John Sayers' Recording Studio Design Forum Archive

Hi guys, I'm newbie on this, I'm currently building a new house and so a new studio. So far i've been working on a design like what is shown in the attached pictures. The size of the room is already fixed, it is in the space I have available for it so I can't change that, but I am trying to get the most of it working on the geometry of it avoiding parallel walls and parallel roof/floor. I'm considering double wall even that isulation is not my major concern, i'm much more interested to get a clean sound on the sweet spot. The studio is mainly to produce Psytrance, I don't use to play so loud, just enough to feel confortable to work for long hours. In the pictures I put some dimensions of the room where you can see the geometry of it which has the intention to send all the first reverberation to the back wall instead to the listener point. The room is made entirely with wood, is in the second floor of a geodesic dome and that's why the height in the front wall is different to the back wall. At this point, and I hope is not too late, I would like to ask for some advice on my current design and also ask for a couple doubts I have:
1. Any comment or suggestion of the design in general. Anything I could be missing that can be considering on the building process like i.e. add some gum material between the wood joints or stuff like that.
2. What would be the best material to cover the interior walls/roof or the less refractive material.
3. So far I was considering to flush mount my monitors (I have the Focal Solo 6 Be), but recently a friend of mine told me that is not good idea if the monitors are not designed for that. I read here there is a correction that can be done but I didn't understand how that works. I'll appreciate if you could give some guidance on this because has you can see in the pictures, if i'm not able to flush mount my speakers, I will need to move the listener point backwards and also the speakers will get too close to the wall, all things I'm trying to avoid.
4.The space between the two walls need to be empty or can be filled with more isolating material?

I would really appreciate your kind help and looking forward for your comments to include your suggestions. I already start the building, but I'm on time to make any adjustment if required.

Thanks in advance,

Best regards to you all.

Hi Heimdal,

Welcome to the forum! I'll try help you with some of your questions for you.

Heimdal wrote:1. Any comment or suggestion of the design in general.

With your room being quite small, you need to maximise acoustic volume as much as possible (How tall is the room?). That means not splaying any of your walls. It's a bit of myth that you need to do this.
If the purpose is to avoid flutter echo, it's much easier and usually cheaper to do with strategically placed treatments. Splaying your walls to allow for flush mounted speakers is not necessary (and a bad idea when it comes to isolation, unless you use a very complex design with passive speakers), your speakers can be flush mounted in frames built within a rectangular room. A huge benefit of flush mounting within frames in the room is you get to use the space behind the speakers within the frame for tons of absorption.

So the first thing I would do in your situation is to measure the maximum space you can get in your assigned location and design a rectangular box in that space, as wide, as long and as tall as you physically can squeeze in there. Then run those dimensions through this calculator: https://www.bobgolds.com/Mode/RoomModes.htm. See if the room dimensions pass the 3 R Walker BBC 1996 tests. If it passes 2 of the 3 it might still be workable anyway. Look for any yellow/pink or red warnings with the room modes. If you need help with this post back here.

Next thing: Your door shouldn't be in the rear wall if you can help it. Do everything in your power to avoid the door being in the rear wall. The rear wall is sacred Flip your room around and put the door between your speakers.

Heimdal wrote: So far I was considering to flush mount my monitors (I have the Focal Solo 6 Be), but recently a friend of mine told me that is not good idea if the monitors are not designed for that. I read here there is a correction that can be done but I didn't understand how that works.

There doesn't seem to be any problem at all with flush mounting your speakers. They look fine. They even have a front bass reflex port. I assume your friend was talking about the bass being amplified when flush mounting speakers. This is because they can no longer radiate in all directions, only forwards (the entire reason flush mounting is the best thing you can do for a small room). This effectively increases the bass sound pressure by 6dB. This is a relatively simple adjustment to make when you come to the digital tuning stage in the room design, using an equaliser, some speakers even have a switch that will cut the bass by 6dB for this very purpose, but don't worry if yours don't.

Heimdal wrote:4.The space between the two walls need to be empty or can be filled with more isolating material?

Always fill any cavities in your walls with light fluffy insulation to dampen resonance. This will greatly improve sound isolation. Do you know how much isolation you need. You need to plan for your isolation right away.

You don't seem to have any HVAC in your design, with a completely sealed room, you need to breath, you need to dump stale air and humidity. This isn't a luxury.

Heimdal wrote:What would be the best material to cover the interior walls/roof or the less refractive material.

The physical boundaries of your room ie. the walls should be made of normal construction materials that meet your building regulations. Usually plasterboard is the cheapest material, and gives good isolation when you use the thick stuff/fire-rated material.

The acoustic treatments need to be designed after you have sorted out your flush mounted speaker baffle, and baffle wing positions and ray-traced to make sure you are getting a reflection free zone around your mix position (the "sweet-spot"). The acoustic treatments can be faced with breathable cotton fabric/timber facing depending on their design and purpose.

Hopefully that gives you enough to start with

Dan

Hola compatriota, y muy bienvenido al foro! No somos muchos aquí de Chile, pero algunos hay.... ¿En qué parte de Chile vives?

OK, I'll carry on in English, for the benefit of the others. (the above is just a greeting to a fellow Chilean). Dan already dealt with many of these issues, so I'll just add some more to that.

Firstly, as he said, room size is one of the most important aspects, so don't make your room smaller than it needs to be be angling walls. It's a myth that walls should be non-parallel. The myth seems to have a life of it's own, and refuses to die, so you see it all over the place, but it is still a myth. Just make your room rectangular, and as as big as you possibly can.

The famous "equilateral triangle" is also a myth, believe it or not! Yes it does work for most rooms, but it is seldom the best layout in any give room. So you could use it, but you would not have optimum performance like that.

The size of the room is already fixed, it is in the space I have available for it so I can't change that,

What is the exact size of the empty space, with just the bare walls, floor and ceiling?

trying to get the most of it working on the geometry of it avoiding parallel walls and parallel roof/floor.

As mentioned above, that's not necessary, and it wastes space. In a small room like that, the number one priority is keeping as much air volume as you can inside the room.

I'm considering double wall even that isulation is not my major concern,

How much isolation do you have right now? Hpw much do you need?

i'm much more interested to get a clean sound on the sweet spot.

Then make the room BIG! Don't shrink it with unnecessary angled walls and ceiling.

In the pictures I put some dimensions of the room where you can see the geometry of it which has the intention to send all the first reverberation to the back wall instead to the listener point.

So you are attempting an RFZ style room? That's great. But do check that your angles are correct. You can use the "ray tracing" technique for that.

The room is made entirely with wood,

The existing room? Or the final inner-room? Or both?

is in the second floor of a geodesic dome and that's why the height in the front wall is different to the back wall.

Then it is understandable that you need to do some strange things with the ceiling, but do still try to maximize the space inside the room.

2. What would be the best material to cover the interior walls/roof or the less refractive material.

This is going to be a control room, so your goal should be to get as close as you can to the acoustic specifications shown in chapters 7 and 8 of ITU BS.1116-3. Your room interior will need careful design to achieve that. It's not as simple as just putting up some materials here and there. Tuning a control room is a bit more complex than that.

3. So far I was considering to flush mount my monitors (I have the Focal Solo 6 Be),

Excellent! That's the best possible thing you can do for your room. Flush mounting is one of the major keys to getting good acoustics in a small room. Or in any room, really.

but recently a friend of mine told me that is not good idea if the monitors are not designed for that.

Unfortunately, your friend is wrong. It is quite possible to flush-mount the vast majority of speakers. The only ones that cannot be mounted like that, are ones that have drivers on the side, top or bottom. As long as you only have drivers and reflex ports on the front and/or rear, then it is possible to flush-mount them. The Focal 6 Be is a fine speaker, and can certainly be flush-mounted correctly. Here's a thread about a studio where we flush-mounted speakers that were not designed to be flush mounted: thread about Studio Three Productions' studio Here's another one, where I flush-mounted the exact same speakers you are talking about: thread about a small corner control room

I read here there is a correction that can be done but I didn't understand how that works.

When you flush-mount a speaker, you get an automatic boost in the low frequencies, for complicated reasons. In theory, it can be as much as 6dB boost, and it starts at a frequency related to the width of the speaker, called the Baffle Step Response Frequency. That's why manufactures of speakers put controls on the back, so you can compensate for the changes in speaker response. You normally need to turn down the bass response a little, using those controls. It's a bit more complicated than that, but it is very possible to flush-mount (also called "soffit-mount") your speakers:

if i'm not able to flush mount my speakers, I will need to move the listener point backwards and also the speakers will get too close to the wall, all things I'm trying to avoid.

Actually, no! If you do not flush-mount your speakers, then there's a simple procedure that you can use to find the best location for the speakers and for your mix position... and it has nothing to so with any mystical "equilateral triangle"...

4.The space between the two walls need to be empty or can be filled with more isolating material?

If your are talking about an isolation wall, then use, the cavity must be filled with suitable insulation, since that's part of the MSM system.

I already start the building, but I'm on time to make any adjustment if required.

Then you already made a mistake! You should stop building right now, and design your room PROPERLY, for optimal acoustics.

- Stuart -

Thank you guys!! I'll take all your comments in consideration. You helped me a lot!! I'll let you know the results when I finish it.

Best regards!!

Heimdal wrote:Thank you guys!! I'll take all your comments in consideration. You helped me a lot!! I'll let you know the results when I finish it.

Best regards!!

Hi Heimdal,

We'd love to see something showing your design before you get too far in the build. Don't rush! There might be really important things you've missed/not considered that will create a massive headache or even ruin your build (this is especially easy to do when it comes to isolation).

Dan