New build in Wales, UK

Hello everyone, this is my first post and first studio build from scratch. After reading and following this forum for many years I decided to finally get round to posting and asking for help, I hope I have followed all the rules correctly and that you can see the attached picture clearly. I'm converting an old stable block which would need to be completely rebuilt (recent storms in the UK blew it down to the ground!) so I decided to turn it into the studio I've been dreaming about for ages. It's right at the back of a large field with a woodland at the rear. We live on 5 and half acres of land with only a couple of distant neighbours but the rest of the property is a busy B & B with holiday cottages, so of course sound isolation will still be an important factor. I'd say the distance between the soon-to-be studio and the nearest building is about 70 meters. Here is a layout that I have been working on, although as time goes on I expect it will need to change. I may or may not construct the two iso booths in the live room, it will depend on budget and whether or not you guys see any design issues with them being there. The idea is to have many options while recording e.g. using the two iso booths for tracking guitar/bass with the drums in the main room. There is also a third iso booth at the back of the control room which will be mainly used for vocals. I want to use the space to the best of it's potential so please help me if you feel I am wasting space. Access to the live room from the control room is via a central sliding door (it's not very clear on the drawing) and the soffit mounted speakers will be above some small windows in to each corresponding iso booth. There will be concrete block work for the external walls with a 4" air gap between the internal and external walls. The floor is concrete and the height will hopefully be 12' internally, but may have to be reduced to 10'. The dimensions on the drawing are rounded to the nearest inch. I am not entirely sure about the layout of the live room yet, I just mocked up an idea for now but my first questions are as follows: 1. Regarding the dimensions of the rooms, does the general layout look ok or are there some major issues staring us in the face? 2. There are a lot of doors in my design, this is mainly because visual contact between all of the spaces is a big must for me but also because I want to be able to access the major spaces and in and out of the building without disturbing someone while tracking. I read that 'walking in to your air' is a bad thing. Does this still stand? Are there any doors that I can get rid of? 3. I am not sure whether the monitors mounted above small windows is a good idea or not? 4. I am planning to put bass trapping in the control room in the rear wall above the sofa (like an overhang, not seen in the drawing) and also in the front wall where the speaker soffits will be. Will this be the best I can do or can you suggest other solutions? That's it for now, sorry for the long post I just wanted to explain a fair amount now so that you have a rough idea of what I am trying to achieve. Thanks so much in advance, I wait patiently for your ideas

Hi there Paulus, and welcome to the forum! :)

recent storms in the UK blew it down to the ground!

:shock: Ouch! But perhaps a blessing in disguise, as now you get a studio instead!

I may or may not construct the two iso booths in the live room, it will depend on budget and whether or not you guys see any design issues with them being there. The idea is to have many options while recording e.g. using the two iso booths for tracking guitar/bass with the drums in the main room.

Having a couple of iso booths is generally a good idea, if you expect to be tracking large groups, or if you like a lot of separation for your instruments. However, I would put those at the other end of the live room, where you'll be still be able to see them through your glass sliding door. I'll get to the reasons for that below.

There is also a third iso booth at the back of the control room which will be mainly used for vocals. I want to use the space to the best of it's potential so please help me if you feel I am wasting space.

That might not be such a good idea, since the rear of the control room is where your bass trapping and first-reflection trapping goes. If you could figure a way to work that in, then maybe it would be OK.

Access to the live room from the control room is via a central sliding door (it's not very clear on the drawing)

Where does it slid to? That space seems to be about 6' wide, and by the time you allow for frames, trim, stops, seals and all the rest, you'll end up with an actual opening of about about 30". Is that enough? It might be, if you don't need to drag kick drums through there, but if your facility has to be compliant with regulations about wheel-chair accessibility, then that probably isn't enough.

the soffit mounted speakers will be above some small windows in to each corresponding iso booth.

That's the part I said I'd get to, above. If your speakers are mounted correctly, then those windows will be in just the right place for you to look at the kneecaps of your musicians... :) The acoustic axis of the speaker has to be 1.2m above the floor (47-3/4"). It is allowable to raise it sightly, but then you need to tilt it down so that it is still aiming at your ears. But you can't tilt it much! If you tilt it more than about 10°, you start creating psycho-acoustic issues that can affect the way your brain determines direction. In other words, you could end up hearing things in the wrong place in the stereo image. But before you get to 10°, there can already be issues with reflections from the top of the desk and the surface of your console. So 7° is about the practical limit, and I wouldn't do more than 5° if I can help it. So unless you have some really tiny speakers, or a really ling room, there's not much chance you can get your speaker up high enough to have those windows down below. Yes, I know that there are numerous photos on the web of studios with speakers mounted much higher than that, and tilted at larger angles, but those were either designed by experts who know how to deal with the issues, or are designed to cover the rear client seating rather than the mix position, or are supplemented by other speakers mounted down lower. So that's why I would suggest moving your iso booths to the far end of the live room, and putting bigger windows in them, for a better view. That would allow you to do your soffits and speakers correctly, and still have iso booths. You could also make the iso booths bigger, since there would be no need to separate them around the CR door: In fact, they could actually butt up against each other, with each being half the width of the room.

There will be concrete block work for the external walls with a 4" air gap between the internal and external walls.

Excellent. But what will the inner-leaf walls be made from? Drywall on framing?

1. Regarding the dimensions of the rooms, does the general layout look ok or are there some major issues staring us in the face?

With those two extra rooms at the back of the CR, there is no place to put your very essential bass trapping in the rear corners. You also have the client couch set back into an alcove on the rear wall, but that is going to be problematic, acoustically, and there is no space at all for trapping behind it. I would re-think the rear of the control room. It's also not a good idea to have the bathroom opening directly into the control room, for several reasons. Odors, for one, and humidity for another. Also, did you check those dimensions in a room mode calculator, such as Bob Golds' or Andy Mel's? You should confirm that you have reasonably decent ratios, or at least that you are far away from the bad ones.

3. I am not sure whether the monitors mounted above small windows is a good idea or not?

:) See above...

4. I am planning to put bass trapping in the control room in the rear wall above the sofa (like an overhang, not seen in the drawing) and also in the front wall where the speaker soffits will be. Will this be the best I can do or can you suggest other solutions?

You will need a lot more than that. The smaller the room is, the more bass trapping it needs, proportionally. For that size room, you need something like large superchunks in both rear vertical corners, plus under the soffits, plus the entire rest of the rear wall with thick absorption, and probably some of the wall-ceiling corners too.

That's it for now, sorry for the long post

Long posts are good! :thu: - Stuart -

Thanks for all your advice, I really do appreciate such detailed replies. I am especially grateful to know about the speaker placement issues, as I had always wondered about that. Like you said, I had planned to tilt them but by the sounds of it that would have been a pretty awful mistake. I'm in the process of drawing up another design now but just wanted to quickly ask one important thing: The builder who is constructing the basic outer shell is coming tomorrow to give a quote and I wanted some advice about what I should tell him to do regarding the roof and ceiling. Of course I will put a suspended inner ceiling but how should he construct the roof and outer leaf ceiling?

In response to your suggestions, how about this?

Access to the live room from the control room is via a central sliding door (it's not very clear on the drawing)

Where does it slid to? That space seems to be about 6' wide, and by the time you allow for frames, trim, stops, seals and all the rest, you'll end up with an actual opening of about about 30". Is that enough? It might be, if you don't need to drag kick drums through there, but if your facility has to be compliant with regulations about wheel-chair accessibility, then that probably isn't enough.

There will be concrete block work for the external walls with a 4" air gap between the internal and external walls.

Excellent. But what will the inner-leaf walls be made from? Drywall on framing?

1. Regarding the dimensions of the rooms, does the general layout look ok or are there some major issues staring us in the face?

With those two extra rooms at the back of the CR, there is no place to put your very essential bass trapping in the rear corners. You also have the client couch set back into an alcove on the rear wall, but that is going to be problematic, acoustically, and there is no space at all for trapping behind it. I would re-think the rear of the control room. It's also not a good idea to have the bathroom opening directly into the control room, for several reasons. Odors, for one, and humidity for another. Also, did you check those dimensions in a room mode calculator, such as Bob Golds' or Andy Mel's? You should confirm that you have reasonably decent ratios, or at least that you are far away from the bad ones.

3. I am not sure whether the monitors mounted above small windows is a good idea or not?

:) See above...

4. I am planning to put bass trapping in the control room in the rear wall above the sofa (like an overhang, not seen in the drawing) and also in the front wall where the speaker soffits will be. Will this be the best I can do or can you suggest other solutions?

You will need a lot more than that. The smaller the room is, the more bass trapping it needs, proportionally. For that size room, you need something like large superchunks in both rear vertical corners, plus under the soffits, plus the entire rest of the rear wall with thick absorption, and probably some of the wall-ceiling corners too.

I've redone the layout (see attached) and tried to incorporate the changes suggested. I'm not exactly sure whether or not the ISO booths are a good shape? I do prefer the size of them now although I am torn whether to have them or just one, nice big room. What are your thoughts? I've switched the positions of the WC and third vocal booth, and also changed the shapes of the rooms. I think this is a much better layout as yes, it had crossed my mind about the odour problem! - Good call, of course there will be a frosted window and I will have to work out a way to fit an extractor fan without messing up the isolation. The vocal booth and entrance will now have glass doors and I've made the entrance and WC 'one' as I do not see much use of them being separate and it would save money and space. The only potential problem with doing that would be in the case of extremely loud flatulence - but it's a risk I'm willing to take! What do you think about the new layout of the CR? I've moved the couch forward and filled the resized rear wall with bass trapping absorption. I've also elongated the two corner walls in order to fit the doors leading to/from the entrance and vocal booth. I've tried to sneak in some admittedly small bass traps in the rear corners but with the space allotted this is the only way I think I can managed to get some bass trapping in those corners. I would do away with the vocal booth, and entrance and have a larger CR if it wasn't for two factors: I need to have a WC there and I'd rather have a small entrance into the building in that position rather than having a front door on the side of the CR for example. I did have another plan but it involved walking into my air - while we're on that topic, can anyone explain why this is such a bad thing? Overall I'm happy with this new layout and hope that I am at least heading in the right direction now. I am not entirely sure what to do with the live room yet, regarding shape and acoustic treatment I just know that I want it to sound reasonably wet in the main part and of course dryer in the ISO booths. For now I've added some large bass traps in the corners of the main part which wedge into the diagonals created by the ISO booths. I am toying with the idea of having some foldback speakers in soffits in there to play rough mixes while tracking and also for feeding some low end back through while tracking, but again it's money. I may also put some small cupboards or drawers in the base of these to provide storage for some mics. Would I also need bass traps on the opposite corners too? Regarding dimensions, I have roughly checked if they are good ratios using a few different 'proven' ratio formulas, but I am not entirely sure which wall lengths to take the measurements from - is it internal floor space? is it including the built in absorption in corners etc? The rooms are not rectangular in most cases, so again, help with that would be much appreciated. Finally, to answer a couple of questions: 1. I am aware that the sliding doors may not provide a huge opening, I am looking into how much frameless panel doors might cost or perhaps making the opening a bit bigger, but this would change where the listening hot spot would be found, which as far as I am aware should either be in the first third or the last third of the room, but not dead centre, correct? Extending the opening would potentially push the monitors out further thus changing the hot spot somewhere around the couch... As to where the door will slide, well ideally it would be a door where only half of it slides over the other half rather than the whole panel sliding into a cavity in the wall. 2. Inner walls - The inner leaf will probably be 2 (3 if I can afford it) different thicknesses of plaster board with insulation in the cavities. Most of them will be inside out walls, but I may do some normal depending on what kind of surface I want in certain areas. The ceiling will be the same, but all will be inside out. I have a few more questions but I'll get to those once I know I'm on the right track with the layout. Thanks again for your boundless knowledge

Sorry, I don't think the pic uploaded properly, I'll try again...

anyone? :inn:

If I'm going to cut the insulation sheet for making super chuck bass trap. I think it's better to stick with factory cut. So, there're 2 ways I would cut it 1 cut 2'x4' sheet into 4 pieces 2 cut 2'x4' sheet in half and There are 3 ways I will make super chuck bass trap. depend on room's size and shape 1 1/4 of 2'x4' 2 1/2 of 2'x4' 3 2x 1/4 of 2'4 So you'll need at least 2' at rear corners for small room but for the size of your CR in this layout is quite large. I'd use 1/2 of 2'x4' or maybe 2' 10" to make bass trap. As I can see their not enough room for bass trap because CR entrance is in the corner. Building from scratch? No Existing interior wall? I think you better redo layout from the beginning. There are few options for Example 1 facing CR in other way (side way studio window) 2 Separate WC from the Studio Facility and make CR entrance more to the middle of CR instead of back corners. 3 Entrance reach Studio room first and enter CR via SR etc... Booth behind the control room is not good idea for me. You have to turn around to face with person in there and having door behind mixing position could be bad because most doors are reflective. It could have first reflection to mixing position and cause comb-filtering. Check out john's plans you might find idea to design your space. :D

Thanks for your advice and excellent information regarding super chunks. I've now taken your advice and redesigned the layout to something which should work much better (see attached). The plan has changed slightly due to the fact that we will now keep part of the existing external walls which will turn out to be a pretty good idea anyway considering they are made from solid stone and 18" thick. The front wall will be constructed from concrete blocks, here I've planned for 6" solid concrete blocks BUT was wondering if the light weight 4" aerated concrete blocks could work? I know that the 6" solid concrete blocks have more mass but that's part of the problem, they're so heavy! Trying to lug all of those blocks on site would be fairly difficult as there is no vehicle access to the building (it's in a large field) so they would have to be deposited about 70-100 meters away and then put on a small trailer on the back of a ride-on mower, by hand. If you guys say it's worth the effort and that the aerated blocks are a bad idea then so be it, but if I can save some man power and therefore time/cost, then do please let me know! We will also extend the width of the building from 18' to 22' which will now enable me to fit the CR the other way around. This also means that I can put a fairly extensive amount of bass trapping on the front and rear walls ( I will use a combination of the super chunk designs) as well as solving the rear window/ISO booth issue. This and the live room will now both be accessible via sliding doors on the two opposing side walls of the CR (I am aware of the reflections caused by the big panes of glass either side of the mix position but it seems to be the same in a few of John's designs so I've come to the conclusion that the visual advantages must outweigh the audio disadvantages, and in reality if the monitors are mounted correctly I think there will be minimal reflection problems - maybe I'm wrong?) Two smaller doors will provide access to a smaller ISO and the main entrance/WC/outside. I'm not sure what to do in terms of treatment in the live room, but I have been playing around with a window shutters/absorption panels idea which would enable day light into the room while tracking acoustic guitar for example but then the windows could be covered to avoid reflections from the glass when tracking drums. Just an idea. I could also fit a fair amount of super chunks into the live room, but I am suspecting that it will be hard to plan treatment until the room is constructed so that I can actually listen to how it sounds first. If you guys have any suggestions on that then please do let me know. I've based the CR dimensions on an 'ideal room' dimension from the SAE excel list of room ratios. With a 12' ceiling, luckily these wall dimensions have worked out pretty much spot on (minus a fraction of an inch or two). So guys, what is the verdict on my latest layout design? Am I almost there? Thanks again for all your advice and patience

This layout look good to me. Now you can treat rear part with bass trap and acoustic hangers But in my opinion I'd move booth to another corner (follow red arrow) So you can look into booth easier form your seat. Turning 90 degree to your side is the most you should turn. One of my acoustic instructor said "You have to see what you're recording" and John also said "Creating studios with no visual communication. There is nothing worse than recording someone you can't see." and I agree with Them. You have visual communication but you might not get full benefit. In the image dotted grey line show what are you going to see through those windows. It shows that you only see half of studio room. Maybe you should consider extend you glass view on your left to get more vision, more benefit from your studio room. Are you going to use sliding glass doors on your right? let's use both side (Same size too). I think it's good for acoustic symmetry of the room Cheers Ken

Hi again Ken & Stuart and anyone else taking an interest in this build :D Sorry I've been away for the past week but over the weekend I have been busy pondering over your suggestions and ideas. Thanks so much for your excellent advice, I completely agree with you and have now re-done my design. I really love this layout, it has everything that I need and the sight lines are as good as perfect. I've also repositioned the soffit mounted monitors so that the sweet spot is closer to 38% of the length of the CR, as well as extending the glass doors on each side to allow a much better view of each room. I was initially torn between sliding doors and windows as I wanted to keep the CR completely symmetrical if possible but that meant that I would either have 1 sliding door and 1 standard door both opening into the live room or 1 standard door only on the right side (which isn't the end of the world at all). But then after thinking about it for a while I realised that it would be much better to have sliding doors (even-though they would be more costly than windows) on both sides as it seems pretty long winded to open and close 4 doors just to get into one room. Then I realised that I hadn't any real storage so I thought I would squeeze a closet into a small area where my original ISO booth was which I can use to store noisy computers or mics or flight cases etc. It makes use of the space that would not be seen from the listening position as the sight line from the chair lines up nicely with the angled wall of the closet. The entrance to this closet is a little tight but I think it's useable as a closet space only. I do have a design without this additional closet too in which the glass sliding doors are replaced with large windows and the closet door opens out into the live room instead. I've also checked the reflection angles from the monitors hitting the glass either side of the listening position and to my knowledge they do not collide with the sweet spot, though I may have missed some other calculations that I haven't learnt about yet. The only real compromise that I had to make was losing a bit of absorption on the CR rear wall so that I could fit the two rear doors in, but there is still 2' in each corner plus 1' behind the couch. I've used super chunks in all the rooms mostly either 2x2 or 2x4 in all the corners that I can and some of the longer diagonal walls will have more low end absorption with Helmholtz Resonator slats on the surfaces. I want to continue talking about acoustics but first, what do you think of this layout :?:

That looks pretty good, actually! The only thing you should be aware of is that the "38%" is jut a guideline, not written in stone. It's a starting point, not a destination. Also, it applies to the the location of your EARS in the room, not the location of the point where the acoustic axes intersect. That will be several inches behind your head, in a room done properly.

I've also checked the reflection angles from the monitors hitting the glass either side of the listening position and to my knowledge they do not collide with the sweet spot, though I may have missed some other calculations that I haven't learnt about yet.

Hmmmmm... to me it looks like the reflections from the RIGHT speaker off the LEFT wall (and vice-versa) will hit your ears...

I want to continue talking about acoustics but first, what do you think of this layout

With the above caveats, it looks good. - Stuart -

Agree latest layout is looking good :thu: About side reflection you can angle of those slide doors on both side to create RFZ (Reflection Free Zone). I see there're still plenty of room to angle them. Isolation wise sliding glass door shouldn't be parallel as John wrote "I personally like sliding glass doors in studios because of the visual communication they afford. Like windows they can't be parallel so I always put them at an angle in the horizontal plane. (The vertical plane creates unbelievable problems with runners and seals.) Sliding doors can be made of either timber or aluminium." You can leave outside pair the way they are and angle the pair inside control room to create RFZ. then you will have RFZ at sweet spot and unparalleled slide doors for better isolation :D Cheers Ken

Isolation wise sliding glass door shouldn't be parallel as John wrote

That's a pretty old thread you are quoting, Ken! John no longer angles doors (or windows) since it isn't necessary: viewtopic.php?f=1&t=14215&start=4 MSM resonance doesn't depend on the shape of the cavity, just the depth at each point. If you angle a window or door, then one part of the cavity is not as deep as the rest, so at that point the resonance is higher, and the isolation is worse. It's best to go for the deepest cavity you can, to get the MSM resonance down as low as possible, which in turn means that the isolation is as good as it can be. - Stuart -

Oh thanks for your advise and Link Stuart Ken

Thanks guys for your enthusiasm and for replying! I understand everything that's been said and am glad that this current layout is heading in the right direction.

Soundman2020 wrote:

Isolation wise sliding glass door shouldn't be parallel as John wrote

That's a pretty old thread you are quoting, Ken! John no longer angles doors (or windows) since it isn't necessary: viewtopic.php?f=1&t=14215&start=4 MSM resonance doesn't depend on the shape of the cavity, just the depth at each point. If you angle a window or door, then one part of the cavity is not as deep as the rest, so at that point the resonance is higher, and the isolation is worse. It's best to go for the deepest cavity you can, to get the MSM resonance down as low as possible, which in turn means that the isolation is as good as it can be. - Stuart -

Thanks Stuart, I was also aware of this as I read John explaining the exact same thing as you on this forum a couple of years ago, so thanks for re-enforcing this point. Ken, I also get your point and will consider all the advice given. So if this layout is good enough for you guys then I will proceed with my plans. One thing I really cannot find enough info on is the use of light weight concrete blocks, or aerated concrete. As I've said earlier, it would be far easier to transport and use these for some of the external walls (minus the existing walls) but if it's not a good idea then I will just go ahead with the standard 6 inch heavy blocks. Anyone? Thanks!

One thing I really cannot find enough info on is the use of light weight concrete blocks, or aerated concrete...

What sort of surface density can you get with those options (in terms of kg/m2) for a wall built with those? That's important for figuring out isolation. - Stuart -

Soundman2020 wrote:

One thing I really cannot find enough info on is the use of light weight concrete blocks, or aerated concrete...

What sort of surface density can you get with those options (in terms of kg/m2) for a wall built with those? That's important for figuring out isolation. - Stuart -

Ok, so the data I have, accurate or inaccurate is: 730kg/m3

Great! That's absolute density, not surface density, but still fine if you know the dimensions of the blocks. 730 mg/m3 is about 1/3 the density of normal concrete, and around the same as drywall. But considering that those bricks are much thicker than drywall, you should have some pretty hefty surface density. Do you have the dimensions of the blocks? - Stuart -

Soundman2020 wrote:

Great! That's absolute density, not surface density, but still fine if you know the dimensions of the blocks. 730 mg/m3 is about 1/3 the density of normal concrete, and around the same as drywall. But considering that those bricks are much thicker than drywall, you should have some pretty hefty surface density. Do you have the dimensions of the blocks? - Stuart -

So, I don't have them to hand right now, and also they are available in different thicknesses. The ones I will use will be 450mm long x 215mm high x 100mm - 200mm wide.

I'm going to use light weight concrete blocks in my project too. Dimensions of the blocks available in my country 200x600 mm 8.33 blocks per square meter They are available in different thicknesses 75mm, 100mm, 150mm, 200mm and 250mm Many studios in my country use them but they use single 150-200 mm or 2 layers of 75mm-100mm with air gap. Transmission Loss in the catalogue that I have 100mm 38dB without plastering 43dB with plastered 10mm 150mm 43dB without plastering 46dB with plastered 10mm 200mm 48dB without plastering 50dB with plastered 10mm I'm going to use 150mm thick for my external wall because price is not too high :lol: Plus internal drywall it would be enough isolation.

So, I don't have them to hand right now, and also they are available in different thicknesses. The ones I will use will be 450mm long x 215mm high x 100mm - 200mm wide.

Assuming you use the 100mm ones, and have only one course, that would give you about 73 kg/m2 surface density, which is about six or seven times higher than for a single sheet of 5/8" drywall. In other words, it is equivalent to about seven layers of drywall. That would give you overall transmission loss of about 40 dB, just from that. When you consider that in conjunction with your inner-leaf, you should be approaching 60 dB of isolation, which is pretty good. - Stuart -

Amazing! That's great news. Thank you both for your excellent information and for taking the time to work it out for me. It is now making me wonder - if the isolation can be THAT good using aerated blocks, then how much better would the heavier blocks be? Well considering the studio is fairly far from surrounding buildings and it is out in the country, I think the aerated blocks will be suitable. What do you guys think of the shape of the live room? It looks interesting to me and I love that visually, there are no blind corners. I am not entirely sure what to do in terms of acoustic treatment, perhaps the acoustics section of the forum would be a better place to post? Just out of curiosity, do you guys have any suggestions?

The shape of the live room looks fine to me. Post here is better because it's about acoustic in your studio :D I think it is possible to hang Acoustic hangers in black area on both side of ISO Booth. and purple area would be bass trap. Attach fabric to stud to cover insulation behind stud Ken