Time to build a proper studio...

Hi everyone, Having spent the last 20 years working in living rooms [when single] spare bedrooms [when married] converted garages [when my daughter came along] and now having recently lost my rented outbuilding I have decided to take the bull by the horns and take out a lease on an industrial unit with a view to constructing a purpose-built studio. I'm a full-time professional producer/engineer/musician and I work mostly on my own. You can hear what I do here if you're interested: http://ottsonic.bandcamp.com That album was recorded in about 150 sq.ft in a barn I rented from my neighbour. The acoustics were appalling, the isolation non-existent and he just sold up and moved away so I'm currently without anywhere to work. The new unit is in the next village, ten minutes from my house. It is approximately 1000 sq.ft and is an ex-farm building of modern construction. It has a smooth [polished] concrete floor and is a steel frame building with a thin metal skin and fibre insulation panels cladding the inside. The long wall you can see in the pic is a single-thickness breezeblock dividing wall. The unit is half of a 2000 sq.ft building which has been partitioned. The other half is occupied by a chippie who makes bespoke furniture. Dimensions are approx. 5m wide x 19m long with a corrugated asbestos roof that pitches up to about 6m about 2/3rds along the length and down to 4m at one end and 5m at the other. It has a large [3.3m wide] roller-shutter door 4m from one corner on one of the long sides. It will have water and sewage by the time I move in which will enter the unit at the window-end at a location of my choosing. It also has three-phase power if I want it. It is weather tight but not draught-proof. The attached Sketchup file is pretty clear and accurate to about 50mm. 95% of my time I work alone with a computer and a pile of old synths and I work at very low volume. In 20 years of working in a semi-detached house I've never had a single noise complaint. For my next album, however, I've decided I want to get my drum kit out of the loft and invite my bass player friend over. This means I require isolation. I have read the wisdom contained within this site exhaustively and bought the Rod Gervais book and I fully understand the M-S-M principle behind the double-framed 2-leaf wall that seems to be the most efficient way of preventing sound travelling where it isn't wanted. I've also read Ethan Winers notes on acoustics and I understand the importance of dimension ratios with regard to room modes. I have some experience of stud-walling and I'm pretty handy with a drill/chop saw/spirit level/plumb line. I also have a friend who is a professional builder who is willing to assist me in the trickier parts, as well as a pack of strong friends willing to hump shit about in exchange for wine, snacks and/or my eternal gratitude. I have about £5000 to spend right now although this could stretch quite a bit depending on what I was getting for my money. When I mentioned in passing to my wife that the first piece of advice everybody gets on this forum was 'prepare for your budget to double' and that it could end up costing ten grand she nodded sagely and didn't leave me in a flood of tears. Which is good. One significant advantage to renting this unit is that it is part of a builders' merchants and within 20 feet of my unit is an inexhaustible supply of plasterboard, timber, nails, screws and what-have-you which can be forklifted straight into my unit on two minutes notice. The landlord/proprietor has given me a generous trade credit account and some really good prices on materials. Downsides are: The neighbouring unit is rented by a carpenter [really nice man] whose belt-sanders, saws, etc. make a right old noise and the breeze-block wall between him and me has a 100mm air gap round the top meaning that it sounds like you're in the room with him. It's a quite a long thin space, although having looked at some of John's designs on here [and what he managed to fit into a bloody shipping container] that is less of an issue to me now. Upsides are: It's close to my house. The rent and rates are incredibly cheap. The landlord is known to good friends of mine who attest to his upstanding character. It's in a builders merchants. I'm fully aware that just because I have 1000 sq.ft I don't have to use 1000 sq.ft. I'm quite happy for 1/3 of it to remain empty and use it for storing garden furniture and old bicycles for now. I can extend into the unused space as and when I need or want to. I'm also aware that a space like this could effortlessly swallow two hundred grand if I let it and that my budget won't buy me 'Air Lyndhurst'. What I actually require is a modest space for me to work on my music with enough space to set up a drum kit and a bass player. I don't need a separate recording area/drum room as I'm perfectly happy to have the drums in the same room as the mixer and monitors. This might sound mad until you remember that it'll be mostly me playing them and I don't want to have to keep running through a set of double doors every time I want to adjust recording levels on the floor tom. I've worked with a drummer in the control room [at RealWorld in the big room] and the technical disadvantages of that [considerable though they are] are kind of made up for in the creative advantage of all being in the same room together. The German band 'Can' set their studio up in just this fashion in the 1970s although I promise you I'm no Jaki Liebezeit. My main priority is a control room I can mix in and sufficient isolation so as not to have to listen to my neighbour's bandsaw all day and, conversely, not have him attack me with a chisel because I've had the same drum loop on cycle for three days. I would very much appreciate any advice and suggestions as to layout, construction and anything else. Thank you in advance and sorry about the long post. Ott.

"the breeze-block wall between him and me has a 100mm air gap round the top meaning that it sounds like you're in the room with him. " I feel your pain:) The block wall is almost the least of your concerns with isolation when you consider the overhead roof and the thin sheathing on the exterior metal framed building. A few things come to mind. One is that this block wall could require painting/sealing which will help to better the isolation. The other is that we need to address the over-the-top-of-the-block-wall leakage that has to be corrected...has to be. Those things out of the way we still have to deal with the existing thin metal structure, how much floor space you are willing to give up and where you want to place this new build within the current footprint. You want to get away from the open garage/shutter door as far as possible. Lot of potential here boss. The design is almost irrelevant as to what you are will ing to do to increase the existing isolation. The roof...the roof, the roof is on fire:) What kind of external noises outside of those dang carpenters, do you have to deal with? Heating and Air, all pesky issues...please consider them first, not last. I'll be around this weekend, I like your project, it is a challenge and I love a good challenge...so, be seeing ya...and welcome to the greatest show on Earth!!!

Thanks for the blast of enthusiasm Brien - just what I needed as I added up just the cost of the 4x2 i need for the framing. I'm aware that there is no point trying to make my draughty old farm building contain sound - I'm approaching it as a handy structure for keeping the rain off, burglars out and no more. I realise that whatever I build will have to provide virtually all of the isolation I require. At the moment I'm assuming I'll need to build a double-frame, two-leaf box which I intend to construct from 50mm x 100mm CLS timber and two layers of 12mm plasterboard for the walls and 50mm x 200mm CLS for the ceiling joists, all sealed as airtight as I can make it. The outer box will encompass the contol room inner box and the toilet/kitchen area [see attached sketchup file] whilst the inner box [control room] will be built inside this with a 25mm gap between the framing. The toilet will be just a single skin plasterboard and 50mm x 50mm box with a door, whilst the kitchen will be a salvaged sink unit with a fridge, kettle, toaster, microwave, 15bar pump espresso machine, Swedish fondue set and space for a hog-roast. The doors to the control room [single to the kitchen/toilet, double to the unused space in the unit] will be cheap old hollow plywood doors which I will open up and fill with plasterboard cut to size to make them heavier and more substantial. They will be sealed with soft, 10mm neoprene tubing glued round the inside of the door frame. The internal dimensions of the control room are chosen to conform with the 1[H]:1.50[w]:2.50[l] ratio recommended by Ethan Winer in the notes to his room mode calculator. For HVAC I will be using two ultra quiet fans drawing warm air out from vents in the roof of the inner box[es] ducted through homemade plywood plenum chambers with cool air being pulled in through two passive ducts also with baffle chambers. I aim to pick up a 2nd-hand recirculating AC/heater unit from salvage or eBay or somewhere with the radiator unit mounted on the wall in the unused space. There isn't much noise to contend with. There are a few trucks arriving to deliver supplies to the yard, the carpenter and the warehousemen who play Radio bloody One all day but that is it. I think if I build my inner/outer boxes well enough I'll be ok. I'll be working in a room inside a room inside a room. Or am I horribly deluded? The nearest residential neighbour is 200 yards away and never complains about the constant trashy radio music or the scream of my neighbour's blunt router. Attached is my latest Sketchup plan which I made whilst sitting at Newark Airport watching my flight to Arkansas get cancelled and Continental Airlines lose my equipment case whilst on my way to an important gig in the Ozarks. Feel free to rip it apart and don't spare the criticism.

Would it be feasible to incorporate the breeze block dividing wall as one leaf of my outer box, probably by facing it off with one layer of plasterboard and screwing the framing for that back wall straight to it? As long as the inner box [control room] and outer box are not touching I don't have to worry about the outer box being coupled to that dividing wall, right? My original plan was to have the outer box completely free-standing with a 50mm air gap between it and the dividing block wall but then it occurred to me that I would not then be able to screw the plasterboard to the framing unless I constructed the wall flat on the floor and then hoisted it upright with a block and tackle. Seems superfluous to me if I understand the two-leaf principle correctly. Oh, and I should point out that I haven't got round to the construction detailing on my Sketchup model so, except for the ceiling joists, the walls are just basic geometric blocks to illustrate dimensions. I will get round to adding in the construction details soon.

If you thought that was enthusiastic, this next one is going to rock your world! :) Room ratios have been around for decades and rooms in general have been designed to be pleasing visually and sonically by many builders/ architects. You only have to look around the building you are in right now to recognize this is not something new, it has been around you all your life you just were not aware of this. Alton Everest ( Master handbook of Acoustics - 4th Edition) presents 3 of the most widely used ratios developed by L.W. Sepmeyer (1965) and M.M. Louden (1971) The following table shows the ratios: Height Width Length _______________________________ _________ Sepmeyer A. 1.00 1.14 1.39 B. 1.00 1.28 1.54 C. 1.00 1.60 2.33 Louden A 1.00 1.4 1.9 B 1.00 1.3 1.9 C 1.00 1.5 2.5 Using the 8 foot ceiling height and Loudens first ratio produces a room 8 feet tall, 11 feet and a few inches wide and 15 feet and a few inches deep. That is about the size of a typical bedroom or the living room in many homes. The consideration for having a balanced proportional room is valid and worth the effort to use in any sound related type room. A few things to consider along the way. The measurements that are obtained from the ratios define the interior side of the wall. In order to use these measurements, you must determine how much and of what thickness your interior sheathing will be. This allows you to step out the placement of the sheetrock or MDF/OSB or whatever combination you may use, in order to establish were the actual framing will be placed on the floor of your build. For pure adherence to these ratios, a Ten(10) foot ceiling height is assumed, according to Mr. Everest. So to attempt to exploit a room for more accurate sound without using this predetermined height of ten feet negates the possible effect gained from the experiments. Trevor Cox ( http://www.acoustics.salford.ac.uk/profiles/cox/ ) stated in one of his papers that "ratios" are not scalable, something I have said for years but I do not have his credentials :) That means that, well, if the perimeters set out for the establishment of a desirable room ratio are not followed to the "T", you will not get the same results. Not to burden but John Sayers (World class designer and owner of this forum) has stated that he has never figured a room ratio in his life (paraphrase). The good news is that room ratios do have a redeeming quality. They keep us from building square rooms or WORSE, a cubed room :) So anything that gets you plenty of room volume and isn't divisible by any single number, one wall to the other or the ceiling, is still a good place to start. So we come to 12mm sheetrock. The information that I am about to type is taken directly from: Gypsum Board Walls: Transmission Loss Data | IRC-IR-761 | http://www.nrc-cnrc.gc.ca/obj/irc/doc/p ... /ir761.pdf Two layers of 13mm fire rated sheetrock on a single wooden frame with insulation, a 25mm gap between frames, another wooden frame with insulation and 2 layers of 13mm fire rated sheetrock on the opposite side away from the air space...a basic decoupled wall assembly. The comparison assembly is the same configuration but with 16mm (5/8 inch) fire rated sheetrock insteed of 13mm (1/2 inch) The STC rating of the 13mm is 65 and the 16mm is 69. Already mass is proving to be more effective since the 16mm is out permorming the 13mm by 4 points. But wait :) Look at the various frequencies of each assembly and we get another increase of the 16mm over the 13mm assembly. @ 50Hz the 13mm has a Transmission loss value of 21.6 but the 16mm steps it up to 26.7! This is the area that we work hard to control, the low frequency area. The 16mm sheetrock continues to out perform the 13mm sheetrock all the way up the frequency range. 13mm wall assembly STC 65 50 Hz 21.6 63 Hz 26.3 80 Hz 31.1 100 Hz 35.0 125 Hz 40.9 160 Hz 47.0 200 Hz 52.3 250 Hz 57.4 315 Hz 60.5 16mm wall assembly STC 69 50 Hz 26.7 63 Hz 31.8 80 Hz 36.6 100 Hz 39.5 125 Hz 44.6 160 Hz 51.3 200 Hz 55.9 250 Hz 61.8 315 Hz 64.9 You may have noticed that there was no mention of 12mm. Reason? Not enough mass since we already have much information that tells us "don't use no skinny wall sheathing" The 12mm wall assembly, if the data could be found would be less than even the 13mm fire rated wall assembly, the STC would be lower and the Transmission loss values would be lower as well. If you want to see the data in real time, download the document mentioned above and search for either: 2G13_WS90(610)_GFB90_AIR25_WS90(610)_GFB90_2G13 OR 2G16_WS90(610)_GFB90_AIR25_WS90(610)_GFB90_2G16

one thought - way not build the CR so the isolation ceiling is parallel to the existing roof? then you could build a false ceiling inside to high all the broadband absorbers (hangers) etc you will put up there. depending on if you are soffit mounting the monitoring or not, you will have a lot of room left over on the floor for additional treatments etc. definitely go with the 16mm fire code drywall layers instead of 12mm (unless you have no option (in which case - 3x 12mm vs 2x 16mm))...

Ok, I'm sold on the 16mm plasterboard. So far everyone has told me the same and my only reason for choosing 12mm is that I can get it for about half the cost. Obviously I can see that 'cheap' makes no sense if it doesn't do the job. Guilfo - I've considered a sloping ceiling but I'm not sure how to calculate the dimension ratios once I stray from a rectangular room. My intuition tells me that with non-parallel walls axial modes become less pronounced, although I'm also working out that with acoustics things quite often turn out to be counter intuitive. If anyone could give me a definitive answer or point me to where I might find it I'd be grateful. I'd still like to hear from anyone with an opinion on whether I can incorporate the breeze block dividing wall into my outer leaf or whether I should be completely de-coupled from the existing structure. Unusually for a project like this my main issue is excluding the noise made by my neighbours woodworking machines which emit sound largely between 1khz - 8khz, as opposed to containing my own low frequency sound. If I can't incorporate the existing wall into my outer leaf how should I go about building a stud wall 50mm from the boundary wall? If I try to do it conventionally there will obviously be insufficient space to get to the face of it to screw the plasterboard to the frame. Do I: A. Build it inside out, with the frame erected 50mm from the boundary wall and the plasterboard screwed to the inside of the frame? In which case, where do I put the Rockwool? B. Build it flat on the ground and then hoist it into place with a block and tackle? I can only imagine the mass of a 9 metre wall made of 4x2 and two layers of 16mm plasterboard and wonder if it wouldn't just buckle under it's own weight. I just finished reading the Rod Gervais book and feel I know a lot more than I did before I bought it. Highly recommended to anyone considering doing what I'm about to do.

"I'd still like to hear from anyone with an opinion on whether I can incorporate the breeze block dividing wall into my outer leaf or whether I should be completely de-coupled from the existing structure." Ah, well, yea, you should be completely decoupled from the existing structure, but there are still a few things to consider about the existing wall. One is that it will allow the passage of high frequency, assuming it is not already painted. If it is not, it should be...painted that is. A typical mass/spring/mass assembly is simple enough in that it requires a hard boundary, and air space and another hard boundary....your situation qualifies if constructed correctly. The attempt to figure out the axial modes once you develop something outside of an rectangular space will be far more challenging than we may be willing to take you to or even have the ability to do as such. Everest said to check it against (your current diffuse room) a same rectangular room of the same volume. But this has surely been upgraded and will prove to be not as effective as one might think. No disrespect to Alton Everest, not that I have the credentials to do as such, but the math is what it is.

Now I have worked out how to construct the outer wall so close to the existing dividing wall [build it flat on the floor and lift it into position] I've decided that any saving in materials would be far outweighed by the advantage, in isolation terms, of completely decoupling my studio construction from the existing dividing wall. Incidentally, I suspect the 100mm air-gap at the top of the dividing wall, between it and the asbestos roof, will be much more of an issue than the porosity of the wall itself and so I'll be tackling that first as a priority.

xSpace wrote:

The attempt to figure out the axial modes once you develop something outside of an rectangular space will be far more challenging than we may be willing to take you to or even have the ability to do as such.

That is the conclusion I have come to as well. Far better, I think, to build a room to known dimensions [I can achieve the optimum ratios even with my width issue] and then treat it accordingly with traps, resonators, absorbers etc. Additionally, I found this quote on Studiotips and it feels like solid advice:

Important! Building funny shaped rooms with canted walls and ceilings will not obviate the negative potentials of bad modal spacing - this practice only makes it impossible for non-experts to predict what the resulting modal structure will be [in fact such predictions are non-trivial even for experts]. Also, building funny shaped rooms usually ends up reducing the room volume from what it would be if a rectilinear room where built instead - and this makes all the problems of recording in a small room worse - because you made your small room even smaller! In short, there is no problem in small room acoustics that cannot be lessened by the simple expedient of building a larger room... making your room smaller so it can be funny shaped is a bad idea because you are making the fundamental problems increase in severity, and unpreditable in scope.

http://forum.studiotips.com/viewtopic.php?f=5&t=3315 As my construction will be dual-frame with 50mm x 100mm framing and 2 layers of 16mm plasterboard throughout, with outside dimensions of approx. dimensions of H3m x W4.8m x L7m can anyone advise me on stud spacing and ceiling joist size? I was planning on 400mm centres with 50mm x 200mm ceiling joists but from what I gather from Studiotips [unless I misunderstood] is that 400mm centres are overkill and could be detrimental and 600mm centres are preferable. http://forum.studiotips.com/viewtopic.php?f=9&t=52

Use wider stud spacing as code allows. Its generally always better to space studs 24"OC than 16"OC. at http://www.nrc.ca the files IR818 and IR761 and some in IR693 have more than enough data to cement this in as a firm rule.

There will be no other load on the ceiling aside from its own weight, with the weight of approx 70 sq.m [35 sq.m x 2] of 16mm plasterboard on each set of joists. Will 50mm x 200mm at 600mm centres be sufficient to support this or should I space at 400mm?

"Additionally, I found this quote on Studiotips and it feels like solid advice: Quote: Important! Building funny shaped rooms with canted walls and ceilings will not obviate the negative potentials of bad modal spacing - this practice only makes it impossible for non-experts to predict what the resulting modal structure will be [in fact such predictions are non-trivial even for experts]. Also, building funny shaped rooms usually ends up reducing the room volume from what it would be if a rectilinear room where built instead - and this makes all the problems of recording in a small room worse - because you made your small room even smaller! In short, there is no problem in small room acoustics that cannot be lessened by the simple expedient of building a larger room... making your room smaller so it can be funny shaped is a bad idea because you are making the fundamental problems increase in severity, and unpreditable in scope." If I can say this...Please do not re-post from this or other sites without including a link to the "original" topic. If you are not aware, John Sayers, the owner of this forum...that is all he does is create diffuse rooms with canted walls...and I am thinking that he (John Sayers) doesn't worry near as much as those that get caught up in "hard data", do about the challenges involved in thinking outside of the proverbial rectangular box. So if you can produce the author and link of this post, I would appreciate it, if you can not, we may have to amend this topic to reflect that.

xSpace wrote:

So if you can produce the author and link of this post, I would appreciate it...

http://forum.studiotips.com/viewtopic.php?f=5&t=3315 As I interpret it, all he's saying is that if you don't know what you're doing, keep it simple. I've amended my post to include the link.

Having read this thread [linked by Andre in lilith_envy's construction thread]: http://forum.studiotips.com/viewtopic.p ... nce#p11048 I'm concerned that the outer walls of my unit might form the third leaf in a three-leaf construction. To summarise, I'm planning to build a two-leaf, double-framed, room-within-a-room inside an industrial unit and I assumed, because there would be no sealed air-gap between the outer wall of my construction and the inner surface of the existing structure, the outer shell would not form a third leaf. The article above would appear to contradict that. Anyone able to provide an opinion?

Ottsonic wrote:

Having read this thread [linked by Andre in lilith_envy's construction thread]: http://forum.studiotips.com/viewtopic.p ... nce#p11048 I'm concerned that the outer walls of my unit might form the third leaf in a three-leaf construction. To summarise, I'm planning to build a two-leaf, double-framed, room-within-a-room inside an industrial unit and I assumed, because there would be no sealed air-gap between the outer wall of my construction and the inner surface of the existing structure, the outer shell would not form a third leaf. The article above would appear to contradict that. Anyone able to provide an opinion?

My opinion is that Paul had a leak due to a warped door and that the warped door provided a leak of sound, and when something of any mass was placed in front of this leak, the sound "seemed" louder since it now had another boundary to project from, since it was all in open space. In order for it to be a three leaf, the kind that scares people, you have to have completely sealed air space contained within the boundaries of the hard mass, as Stuart used to say, a hermetically sealed enclosure. Outside of that, it's putting the cart before the horse to assume you are in a situation that can be labeled as a potential 3 leaf environment when I do not see any pictures that suggest it one way or the other.

Thanks Brien, I assumed as much.

I've revised my design a bit and invite your comments. Internal dimensions are: H:3030mm W: 4230mm L: 5750mm Ratios are: H: 1: W: 1.40: L: 1.90 and room volume is 74 cu/M. Doors and acoustic treatments are not included - working on those next. I'm planning on using home-made framed Rockwool bass traps in each corner and along all wall/ceiling intersections, along with home-made Rockwool absorbers and some bought diffusers. Considering going with Auralex diffusers unless anyone has other ideas. Can't decide between using double solid wood doors [one in each leaf] appropriately sealed or one single 'super-door' as described by Ethan Weiner. I'm concerned that coupling the two leaves to frame a single door will compromise my isolation unsatisfactorily. Photo attached. Sketchup file is too big to upload, even when zipped. I'm happy to YouSendIt on request.