to do! If you take a look on YouTube, you'll see numerous videos of people happily and proudly showing how they are floating their 1/2" OSB floors 2x4s and rubber pucks. But strangely enough, they never seem to post a video about the final outcome, nor show actual objective test measurements of the isolation they achieved with their "floated" floors .... I wonder why? :)I was wondering if a timber "raft" on neoprene blocks on top of the existing floor with a good massive deck and insulation in the cavity be an option?
Yup!know it comes with the complexities of calculating loads amongst other things.
Exactly. Scary is the word. Do it wrong, and you can easily end up with 10 dB WORSE isolation than having no floor at all! That's what I call scary...I read thru the lab test pdf you attached.thanks. Pretty informative and pretty scary.
Yup! In fact, there really is no better floor for a studio than plain old concrete. Surprising, but true. If you look over some of the threads here of people who have already completed their studios, you'll see some really cool examples of what can be accomplished with concrete: it can be polished, buffed, stained, lined, etched and treated in other ways to look fantastic, and it makes an excellent acoustic surface. However, some people just don't like the look of concrete, or maybe your concrete is in bad shape to start with, so there are other options. One of those, as you suggested, is ceramic tiles. They can look really nice too, and also provide a great acoustic floor. Another option, which is cheaper and easier to install than tile, is laminate flooring: It goes in fast, and looks fantastic, and is also really good acoustically. Linoleum is another option. Anything that is solid, hard, and reflective is good. The wall framing goes directly on the concrete, of course, then the floor is laid right at the end, after the room is practically finished.If this ended up happening, would using the slab as the floor be possible?
I'm not too knowledgeable about hardwood flooring, but I understand that it cannot be laid directly on concrete: it needs a sub floor with an air gap, and that is a Big Bad Thing, of course. Any flooring that requires air under it is a no-no for studios. Flexible underlay is fine (such as the thin underlay that goes under laminate flooring), but nothing with entrained air.and hardwood flooring on top?
Not worth the money or effort, unless you need extreme isolation. That's a good point, actually: How much isolation do you need, in terms of decibels? Both between rooms and also from each room to the outside world. Those are key numbers! Your entire design should be based around those numbers, so it's important to get them right.Or would you suggest having the concrete be the subfloor and then floating a new floor on top of it?
:thu:I realize that if I had to cut out the floor and start over that I have the advantage of revamping the entire design, and reusing as much material as possible.
Exactly!It's funny how you said " I'd strongly recommend rotating the CR 90* ". I've been thinking the exact same thing and already made a full second design implementing that. :D I found that it makes the whole space function better. If the floor has to come out, then the redesign will be easy to construct.
Not only is that horse thoroughly dead, it is no beaten to a mushy pulp, I think! :) Decision time.... - Stuart -have to eliminate all options of building within what exists first just to be thorough.
Stuart,
After thinking on it constantly for days now, the horse has come back as a ZOMBIE horse!
I have a few more theories to bounce off of you before this subject has been thoroughly beaten and shot. In the head. With a silver bullet. :horse:
I appreciate you taking the time to reply as you have been so I hope I don't get on your shit list for bringing this back up. I swear I'll change the subject soon. lol
To quickly recap on the floor conversation... the layers of my existing floor surfaces from the ground up are...
EARTH
1.Concrete Slab
2. 2' crawlspace
3. 2x10" joist system sitting on cinder block walls
4. 3/4" ply floor decking.
CONTROL ROOM
The main threat discussed in this thread so far is that having my floor above this 2' space will cause the dreaded "drum" effect. Bad. Most obvious solutions - 1) demo the floors and setup on the concrete, 2) make the existing deck much more massive and build a new floated system inside.
OK... We both know solution 1 is the best solution. But, just for now, lets say it wasn't an option. Lets say there was a basement below or this CR was on the 2nd floor of a structure where the area below wasn't occupied so it could be modified or disturbed, but not deleted. If that were the case how would you handle it if you were stuck with it and had no other option?
This is what I was thinking......
First, I would go into the crawlspace underneath and reinforce the floors with 4x4" beams on jacks (like i did in my existing home studio) adequately spaced to take the "bounce" out of the existing joist system that currently "half-floats" on the cinder block walls, and to make it more rigid and able to support more mass above. Then fill all the cavities in between the 2x10's with thick insulation bats.
Second, I would pour a 1/4"-1/2" of self leveling concrete on top of the existing 3/4" decking adding about (2 lbs per sqft @1/4" thick x 300 sqft = ) 600-1200 pounds of mass to the floor depending on the thickness I end up going with.
Third, I would finish the floor with a porcelain or stone tile. Tile ranges from 4-8 lb/sqft depending on the item used so that would be (4 lb x 300sqft = ) 1200 lbs. If I did the light side of this arrangement it would add almost a TON to the mass of my floor. After all that, I'd like to think its safe to call that floor massive and rigid.
The final step would be going back into the crawlspace and filling the 2' air space between the bottom of the joists and the concrete slab with insulation to dampen whats left of the "drum" effect. I've heard of people in similar situations that just bought rolls of R-13 or higher insulation, cut the sides off of the wrap to expose the insulation, and fill the entire crawlspace with the still intact rolls instead of actually opening the rolls and laying it out in sheets. The major issue is the drum issue caused by the air space but we all know what happens when you stuff a blanket in a kick drum. it doesn't terminate the sound, of course, but greatly decreases its ability to resonate.
I know the theory I described above won't totally solve the problem like dropping the whole thing down to the slab, but I like to think it would get the problem down to a not-so-awful, tolerable level.
Could you please give me your opinion on this theory?
If you think it's a totally bunk idea, what would you do to fix things the best you could if you had no other choice but to proceed without removing the floor joisting system?
Again, I really appreciate you beating me over the head with a bag of bricks and helping me come to a decision.
" Thank you Sir, may I have another!!!" :horse:
To add to my previous post...
What about adding drywall to the underside of the 2x10s making the floor be from bottom to top-
Concrete / 2' crawl / drywall-sealed / 2x10 cavities filled with bats / floor ply / 1/4-1/2" concrete / tile-mortar-grout / CR ?
Would this have a positive, negative, or no effect on the situation?
Also, in the above post when I was describing filling the 2' crawl cavity with insulation, I was trying to think of ways to eliminate or minimize the cavity below instead of occupying it.
Stupid thought?
Thanks
Jc
I think I'm gonna be haunted by the ghost of a mangled zombie horse for the next few days! :)
Can we also do a wooden stake to the heart? Just in case?before this subject has been thoroughly beaten and shot. In the head. With a silver bullet.
Yup! Which would also allow you to rotate the CR orientation for better sigh lines and acoustics, and also to fix your coupled framing problems.... Just sayin'...Most obvious solutions - 1) demo the floors and setup on the concrete,
Also possible, but does NOT allow you to rotate the CR orientation for better sigh lines and acoustics, or to fix your coupled framing problems.... You'd still be stuck with those issues.2) make the existing deck much more massive and build a new floated system inside.
If that were the case, then the recommendation would be to NOT build the CR in that location, but rather to find a slab on grade some place to do it. People do occasionally come to the forum with problems like that, and discover that building a CR on a wood-framed floor is a problem. Either they have to invest in beefing up the floor structure greatly, or they have to accept that they won't be getting much isolation.Lets say there was a basement below or this CR was on the 2nd floor of a structure where the area below wasn't occupied so it could be modified or disturbed, but not deleted.
Depends on how big the budget is! If money is no problem, then I'd go ahead and beef up the structure sufficiently to float the floor correctly.If that were the case how would you handle it if you were stuck with it and had no other option?
This might seem like an insulting comment, but it's intended to be constructive criticism: That sounds really complex and expensive. How exactly would that be easier, faster, or cheaper then taking out a few dozen bits of wood and putting the back in again differently? I mean, what you propose might work, but there's the issue o cost, complexity, and the rather important "YBYOGP" factor. YBYOGO stands for "You'd Be Your Own Guinea Pig". Since the structure you mention is not described in any of the literature that I'm aware of, you'd become your very own test lab, doing tests that nobody else ever did before....First, I would go into the crawlspace underneath and reinforce the floors with 4x4" beams on jacks ... Then fill all the cavities in between the 2x10's with thick insulation bats ... I would pour a 1/4"-1/2" of self leveling concrete on top of the existing 3/4" decking ... I would finish the floor with a porcelain or stone tile. ... The final step would be going back into the crawlspace and filling the 2' air space between the bottom of the joists and the concrete slab with insulation to dampen whats left of the "drum" effect....
Or re-orienting the CR, or fixing the framing issues.... :)I know the theory I described above won't totally solve the problem like dropping the whole thing down to the slab,
OK, I'll answer that question with another question: Why can you not proceed with removing the floor joist system? What dreadful thing will happen if you do that?If you think it's a totally bunk idea, what would you do to fix things the best you could if you had no other choice but to proceed without removing the floor joisting system?
Can I add some chunks of broken concrete, some lead shot, and a few steel balls, into the bag? :) OK, bottom line: Your plan is feasible and just might work, but you won't know for sure until you are finished. If it doesn't work, then you are very much "up the creek without a paddle". Is it worth running the risk of finding out that it doesn't work, after spending all that time and money? Tough decision to make! - Stuart -Again, I really appreciate you beating me over the head with a bag of bricks and helping me come to a decision.
Thanks again for a speedy reply. You're awesome!
Ok. Horse has been beaten, killed, buried, dug back up, shot with silver bullets, wood stake thru the heart, crucified, burned at the stake, and buried again. Done. DONE! :twisted:
You're gonna hate me and think I'm an idiot. I know I didn't describe the construction enough for you to understand why removing the floors is a bit bigger deal than you may think it is, in this particular case. I could go into why and everything that would involved in fixing it. After weighing it out, I've decided that I have to move forward with the existing floors and the theory that I have.
Damn! I heard you say "Aww man, what the f@&$?!" All the way over here in the states! :oops:
It's just what I have to do to meet my budget and deadline. I absolutely accept all blame and responsibility for what might happen by doing so and you are absolutely allowed to call me "dumbshit"
from here on out if it makes it easier to respond to me. All of the advice you've given me has been invaluable and 1050% respected and appreciated. I can't thank you enough for that and I hope you don't take it personally that I'm going against one of your rules of thumb. But when you've already given yourself lemons, you gotta make lemonade!
I know of several studios here in Atlanta that have great studios with similar flooring scenarios that are making killer recordings and don't have crazy isolation issues. I've been making great tracks in my current studio and my isolation is horrible! I know I majorly screwed up, but this build will still be light years ahead of my current setup. Luckily, the live half of the building is still a blank canvas, and none of the inner framework of the CR is up yet so maybe measures can be taken there to compensate for the short-comings of the control side. (I hear you still sighing)
Keep in mind that I'm not a pro like you are and this is my first time building a studio. I've been kicking myself since day 1 for not doing more research before breaking ground, but now I bask in my ignorance and have to deal with the hand I dealt myself. I hope you're still willing to lend your ninja knowledge through the rest of my build.
I'm preparing my next post and refining drawings to address the next phase, walls.
Any guidance you'd be willing to give would be great.
Thanks again for everything and trying to tolerate my stupidity.
-Dumbshit
Stuart,
Here's an update on what has happened in the build over the past month.
I've reinforced the control room floor with 4x4s and jacks getting rid of the bounce and have managed to separate the wall frames in the CR by splitting the 2x10 cap that was coupling the inner and outer frames together. :yahoo:
Now that the inner and outer frames are self supporting I have to design and construct an inner ceiling frame for the CR. That will leave the floor decking as the only point that the inner and outer walls touch, which i cant really do anything about. I plan to do the control room floor with 1" concrete board, possibly use a thin layer of self-leveling concrete to seal it all up, and finish with a ceramic or stone tile . I know its not as good as starting over from scratch, but its a step in the right direction. Also, I've hired my HVAC contractor who has done two nice studios in town and knows all the ins and outs which is a big relief. The rough-in begins tomorrow!
Before doing anything else, I want to lock in my CR design and the main thing keeping me from doing so is figuring out the soffits. I've seen many different designs and methods and dont know which one I should go with. I've studied the Sayers' soffit style and a few others. One in particular was the soffit at ClearTrack Studios designed by Wes Lachot. You can see it in a video here..http://youtu.be/oVnVpS5dM-E
He incorporated the soffit into the wall design and drywalled the front of the soffits and then went back and did what looked like a layer of OSB and MDF. Unlike in the Sayers style where I believe the drywall layers are on the inner wall studs and the soffits are constructed within the leaf from OSB and MDF. Is that correct? In the Lachot design, no ports or bass traps are used because the soffit is actually part of the leaf and can't be penetrated. It looks like just the boxes that house the speakers we're built and they seat in the frame and extend back into the insulated air cavity that is between the inner and outer wall frames. In the Sayers' design, the extra space above and below the speaker can be used for trapping. I'm sure each style has its pro's, cons, and specific to the scenario but I don't know what they are. I know the main attribute of a soffit is to be rigid and sturdy.
Personally, I like the Lachot design because the soffit frame is a part of the wall frame and having the drywall on the fronts seems like it would make it a very massive surface compared to just using OSB. But the speakers being in the air cavity between leaves makes me uneasy. It feels like there should be another layer behind them to contain any backward resonance from hitting the next leaf, but isn't that the whole point of "front-loading" the speakers anyway? So that all sound is pushed forward, instead of 360 degree resonance? Please correct me if I'm wrong.
I guess my question is should I design my soffits to be a part of the leaf or inside of the leaf?
I've also been considering not soffit mounting any monitors since I always work on nearfields. But of course, you gotta crank it once and a while! :twisted:
I've had my eye on Barefoot monitors for a while now, which cant be soffit mounted due to their 360 design. Lets say I we're to use such a configuration. How would be best to handle the walls where the soffits would've been? I want to keep the 30 degree angles of the walls but should I make the surfaces absorptive, maybe broadband or targeted slots, or reflective?
Trying to keep it short although I have a million questions.
Thanks for any input and hope you are well!
Jason
Hi again Jason. Glad to see you are still moving forwards!
That's probably about as good as you can hope for, given the limitations of the structure. Make that self leveling cement as thick as possible, within reason, and as thick as your structural engineer will allow!I plan to do the control room floor with 1" concrete board, possibly use a thin layer of self-leveling concrete to seal it all up, and finish with a ceramic or stone tile
Great! hopefully he'll be able to do it right, with decent silencer box design, slow speed, and high volume.Also, I've hired my HVAC contractor who has done two nice studios in town and knows all the ins and outs which is a big relief.
The basic concept is simple: You need a very solid, rigid heavy, massive structure that cannot be moved easily by the speaker vibrations, and you need a very solid, rigid massive baffle (front panel) that also cannot be moved by vibrations. The main difference in the methods of how to actually build it, is based around weather or not those two "very solid, rigid massive" things are tied together, or kept separate. Both approaches work.I've seen many different designs and methods and dont know which one I should go with.
Yeah, I've seen plenty of photos and videos of that place floating around the internet. Nice looking place, isn't it?One in particular was the soffit at ClearTrack Studios
Yup. And probably plenty of other stuff that you can't see! :)He incorporated the soffit into the wall design and drywalled the front of the soffits and then went back and did what looked like a layer of OSB and MDF.
It's the same concept, if you look closely... :) There's no difference.Unlike in the Sayers style where I believe the drywall layers are on the inner wall studs and the soffits are constructed within the leaf from OSB and MDF
It might look that way, but I'm betting that some place in there is plenty of ventilation for those speakers! They need cooling.... :) What you see in John's soffit designs are NOT acoustic ports: they are ventilation ports, that allow the cooling air to flow up behind the back of the speaker, then return to the room. If you don't want to see those ventilation ports, then there's no problem hiding them inside the soffit some place, provided that you also include suitable silencer boxes if the HVAC ducting from the speakers then goes straight out of the room.In the Lachot design, no ports or bass traps are used because the soffit is actually part of the leaf and can't be penetrated.
Once again, it's the same concept as with John's design: there is a massive box around the speaker itself that holds it rigidly in place. With both designs the speaker itself is NOT in the air gap between the leaves: that would be silly. The only difference I can see is that with John's design the speaker box is vented with the soffit back to the room, whereas with the other design the box is vented in some other way that cannot be seen, and that does not come back into the room. If you have the budget to do the extra complexity for that ventilation, then by all means go for it! The end result won't be any different. Or use passive speakers that run very cool and do not need cooling, even when run for long periods of time at high power. However, you did say you were planning on using BM5A's, which are active, have huge heat sinks on the rear that get hot, and can't be soffit mounted anyway! Or at least they cannot be soffit-mounted not easily, and certainly not the way seen in that video: You have rear-firing bass extension ports on those....It looks like just the boxes that house the speakers we're built and they seat in the frame and extend back into the insulated air cavity that is between the inner and outer wall frames.
John normally only uses the space below for trapping. The space around and above the speaker is filled with insulation, to damp cavity resonance. But there's an awful lot if useful real-estate under a soffited speaker, and it seems such a shame to just waste that, when it could be put to good use for trapping....In the Sayers' design, the extra space above and below the speaker can be used for trapping.
It is with John's design too. Especially so if you build the front wall inside-out, as John normally does.Personally, I like the Lachot design because the soffit frame is a part of the wall frame
Why? Drywall weighs about 650 kg/m3, give or take (depending on manufacturer, style, etc). OSB weighs about 600 kg/m3, and some types as much as 640 kg/m3. So there's not much in it. OSB is also more rigid than drywall...the drywall on the fronts seems like it would make it a very massive surface compared to just using OSB
The speakers are NOT in the air cavity! Take a close look at the video again, around 1:35 to 1:48: There are several views that clearly show the box that will later contain the speakers. I'm betting those boxes are massively constructed, with rigid framing around them.But the speakers being in the air cavity between leaves makes me uneasy.
Well, yes, I do have to agree with you there: if the box does resonate for any reason with that design, then that resonance will indeed be inside the wall cavity, which is not a good place for it.... On the other hand, with John's design, that cannot happen...It feels like there should be another layer behind them to contain any backward resonance from hitting the next leaf,
Well.... sort of! The issue is correction of power imbalance. With any free-standing speaker, the high frequencies are projected straight forwards, like rays of light, while the lows wrap around behind the cabinet and spread out in all directions, like a balloon. So the highs will be 6 dB louder than the lows, since the highs are going out into "half space" (the hemisphere in front of the speaker), while the lows are going out into the full sphere ("full space") all around. so if you pump the exact same power into all frequencies, then the lows would sound 6 dB quieter. The frequency where the change from "half space radiation" to "full space radiation" occurs is know as the Baffle Step Frequency, and is set by the width of the front panel of the speaker itself. If you then extend that front panel infinitely in all directions, then all frequencies are no forced into half-space, and there is no longer any power imbalance. That's what a soffit does: it forces all frequencies to radiate into half-space. Except, of course, with a rear-ported speaker. With rear ported or side ported speakers, things are different since a lot of the low energy is also coming out that port, and being lost inside the soffit....isn't that the whole point of "front-loading" the speakers anyway? So that all sound is pushed forward, instead of 360 degree resonance?
In BOTH cases they are part of the leaf! :) Technically, the soffit removes the speaker from the room and thus also removes all the associated artifacts, since the speaker is flush with the inner-leaf of the room. What you are talking about is different CONSTRUCTION techniques, not different acoustics. Both techniques, (and the Barefoot technique as well...) accomplish the same thing, acoustically: remove the speaker from the room, and hold it rigidly in the wall.I guess my question is should I design my soffits to be a part of the leaf or inside of the leaf?
:shock: If you don't soffit-mount, then you re-introduce all those nasties that soffits eliminate, such as SBIR, comb filtering, other forms of phasing issues, reflections off the walls behind the speakers, modal coupling, etc., etc,. etc. ... There's a reason why studio designers flush-mount their speakers in world-class rooms, and that is to ensure that they sound as best they possibly can, the way the designer intended, with as little distortion as possible coming from interactions with the room boundaries.I've also been considering not soffit mounting any monitors since I always work on nearfields.
BM5A's suffer from the same issue: they are rear-ported.I've had my eye on Barefoot monitors for a while now, which cant be soffit mounted due to their 360 design.
If you don't soffit mount, then the second-best is to move the speakers far enough away from the walls that SBIR is no longer an issue, which means that they need to be at least 1.5 meters away from all walls, and preferably 2 or more meters away. I'm not sure that your room is big enough to be able to do that. The THIRD best thing, is to make the room rectangular and push the speakers right up against the front wall, where SBIR will be forced up the scale to frequencies that aren't so objectionable.Lets say I we're to use such a configuration. How would be best to handle the walls where the soffits would've been? I want to keep the 30 degree angles of the walls but should I make the surfaces absorptive, maybe broadband or targeted slots, or reflective?
Questions are fine! That's what this forum is all about!!! :) - Stuart -Trying to keep it short although I have a million questions.
Hey Stuart!
Hope things are well, and Thank You for responding! :D
The jacks and spacing I used can support a metric shit-ton of weight. All in all, whatever floor finish I end up going with will be the equivalent mass of a 2" thick concrete slab.That's probably about as good as you can hope for, given the limitations of the structure. Make that self leveling cement as thick as possible, within reason, and as thick as your structural engineer will allow!
The HVAC has been "roughed-in" and ready to pass the initial framing inspection before we start doing the finishing aspect of it, i.e. the silencer boxes, and how the hvac will actually penetrate the inner leaf once their inner framing is completed.Great! hopefully he'll be able to do it right, with decent silencer box design, slow speed, and high volume.
If I saw it correctly, later in the video it shows that those that the cavities that I described between the CR and LR were used for closets to house cabling or gear between rooms?It might look that way, but I'm betting that some place in there is plenty of ventilation for those speakers! They need cooling....
Sorry, That's what I meant. Of course they will have to vent and breathe somewhere.John's soffit designs are NOT acoustic ports: they are ventilation ports
Agreed. Suspicion confirmed! 8)With both designs the speaker itself is NOT in the air gap between the leaves: that would be silly.
I do not plan to soffit mount any of my near field monitors. My BM5a's and NS-10's will be on the desk area. The soffit walls would be for housing a loudspeaker around the size of an Augsurger GA 115. I guess my question was should I build the inner leaf (framing/drywall/etc) and then construct the soffits within it?However, you did say you were planning on using BM5A's
I understand building a wall inside-out, but if I we're to construct the front wall inside-out to make for easier framing of the soffits, how would I construct the other walls? Can you construct the front wall inside-out and construct the other walls inside-in, or would you construct all walls of the CR inside-out?It is with John's design too. Especially so if you build the front wall inside-out, as John normally does.
Exactly! :DThe speakers are NOT in the air cavity! Take a close look at the video again, around 1:35 to 1:48: There are several views that clearly show the box that will later contain the speakers. I'm betting those boxes are massively constructed, with rigid framing around them.
So I guess what your saying is I kinda answered my own question. :|In BOTH cases they are part of the leaf!
You must be thinking of a different Barefoot. This is the Barefoot I'm speaking of... http://www.barefootsound.com/micromain27gen2.html When I said 360 design, I meant that there are speakers on 3 sides of the cabinet, the front for the mids and highs, the sides for the lows. Soffit mounting isn't possible. On Another Topic: I'm planning to do my LR iso booths with wood framing on a concrete floor. Whats the proper way to connect the inner framing of an iso booth to a concrete floor? Bolt the 2x4 plates to the concrete floor with a caulked seal? Use a membrane or "spring"(neoprene/expansion joint material) between the concrete and the 2x4 plate to decouple? ....Planning ahead... Thanks for any advice. I'll post updated pics and .skp soon JasonI've had my eye on Barefoot monitors for a while now, which cant be soffit mounted due to their 360 design. BM5A's suffer from the same issue: they are rear-ported.
Hi Jason
Generally (I believe) It shouldn't be necessary to decouple the wood framing from a concrete floor
…you can still place some rubber under your walls to compensate for level irregularities if necessary…
In that case:
- Get a large piece of neoprene (or a yoga mat for a low budget alternative) and cut sections the width of the base plate and place them under the base plate
- drill a hole thru the stud and then (with a masonry bit) drill into the concrete floor
- drop an anchor bolt into the hole
- put a piece of neoprene tubing into the hole and around the bolt in order to prevent vibrations from transfering from the bolt to the stud
- add a neoprene washer and then a metal washer
Here are a few pics I got around the Forum, where I found these info too…. Just echoing the experts' advice and hopefully save them some time :-)
Three caulk passes (one in the middle and two on each side of the base plate) would be a good thing to do if you can :-)
Hope this helps
Fantastic build by the way…looking forward to see it all coming together
Simo
What Simo suggests is a good idea, but it should be done with care, using the right products for the job. You can either do all the math yourself to ensure that you get it right, or you can buy something like the IsoSill products, where they already did that for you.
All the same, you should still get a structural engineer involved: he's the only guy who can say for sure if what you are doing is structurally sound or not.The jacks and spacing I used can support .... of weight. All in all, whatever floor finish I end up going with will be the equivalent mass of a 2" thick concrete slab.
I didn't notice that, but I also didn't look for it.If I saw it correctly, later in the video it shows that those that the cavities that I described between the CR and LR were used for closets to house cabling or gear between rooms?
To my way of thinking, that's the best (not to mention easiest! way of doing it.I guess my question was should I build the inner leaf (framing/drywall/etc) and then construct the soffits within it?
You can do it either way. Yes, it is possible to do the side walls traditionally and the front walls inside-out. No problem. You can also do the walls traditionally and the ceiling inside-out, or vice-versa. You just need to pay more attention to how you do the framing where the two meet, but as long as that is done right, then there's no problem with "mix and match" for studio walls.Can you construct the front wall inside-out and construct the other walls inside-in, or would you construct all walls of the CR inside-out?
:thu:So I guess what your saying is I kinda answered my own question.
No, it's the same Barefoot. There's only one of Thomas as far as I know! :) I don't think this planet could handle more than one.... The issue is that you can only successfully soffit-mount ANY speaker if it ONLY radiates energy forwards, from the front baffle. ANY speaker that also radiates energy in other directions, either with additional drivers, or with ports, or anything else that does not radiate forwards, is not really a candidate for soffit mounting. That's the point I was trying to make.You must be thinking of a different Barefoot. ... When I said 360 design, I meant that there are speakers on 3 sides of the cabinet, the front for the mids and highs, the sides for the lows. Soffit mounting isn't possible
You can do it the way Simo suggested, and you would do that for either of two reasons: 1) if you want to try to "float" your walls acoustically, so they transmit less vibration into your floor (and the other way too: floor to wall), and 2) If your concrete floor is in a bad state, ie., it is cracked, uneven, bumpy, flaky, etc., and you want to get a really good seal between the wall and the floor. If you go the first route, then you have some math ahead of you to ensure that your wall really does float properly. But if you don't need either of these two approaches, then the best method is to just bolt the sole plate to the concrete, with a good seal. That "good seal" can be achieved with acoustic caulk: before you put the sole plate down, run a bead of caulk down the full length of that sole plate, along the center line, then another bead about an inch each side of that. Set it in place and bolt it down, then fill any any remaining gaps that you can see under it, with more caulk. The caulk under the edge or each layer of drywall, as it goes up: place thin shim under the drywall to space it off the floor while you nail it in place, then pull the shim and caulk the gap. This method gives you multiple independent seals, which is A Really Good Thing! Seals are your best friend, in acoustic isolation. - Stuart -I'm planning to do my LR iso booths with wood framing on a concrete floor. Whats the proper way to connect the inner framing of an iso booth to a concrete floor?
Hey Stuart,
Hope your holiday season has treated you nicely!
I'm still a bit hung up on designing my soffit for the CR.
I'm going for RFZ and an attractive design that eats up as little square footage as possible.What is your basic design concept for the room? Are you going with LEDE, RFZ, CID, MR, or something entirely different? That's the starting point.
I got that number (which may not be exact) from this page on John's site http://johnlsayers.com/Recmanual/Titles/Acoustics3.htm The monitors I would soffit mount would be above the 1.2meter/4foot height(from center of cone, not bottom of cabinet). My small nearfields (i.e. dynaudios,ns10s) would be at this height, so I wanted my bigger soffit mounted loudspeakers to be over the top and clearing the nearfields and angled down to the mix position. Would you know off hand know the angle that is used in John's drawing linked above? Or better yet, how to pinpoint the proper angle. I'm sure it all has to do with distance from the mix position. I agree with what you previously said .... [quoteNever, ever, ever, ever more than 10°, and the usual recommendation is not more than 7°. Personally I've never gone over 5°: ][/quote] Is there an equation for this ? speaker height / distance from mix positon, etc? If you have any previous drawings of angled soffit mounted speakers that I could study they'd be a huge help! I'm also curious about how to handle the ceiling above the mix position. I've seen in other designs where the ceiling slopes gradually upward from the front wall towards the mix position at around 7-12 degrees to its highest point, and then the angle either transitions to the typical 90(square) or to another gradual upward slope to the back wall of the CR. Thoughts on this??? thanks Stuart, and Thanks to Simo for chiming in! Jason....In the end, my speakers will have to be angled down at the mix position because they will need to be more than 4' 6" from the floor....... -Stu says-Why? Also, not sure where you got the 4' 6" figure: Standard speaker height is 3' 11-3/4" (which is 47 1/4", or 1.2 m exactly). Why do you think that won't be high enough? You'd need a very high desk or unusually tall console to make that unworkable. What is the reason in your case? If you want your room to sound good and have mixes that translate well, you really should stick to the standards as much as possible.
On the "Speakers" tab? The number I see there is 1.2m, which is 47-1/4" (3'11-1/4"). Or maybe I'm looking in the wrong place? But anyway, "standard" speaker height is 1.2m. Or at least, that's the way it is defined in the ITU, EBU and AES specs (among others). That doesn't mean you HAVE to set up your speakers that way, but it's still a good idea to do so. And like John mentioned on that page, if you do have to raise your speaker above 1.2m for whatever reason, then it needs to be tilted down so that the acoustic axis is aimed at your ears again. That said, tilting a speaker introduces a whole new bunch of problems, such as reflections of the console/desk, and impaired psycho-acoustic perception of sound, so it has to be done with care and understanding. That's why I mentioned the "never more than 10°, some say 7°, I've never gone beyond 5°" comment.I got that number (which may not be exact) from this page on John's site http://johnlsayers.com/Recmanual/Titles/Acoustics3.htm
Depending on the make and model of your speakers, it might of might not be the cone of the tweeter. This is all about the acoustic axis of the speaker, which is the point on the front face where the combined sound of the woofer and tweeter appears to come from, and is generally at some point on the imaginary line that joins the center of the tweeter to the center of the woofer. It is generally much closer to the tweeter than the woofer, and therefore some people say to just use the tweeter as a rough guess, but for precision it is better to found out exactly where it is. Some manufacturers (such as Genelec, K&H, and others) publish that information for all of their speakers. Others will give it to you if you ask. Others don't know/don't care, so you probably shouldn't be buying their speakers anyway! :)The monitors I would soffit mount would be above the 1.2meter/4foot height(from center of cone, not bottom of cabinet)
Not sure what angle John used for that drawing, and I'm betting he did not show it on purpose, since all rooms are different. If he where to put an angle on there, then you'd see dozens of rooms built with that exact angle even when it was not appropriate! Fortunately, it's easy to figure out. The key is the position of your ears in the room: They should be at 38% of the room length from the front wall (theoretically "perfect" position, but NOT written in stone) and 1.2 m above the floor (which is the average ear height of most people when seated). So if your room is 10m long, then your chair should be set up so that your ears are 3.8 m from the front wall and 1.2m above the floor. Then set up your speakers such that they are about 28% of the room width away from the side walls, and angled inwards at about 30°. Now move them around so that the imaginary axes extending from the two speakers, intersect at a point about 30cm behind your head. Set up like that, those imaginary acoustic axes will be grazing just past the edge of your ears. The tilt angle of the speakers should be just enough so that the axes are lined up with the center of your ears at the point where they go past (in other words, the axis must get down to a height of 1.2 m at 38% of the room length). OK, BIG caveat! All of the above is theoretical perfection, but actual reality does NOT necessarily match! Those percentages, distances and angles are just goods starting points, not rigidly fixed positions in space. You won't be arrested by the Room Geometry Police if your speakers are actually angled 27° or 33°, or if you ears are at 41% or 36% of room length, or if your speakers are 26% or 30% of room width! You are allowed to change all of those a bit to suit the conditions of your room, without any problem.... provided that you understand the implications and the trade-offs. But that does give you the basis for figuring this all out, and getting things angled and positioned correctly.Would you know off hand know the angle that is used in John's drawing linked above? Or better yet, how to pinpoint the proper angle. I'm sure it all has to do with distance from the mix position.
The easiest way by far is to do this in SketchUp, then angle the things as needed to see how they end up. That's the way I do it.Is there an equation for this ? speaker height / distance from mix positon, etc?
I do have some I could show you off-line, in private, but I can't put them out on the forum in public since they come from studio designs I did for paying customers. Hope you understand! PM me.If you have any previous drawings of angled soffit mounted speakers that I could study they'd be a huge help!
Very positive! :) Those are my thoughts. For an RFZ design, that's a given: you have to slope the front section of the ceiling somehow, to force those first reflections way behind your head. However, once again the exact angle depends on each individual room, and the only real way to determine that is by "ray-tracing" inside a 3D model, using SketchUp or something similar. Generally you'll need more than 12°, though. 12° is for flutter echo, not for RFZ. - Stuart -I'm also curious about how to handle the ceiling above the mix position. I've seen in other designs where the ceiling slopes gradually upward from the front wall towards the mix position at around 7-12 degrees to its highest point, and then the angle either transitions to the typical 90(square) or to another gradual upward slope to the back wall of the CR. Thoughts on this???
Stuart,
Your advice on my hang-ups with my CR design is helping me move along. I'll post a sketchup soon. Honestly, I got so burned out on designing the CR that I had to start working on another area of the studio...
BOOTH 1
....yer gonna hate this..
The first iso booth I want to work up is the drum booth at the rear of the live room.
To refresh, i'll try to attach a jpg of the full floor layout here. If I fail, its on page 1.
The Existing dimensions of the area to be used is +/-11'H x 11'W x 11'D :twisted: :cop:
The existing roof trusses are 10' above the existing paver floor at the rear of the building and slope upward and inward to 14'. "shed" style.
If you were stuck with these dimensions, How would you best utilize the space within to make it into an iso booth? With its cubic dimensions and
not a lot of square feet to work with I'm on the fence on how to handle it. Obviously the dimensions are bad. But it can still be made into an acoustically pleasing isolated space though, right ? RIGHT!! :o
I've come up with 2 ideas so far of what I think would work. Knowing that cubic dimensions are bad I tried to angle the walls and ceiling to get it as much out of square as possible, but I'm not sure if I did a good job. Feel free to shoot me down!
With both designs I have the same question about using angles in rooms to help acoustics. When constructing the inner leaf of an iso booth with these dimensions, to throw the room out of square I'd assume you'd angle some walls. Would it be better to frame the inner leaf as a square and use angled slot walls to get the angles and absorbtion out of the open space of the room, or frame the inner leaf itself according to the angles?
Here are my 2 designs...
For much easier navigation, and saving about a million words in this text, you can download the SketchUp drawing from this link...
http://www.sendspace.com/file/qxttfm
On the sketchup, You will find 2 full inner and outer drum booth frames. The one on the left is DB 1, the one on the right is DB 2. The drawings layers match up on 1 & 2. All of the "Outer" named layers are real life existing. All of the "Inner" walls, ceiling, drywall, insulation, slots, etc, don't exist.
Have a look around the drawing and let me know if you think I'm heading in the right direction or if I'm way off. Any suggestions as to what to do differently would be awesome. or if you'd like to alter the drawing and send it back that'd be cool to! I'm open to any and all questions.
.....ready the firing squad....
Thx
Jason
A quick question I forgot to ask when we were discussing CR ceilings..
My previous question-
You're response-I'm also curious about how to handle the ceiling above the mix position. I've seen in other designs where the ceiling slopes gradually upward from the front wall towards the mix position at around 7-12 degrees to its highest point, and then the angle either transitions to the typical 90(square) or to another gradual upward slope to the back wall of the CR. Thoughts on this???
What about using a cloud over the mix position and front 38% of the room? As opposed to building an angled ceiling, what about keeping the ceiling flat and floating a cloud? my CR is x14'Wx20'Lx10'H. If I angle the ceiling I've got about 2 feet of height to play with within the 7.6' that is 38% of room length. I was planning to have a cloud from the beginning. I just want to know if having a cloud replaces the need for an angled ceiling since the cloud will be absorbing or at least deadening reflections from above. Or is there a middle ground? Thanks JasonVery positive! Those are my thoughts. For an RFZ design, that's a given: you have to slope the front section of the ceiling somehow, to force those first reflections way behind your head. However, once again the exact angle depends on each individual room, and the only real way to determine that is by "ray-tracing" inside a 3D model, using SketchUp or something similar. Generally you'll need more than 12°, though. 12° is for flutter echo, not for RFZ.
Back on the topic of Booth 1,
The exterior walls that surround the area for the booth are made of 2x6 studs. The outer side of the wall that is exposed to the outside world consists of a layer of 1/2" plywood with hardy plank siding on top. The inside is unfinished, just insulation in the cavities between studs. Would it help to put a layer of drywall up on the inside of the exterior walls to add mass and a better seal the inside of the building off from the outside world before framing the inner wall of the booth?, Or would doing so make it a 3-leaf wall and have negative effects?
From the outside world to the inside of the booth the existing layers and the ones I construct would go in this order....
Outside world-plank siding-1/2'ply-2x6 studs/insulated cavity- 1 layer 5/8"drywall- 2" air gap between framings-2x4 stud/insulation-hat channel on clips-2 layers 5/8" drywall(minimum)- Inner Booth
Sorry I didn't roll my last posts all into one :oops:
Jason