Vocal Booth Design

Plans and things, layout, style, where do I put my near-fields etc.

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Soundman2020
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Re: Vocal Booth Design

Post by Soundman2020 »

Hi Pedro. Please read the forum rules for posting (click here). You seem to be missing a couple of things! :)

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Pedro
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Re: Vocal Booth Design

Post by Pedro »

Hi Stuart,
I am sorry for ignoring the forum rules and that I filled not our my profile, I was just too exited.
Fixed my profile and I hope that I am set up now.

About budget:
It should be in the U$ 2000,- to U$ 2,500,- for materials
I will do all the work myself.

I can not figure out of how to upload an image from my computer, therefore I used the picture from a website and hope this is OK ?
If some more information about me or my project is needed. please let me know.

Kindest regards
Peter
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Re: Vocal Booth Design

Post by Soundman2020 »

Much better! :thu: And Feliz Año Nuevo to you! :)
I am living in the boonies and the noise problem is not too bad outside here, average about 8-10 db (birds), when a motorbikes pass by it goes up to 40 db.
I'm not sure how you got a reading of 8-10 dB for the ambient level, but that isn't correct. 10 dB is the level you'd hear in a typical well isolated anechoic chamber or acoustic laboratory, and most common SPL meters are not capable of measuring such low levels. About the lowest you'll even hear in real life, is around 25 dBC. Maybe you measured that with an iPhone app, or something like that? You can't trust those: they are way inaccurate. Get a proper sound level meter, decent quality (such as an Extech or Galaxy): they go for around US$100 on Amazon or e-bay. I'm not aware of any common SPL meter that is capable of measuring below 25 dB: most don't go below 30. Only sophistcated (and expensive!) meters go lower than that.

A more realistic ambient level for a rural area with birds, would be around 30 to 35 dB(C). And when the motorbike passes close by, I'd expect upwards of 80 dB(C).

So I'd say that the levels you measured are very inaccurate, and I'd suspect that you measured them with a cell phone app. I would not trust those levels at all, since they are unrealistic.
I am living in Uruguay and to come by all this high tech Materials is not possible for me, at least not for an reasonable price, they charge her 100% import taxes on most goods, also shipping costs are out of this world.
That's fine. You can still build your place with whatever materials are available. We might need to do some changes to the structure to compensate, but you can still build it with typical common building materials.
What is available here: Wood (not straight and low quality), MDF, Plywood (no exterior Ply available), Gypsum Board (China made), Bricks, Cement, Cement Blocks, just basic building materials are available.
Perfect! All of that is usable.
Insulation: Glass wool (very low quality), Rock-wool sheets, Styrofoam
The Styrofoam is useless: No acoustic benefits at all. If the fiberglass is poor quality, then just stay with the mineral wool. Do you have a link to the specifications for that?
So I wonder if I could build the walls and ceilings with bricks and cement, those are the cheaper materials available here.
Yes you can. No problem at all.
I could not find any plans or information´s about building with concrete and bricks or concrete blocks.
In many countries, it is expensive to do it that way, but where we live, it is sometimes cheaper. And better! Bricks and blocks have much higher mass than drywall, plywood, or MDF, so you get better isolation.
Building double walls would be no problem I guess, but how and what to use for insulation on the outside and inside ?
If your outer wall is brick or block, you can seal that and finish it any way you want. Exterior grade plaster ("stucco") would be good. Your inner wall could be brick as well, or it could be drywall on studs.
Is Styrofoam (which is available here) of any use ?
Nope. Nothing. Nada. Como dicen aquí en Chile: "Vale callampa!".
How to build a simple roof, maybe just a standard flat tin roof or a concrete slab (with grass on top) ?
Not a tin roof, but in that data sheet you posted they do show a "beam and block" type system, which would be great. Or a poured concrete slab would be even better. Seal that well, and you can put whatever you want on top.
For room treatment I will have to import Auralex Foam products I guess.
Not necessary! You can build your own treatment using wood, MDF and mineral wool insulation. That's all you need.
Pedro
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Re: Vocal Booth Design

Post by Pedro »

Hi Stuard,
thank you very much for your loooooong detailed answer and all the great info's.

Yeah, I measured the dB levels with an application on my computer, had no idea that the results are totally useless.
So why peoples build this useless programs at all ???
Does not mater, at least I have learned something ...

Just realized that we almost neighbors, how small is the world ;-)

I am feeling, that a double brick wall is the way to go for me, gives me good insulation and materials are easy available, affordable (compared to lousy wood) too.

A concrete slab as roof is very common here and will last me forever without much maintenance, could even put some grass on top of it ... will keep the summer cool and the winter warm ;-)

Great idea to build my room treatment out of MDF and Rock-wool, can be done locally and saves me the hassle of importing foam products ...

Must source out Rock-wool sheets, but I guess the heavier and tighter, the better.
Glass-wool is readily available here everywhere and cheap, maybe I use that and when I pack it tight together it could work too ???

Do I really have to flock out 100 Bucks to measure the exact DB levels ?
I just build a bit thicker walls to be sure NO sound enters into my room ;-)

What I have in mind, based on John Sayers design on the beginning of this threat (Booth.skp)
I am thinking of building two 20 cm (or maybe 30 cm for the outside wall) thick walls with a 10 cm gap (what would be the right distance) between them, this should give me adequate insulation.

Maybe two 12cm/12 cm walls would do the job too, I have no idea ?

Outside wall sealed with plaster, inside wall 10 cm Rock-wool on the wall on a 2" x 6" wooden frame (5 cm gap between wall and insulation), covered with wooden panels (10 mm), to make it a bit cosy.

On the inner walls Absorbers made of MDF and Rockwool and maybe some Diffusers too.
Actually the inner insulation could be used as Absorbers, when covered with cloth, instead of wooden panels.

Bass-Traps in the corners would not hurt too.

15 cm Concrete slap for the floor, with some kind of carpet on top, or better just bare not smoothed concrete. ( I have a dog as assistant ...)

10-15 cm concrete slaps for both roofs, inner and outer.
-> What would be the right gap between the two walls and the roof slab ?

Doors made of double walled Steel, heavy insulated with 10 cm Rock-wool or massive wooden doors (8 cm plywood (the later I could build myself, which I prefer).

1 (2) Small window(s), about 80cm x 30 cm, (just to let some light in) with 10mm/8mm double glass in each wall.

Ventilation with quiet solar driven computer fans, mounted outside the building, air goes trough trough foam insulated sound traps.
This system could be used for blowing warm air (caravan gas heater) too, for the nasty winter time.

This construction would be a bunker, that's for sure and probably cost me a small fortune ;-)

If it gets too costly, I postpone it for next year, no point to safe money and then I have the same what I have now, disturbing noise all the time ;-)
I really like my birds around me and enjoy them, but not when I press "record" ...

Maybe go even completely under ground ???
But this could give me problems with moisture ... also the entrance is not easy to build, it would be a water trap too.

What do you think about my ideas ?

I am still cracking my head about the right size ?

I will use this building as my working place (editing) too, not just for recording.
Therefore I need a small desk for my computer, a comfy chair and maybe some shelves, which could act as diffusers.

I do only voice overs, therefore no need to house big bands with instruments ...

I know, the bigger the better, as always, but sadly I have no private access to a gold mine ;-)

What size would you recommend ?

One more question.
As there should be no parallel wall on the whole construction, it will look a bit strange to outsiders (for me no problem at all, I like strange things)
Would it be OK to build the outer wall symmetric and the inner wall to the right shape (just a thought) ?

Would the so often recommended diamond shape bring big huge benefits ?
I actually like the shape and it could look quite nice in my garden, beside my "Pyramide".
I like also the octagon shape, but I guess this one is too symmetric and will cause acoustic problems.

What about a PYRAMID shape, this would be great when it would work, would bring me two benefits, a recording studio and a great place for meditation and energy work.

A Pyramid would be my absolute favorite, but a bit difficult to build. ( I like challenges)

Wow, again many questions for you.


Thank you very much in advance for all the time you spend for me.

Kindest regards and enjoy your day
Pedro
"Our life is what our thoughts make it." - Marcus Aurelius
"Magic is believing in yourself, if you can do that, you can make anything happen." Goethe
Soundman2020
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Re: Vocal Booth Design

Post by Soundman2020 »

Yeah, I measured the dB levels with an application on my computer, had no idea that the results are totally useless.
So why peoples build this useless programs at all ???
The program is probably OK... but you need to calibrate it first! The computer just receives a digital signal from the mic and interface, but it has no way of knowing what that signal represents in the real world. You have to tell it that the level it is seeing is actually XX.X decibels, and from then on it knows how to calculate all other levels (provided that you don't change any settings, or use a different mic!).
Just realized that we almost neighbors, how small is the world
Así es, vecino! :)
I am feeling, that a double brick wall is the way to go for me, gives me good insulation and materials are easy available, affordable
Right. It seems like it will be your best option.
Must source out Rock-wool sheets, but I guess the heavier and tighter, the better.
Nope! For mineral wool, you need to find stuff that has a density of about 50 kg/m3, roughly. That's the optimum, for most acoustic applications. If you use stuff that is heavier than that, then it won't do so well at absorbing low frequencies. And if you use stuff that is much lighter than that, then it won't do so well at absorbing high frequencies. But probably anything in the range 40 kg/m3 to about 60 kg/m3 would be reasonably good.
Glass-wool is readily available here everywhere and cheap, maybe I use that
If you use fiberglass, then the optimum density is about 30 kg/m3, and you could use anything in the range 20 kg/m3 to about 40 kg/m3. The properties of different types of insinuation are not the same: it is important to use the correct density of each type.
and when I pack it tight together it could work too ???
Nope! You should NEVER compress insulation much, as that changes it's characteristics: it makes it more dense, so it becomes worse for low frequencies. It also prevents the tiny fibers from moving as they should, so it is less efficient at absorbing sound. Just leave it as it is.
Do I really have to flock out 100 Bucks to measure the exact DB levels ?
You will need that meter for many tests along the way, and to calibrate REW when the time comes to do room tuning, and to calibrate your speakers when you do the final setup, and to make sure that you are always mixing at sensible levels, always, for ever....

So yes, you need a meter. And 100 bucks is only a very small fraction of what it costs to build a studio, so you won't even notice spending that little! :)
I just build a bit thicker walls to be sure NO sound enters into my room
Nope! Isolation does not necessarily depend on thickness, and increasing the mass of a single-leaf wall does not have much effect on the total isolation.... It's a lot more complicated than that, and is not intuitive... :)
I am thinking of building two 20 cm (or maybe 30 cm for the outside wall) thick walls with a 10 cm gap (what would be the right distance)
Right distance for what? That's like you asking me "I'm going to get 3 liters, is that enough?" Enough for WHAT? Unless you first now what spectrum you need to isolate, and what level you need to isolate at each frequency, then I can't tell you of 10cm is enough, too much, or not enough. There are equations for calculating all this, but I need the input numbers ....
Maybe two 12cm/12 cm walls would do the job too, I have no idea ?
Neither do I, unless you give me the data I need! :)
Outside wall sealed with plaster,
Right!
inside wall 10 cm Rock-wool on the wall on a 2" x 6" wooden frame (5 cm gap between wall and insulation),
Why do you want a gap? An MSM isolation wall is more effective when the cavity is completely filled with insulation, and it is touching both leaves, but not compressed very much.
covered with wooden panels (10 mm), to make it a bit cosy.

On the inner walls Absorbers made of MDF and Rockwool and maybe some Diffusers too.
Actually the inner insulation could be used as Absorbers, when covered with cloth, instead of wooden panels.
No, no, and no. You do not ever want to create a 3-leaf wall if you can avoid it. That will make your isolation worse, not better. You can only use diffusers if the room is large enough to allow it. Diffusers have lobing patterns up close: you have to keep them far enough away from your ears that the lobing does not affect what you hear.
Bass-Traps in the corners would not hurt too.
It's not that they "won't hurt": it is that you absolutely MUST have them! It is a small room: it will need many large, deep, bass traps. That goes without saying.
15 cm Concrete slap for the floor, with some kind of carpet on top
No. Carpet is a bad idea in a studio: it does the opposite of what you need, acoustically. Forget carpet.

Doors made of double walled Steel, heavy insulated with 10 cm Rock-wool
No. Never use hollow-core doors for a studio: the cavity inside is a resonant system. Use only solid-core doors, that are very, very massive.
1 (2) Small window(s), about 80cm x 30 cm, (just to let some light in) with 10mm/8mm double glass in each wall.
No. Double glazing panels have very lousy low frequency isolation, and having two double panels means you have a 4-leaf system, which has terrible low frequency isolation! What you need is thick laminated glass. One pane of 22mm laminated glass in the outer leaf, and another one in the inner leaf. That's all. And make sure you get laminated glass that has the special acoustic PVB: it is a bit better than that standard PVB.
Ventilation with quiet solar driven computer fans, mounted outside the building, air goes trough trough foam insulated sound traps.
No, no and no! HVAC for studios is VERY complicated: you can't do it the way you suggest. You need silencer boxes, to stop the sound going in and out while allowing the air to flow, they need to be the correct size for your room, you need proper HVAC fans that move the right volume of air at the right speed when faced with the static pressure created by your system: computer fans are not meant to be used with any static pressure load at all! They would simply stall and do nothing. You also need the correct size ducts and registers, and you need a mini-split system to heat, cool, and dehumidify the air.

Yes, you do NEED all of that: you cannot do a studio without it.
This construction would be a bunker, that's for sure and probably cost me a small fortune
Right! :thu:
If it gets too costly, I postpone it for next year, no point to safe money and then I have the same what I have now
It will take many months to design the studio correctly: If you hire a studio designer to do it, it will take two or three months, probably. If you do it yourself, it will take MUCH longer, as you will first need to learn all about acoustics (at least 4 to 6 months), then you will need to learn all about studio construction techniques (another 3 or 4 months), then another 4 or 5 months to do the actual design. So yes, I'd agree that you should plan to start building in 2017, if you want to design it yourself. Or perhaps in May or June, if you hire a designer to do it for you.
As there should be no parallel wall on the whole construction,
Why???? :)

That is a myth. Many people think that the walls in a studio HAVE to be non-parallel, but that simply is not true. It is very possible to build a studio that has a rectangular shape, with parallel walls... if it is design properly, and treated properly!
Would the so often recommended diamond shape bring big huge benefits ?
No, none at all: that's another myth...
What about a PYRAMID shape,
:ahh: :cop: :cen:

:)


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Pedro
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Re: Vocal Booth Design

Post by Pedro »

WOW,
thank you very much for answering all my questions in this great detail, a BIG lesson for me, indeed.

I would have done everything wrong and wasted a lot of money too.

Now I see clearly that building a studio is not a small task and involves a lot of knowledge and planing, not talking about the full truck load of money ..
So I have to calm down now and start educate myself to get more insight into this topic.

Could you please recommend me good literature which will help me on my way ?

Are there any good stock plans available for small home studios which are worth the money ?
This could save me a lot of troubles.
The internet is full of crap and it is very difficult to sort out the right staff.

To hire a studio designer will probably be out of my financial range ;-)

In the meantime I have to work with what I have :oops:

I run on a small solar power system, so this would have to be upgraded too ...

I had not in mind to build a HVAC at all ...

Will let sink everything into my head and try to figure out a doable way for me.

The more and more I think about that, I feel that a proper sound studio would maybe be a total overkill for what I am doing.
I am just recording voice overs for self hypnosis products (no music recordings at all), not creating state of the art music compositions, just simple mixing (putting my voice over ready made background sound)

Of course, a proper studio would be the optimum, but I have to get going first to make some money to afford one ;-)

I started driving a car on a 20 year old car, the Ferrari came just a bit later, just kidding ;-)
I need a minimum approach to get me going, the studio is the end goal of course .....

TO GET ME GOING, would a tiny vocal booth do the job for me (for voice recordings) ?
Yeah, I know, that's a very clever question ;-)

My products will be listened via headphones all the time
, therefore I should do all my mixing via headphones too I guess, to get a good and optimal quality product for the user. (probably have to mix via headphones to get it right)

Thanks again for all the time you spend for me, I really appreciate that, saves me a lot of mistakes.

Kindest regards and enjoy your day
Peter
"Our life is what our thoughts make it." - Marcus Aurelius
"Magic is believing in yourself, if you can do that, you can make anything happen." Goethe
Soundman2020
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Re: Vocal Booth Design

Post by Soundman2020 »

Could you please recommend me good literature which will help me on my way ?
I'd suggest two books: "Master Handbook of Acoustics" by F. Alton Everest (that's sort of the Bible for acoustics), and "Home Recording Studio: Build it Like the Pros", by Rod Gervais.

The first one will give you the background of basic acoustics, everything you need to know to understand how sound actually works (it doesn't work the way we imagine it does). The book is meant for everybody, and doesn't get into the complicated math: simple explanations and examples, with basic math, graphs, pictures, etc.

The second book is more about how to actually design and build a room.
Are there any good stock plans available for small home studios which are worth the money ?
Not really, because all rooms are different. Unless your space is exactly identical to what the plans were meant for, you'll have to adapt them anyway. And in order to adapt them, you still need to understand acoustics, construction, etc....

However, there are many examples on the forum of studios that forum members have built, with diagrams, plans, photos, descriptions, etc. so you can see how they went through the process, and how their designs changed as they learned more. There are also many examples on John's own website, that show studios he has designed and built. You can get a lot of ideas from those.

The internet is full of crap and it is very difficult to sort out the right staff.
:thu: Very true!
To hire a studio designer will probably be out of my financial range
Maybe not as much as you think, but a studio designer can actually save you money, because you won't make the design mistakes that first-time studio builders often make, and you wont need to go back, take things down, fix them, do them again.... You will also not fall into the trap of buying expensive materials that you don't need, or building expensive things that you don't need.... The fee that you would pay a good studio designer, you will get back by NOT wasting money on all of those mistakes!
I had not in mind to build a HVAC at all ...
You will need it! A studio must be sealed air-tight in order to work properly... but you need to breathe... :)
I am just recording voice overs for self hypnosis products (no music recordings at all), not creating state of the art music compositions, just simple mixing (putting my voice over ready made background sound)
Then your needs are simple, you only need a simple isolation solution, and you only need design and treatment for voice, not for music. That makes it a bit easier. Your design will not need the extremes that many forum members have to go to.
I started driving a car on a 20 year old car, the Ferrari came just a bit later, just kidding
Cool! My Ferrari is doing great as well! I have already saved about 3% of what I'll need to buy it! :) :shot: In about a hundred years from now, I should have enough! :!: 8)
I need a minimum approach to get me going, the studio is the end goal of course .....
Then I would suggest that you design the complete studio, with everything you will need, but only build the most basic part of it now. Then you can add the other parts in later, as you need them. So design the entire building, complete, and build the outer shell with the roof, but then just build the minimum inside that is just enough to do what you need now. Then when you need other parts, you can add those, one at a time.
My products will be listened via headphones all the time, therefore I should do all my mixing via headphones too I guess, to get a good and optimal quality product for the user. (probably have to mix via headphones to get it right)
Not really! Most people listen to music on earbuds these days, on their cell phones, but I don't know of anybody who mixes on ear buds! :) You should still mix on speakers, because you need to hear the full sound of what you are mixing, with both ears, then you check the final mix on headphones to make sure it sounds good there too. You can hear details on the speakers in a room that you won't be able to hear on your specific headphones, but that other people might notice on theirs...
Thanks again for all the time you spend for me, I really appreciate that, saves me a lot of mistakes.
:thu: That's what the forum is here for! :)

Saludos, suerte, y cuente conmigo para aydarte en este proceso!

- Stuart -
Pedro
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Re: Vocal Booth Design

Post by Pedro »

Hi Stuart,
thanks again for your detailed answers and suggestions, great as always :D
Have already the book from Rod Gervais, good read indeed.
Will get "Master Handbook of Acoustics" too ....

Yeah, have to study a lot more, this forum is a great resource and I am very glad to found it.

John's samples are really great and I guess it will be the best way for me to follow his designs very closely.
The design of the first post in this thread looks great for me and should be quite affordable too.

Will have to plow trough more in this forum to find more ideas and see what it is possible.
If a day would have 40 hours, that would be great and helpful too ;-)

The HVAC system will give me a BIG head ache, because I have no grid power and to run that on solar power would cost me a fortune.
Therefore Heating will be done with a caravan gas heater or a small wood stove and air ventilation can be run easy via solar, air conditioning I have to forget at all.
Yeah, a simple isolation solution will do it for me, should not be too difficult to achieve, all I have to do is getting the bird's noise out of my way ;-)

About the Ferrari, we will be ready about the same time, so we can have our first run together ;-)

Thanks for your suggestion about building a real Studio straight away, that's the right approach.

Speakers will be the next power hungry suckers, maybe go for passive ones, if they need less power via a small 12 V car amplifier ????
The passive Behringer 1C-BK speakers could maybe do it for a start, not expensive and have quite good revues from user.

Do I need an extra amplifier for passive speakers ? (I run everything trough a MOTU Ultra Lite mk3)
If yes, what kind of amplifier would you suggest ?

After making a few millions with my products I can upgrade to proper equipment and put the Behringer's into my bath room ...
Therefore it would be wise to build my studio a bit bigger too ;-)

So my next step is to educate myself to make a wise decision and design an almost perfect studio for me ...

For building materials I guess it would be best to go for wood and plaster board, for this system there are endless samples out there which are proven designs and I could quite easily follow this approach.
So far I could not find any literature about building small studios with concrete and bricks.
I am a woody too, have build 3 huge wooden boats already, 20m Catamaran, 13m Catamaran and a 17m Monohull, so this approach would fit me probably better, concrete is not my preferred material.

Also my house here is wooden and a nice studio in wood would fit quite well ;-)

Thanks again for all your help and enjoy your day :thu:

Muchas gracias a ofrecerme su ayuda con mi proyecto ...
Saludos cordiales
Peter

PS: got the "Master Handbook of Acoustics", what a treasure, finally some info's about building with concrete and bricks, thanks for your recommendation :thu:
"Our life is what our thoughts make it." - Marcus Aurelius
"Magic is believing in yourself, if you can do that, you can make anything happen." Goethe
Dixie
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Re: Vocal Booth Design

Post by Dixie »

Hi everyone,

After weeks of DIY closet conversions, acoustic foam sales pitches and “my new home recording studio“ videos I was delighted to finally come across this forum and John’s very generously downloadable recording booth design. As much as I loved the design, at the time I thought it was probably overkill for our requirements and decided instead to treat the room with a locally available generator insulation foam. That was after trying to get some Knapf rigid panels shipped in and having them ransomed by customs here in Bali who wanted USD $3,000 to clear USD $300 worth of panels, but that is another story.

I have included some photos of the space, which has a solid brick wall covered with insulation on one long side, and a glass sliding door covered by blackout curtain on the other long side. The short wall behind the TV is brick with a glass insert door behind blackout curtain. The other short side wall is brick with a large hollow core wooden door with Balinese carvings at the top that penetrate the door. The floor is ceramic tiles laid on a concrete slab. The ceiling is timber panelling (3mm?) with nothing but air between it and a sloping tiled roof. That is our “casting couch” in the middle of the room :lol: (surprisingly we are still married although this booth could put an end to that).
current setup 1.jpg
current setup 2.jpg
current setup 3.jpg
current setup 4.jpg
We’re recording ADR for our online videos and this setup has worked surprisingly well. The recorded dialogue sounds great and the treatment has been effective at eliminating nearby motorcycles and roosters from our recordings. It has also worked well for mixing the recorded vocals with the other sound elements in our videos (area sound, foley & music).

So why am I posting then? Recently we have been plagued by residential construction noise. Our recordings are now picking up concrete mixing and hammering from next door (about 15m away). The tile cutting is still to come. Fortunately there are 4 solid walls between the noise source and the microphone but that will drop to perhaps two once they start working on the second story and roof. It has brought us to a complete standstill because they are working 7 days a week and since no notice was given (which is normal here) we’ve been caught completely off guard.

At least now I have an excuse to build John’s booth, which will hopefully make our audio sound even better and allow us to continue recording while they are building. I have included a diagram of the proposed layout (the room is 3.15m high). I understand that mixing in the room may no longer be an option but that is preferable to having nothing to mix at this point.
room layout.jpg
Before getting to my questions, I’d just like to add that it is truly humbling and inspiring to witness the dedication to perfection and commitment to craft on this site. Sincerely, thank you VERY much for sharing your knowledge with the rest of us (especially the prolific Knightfly & Soundman2020).

In terms of my budget, I’m hoping to spend less than 2k but would begrudgingly go as high as 5. So clearly I have no idea about construction which is why I’ve found a local company with an Austrian owner who say they can build it but have some questions before they can quote.

One of the questions was “Where the wooden frame meets the inside and outside cladding there will be a sound bridge – is that a problem?” which gives me hope that they are up to the task.

My guess is that since the booth is designed to go inside a room, the single leaf wall of the booth is effectively acting as the inner leaf and since it’s not connected to the walls of the room, there is no sound bridge? If that’s the case, should the booth sit some distance away from the walls (I don’t have much space for that).

Regarding the inside cladding, John has already answered that one (no cladding on the inside, just fabric on pine frames). Does the fabric need to be that special, acoustically neutral variety that I have seen advertised or will any fabric work?

Wiring
As shown in my layout diagram (sort of), the signal cables will run up the wall behind the desk, across the roof and down to a penetration about 30cm in from the top right corner of the window wall of the booth. Is an XLR chassis connector what’s needed here to go through the drywall?

Regarding the power penetration, I’m thinking of locating that diagonally opposite, in the bottom left corner. If I specify a vapour sealed electrical box, will that suffice or is there a higher mass / special audio version I should use?

I could then run power up through the base trap on that side to the lights in the roof and mount the light switch on the front of the base trap?

Power could also be routed to the outlet below the mic inputs like in Johns’ drawing but I am worried about it’s proximity to the signal cables (< 2’). Obviously it’s not a problem since John has done it that way but I am wondering if there is anything special going on behind the box to prevent interference? Is the box something you need to make or is it something you can buy online (what is it called)?

Presumably I would then plug a power board into the outlet to power my headphone amp (which I would also like to mount on the base trap for easy access) and the iPad.

My construction knowledge is surpassed only by my electrical knowledge :lol: Is there anything I need to do for grounding? I read the posts about star grounding but I’m guessing (hoping) that applies more to full studio wiring. Ideally I would like to simply plug in an extension cord to power the booth. Can it be that simple?

If anyone has any suggestions for a better way to do the wiring I would love to hear them.


HVAC
John mentioned that the ventilation ducts were optional which is great since I don’t have room for them. Would I need to put a fan inside the booth to push the “jam out of the jar” or would that happen naturally given the room is not hermetically sealed. I’m guessing I will need to turn on a fan inside the booth as well as opening the door. The room itself is air conditioned.

STC - Door & windows
Correct me if I’m wrong, but it seems the STC rating for the booth will be determined by the density of the drywall sheets used on the outside, provided the door and windows have the same STC or higher? Should I then simply choose the highest density drywall available here for maximum isolation?

For quotation purposes, without yet knowing the drywall density, if I specify 10+6mm for the larger window and 10+8mm for the smaller window will that get me pretty close? (acoustic PVB if available).

If doors (single or double leaf) “should have at least two full perimeter seals”, why does the one in the .swf appear to only have one? Is it because it’s one of those $5000 beauties I can’t afford?

I suspect it may be cheaper for me to have a solid core door but I would prefer the openness of glass. Again, without knowing the drywall density, would 30mm laminated glass and 125kg solid core be a reasonable guesstimate for quotation purposes? (assuming they are properly sealed and the frames/threshold are filled with putty on the glass option)

Floor
Please confirm that I do not need to put a floor in the booth because it is going on tiles laid directly on the slab. I plan to put half an exercise mat in there to make extended periods of standing more comfortable.

The tiles in my room are flat, but I was wondering if I should put a strip layer of rubber (5mm?) under the walls to fill any air gaps created by the grout lines between the tiles and to help compensate for any unevenness in the floor? (photo attached)
floor tiles.jpg
Monitor
The monitor that is visible in my diagram will sit outside the window of the booth and allow the video to be viewed during audio recording (like in my photos of our current setup). I envisage installation on a swinging arm that is attached to the drywall. That may mean a third penetration though, depending on the depth of the screws required. How bad is that? Should I try to come up with an alternative mounting method (perhaps extend the window sill and sit the monitor on top of that?)

WiFi
Do you know if wifi will penetrate the booth? I want to use an iPad connected to my local Wifi network to control my DAW (logicX) during recording.

Storage on roof
Any idea of how much weight I could put up on the roof? I’d like to store our film equipment up there (< 150kg).

Thank you for taking the time to read my post, any assistance would be greatly appreciated! :yahoo:

Jason
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Re: Vocal Booth Design

Post by Soundman2020 »

One of the questions was “Where the wooden frame meets the inside and outside cladding there will be a sound bridge – is that a problem?” which gives me hope that they are up to the task.
That does, indeed, sound hopeful.
the single leaf wall of the booth is effectively acting as the inner leaf and since it’s not connected to the walls of the room, there is no sound bridge?
Assuming that you really do built is just a single leaf, with sheathing on only one side of the studs / joists, then yes, that would be fine.... for the two sides of the boot that are close to existing wall! but for the other two sides, you do need to complete the second leaf, to fully enclose the booth. That second leaf can contact only the existing walls: it cannot touch the new inner-leaf walls.
If that’s the case, should the booth sit some distance away from the walls (I don’t have much space for that).
As long as you have about 4" (10cm) air gap, that should be fine. That's the distance between the surface of your existing wall and the surface of the sheathing on your new inner-leaf wall, not considering the studs or insulation: that doesn't count.
Regarding the inside cladding, John has already answered that one (no cladding on the inside, just fabric on pine frames).
:thu:
Does the fabric need to be that special, acoustically neutral variety that I have seen advertised or will any fabric work?
Any fabfri will work, as long as it is "breathable". In other words, if you place a piece over your mouth and nose, you can breath through it normally, without difficulty. There can be an increase in the air resistance, yes, but not a huge increase so that it makes breathing significantly harder.
Is an XLR chassis connector what’s needed here to go through the drywall?
Do it like this:
Conduit-isolation.png
Conduit-isolation-2.png
Conduit-isolation-3.png
It's just normal electrical conduit (PVC) bent to shape, with a short cut-out section in the middle. maybe an inch long, wrapped with flexible soft rubber Seal all the penetrations with caulk, and after you pull the wiring through, push insulation down each end of the conduit and seal the end with more caulk.
Regarding the power penetration, I’m thinking of locating that diagonally opposite, in the bottom left corner. If I specify a vapour sealed electrical box, will that suffice or is there a higher mass / special audio version I should use?
Same as above.
My construction knowledge is surpassed only by my electrical knowledge :lol: Is there anything I need to do for grounding? I read the posts about star grounding but I’m guessing (hoping) that applies more to full studio wiring. Ideally I would like to simply plug in an extension cord to power the booth. Can it be that simple?
For what you are doing, yes, that's basically all you need to do, provided that that solution would be allowable by your local electrical code. You'll have to cut the plug off so you can push the cable through the conduit, then attach a new plug once that is done.
John mentioned that the ventilation ducts were optional which is great since I don’t have room for them.
Depends how much time you plan top spend in there! if it's just a couple of minutes per day, then that's fine. But if you will be in there for several hours per day, then it is NOT an option! You would have to do that. You can't be inside a small booth like that without any air...
I’m guessing I will need to turn on a fan inside the booth as well as opening the door.
If the door is open, then you don't have an isolation booth.... :) You only get isolation with the door closed.
Correct me if I’m wrong, but it seems the STC rating for the booth will be determined by the density of the drywall sheets used on the outside,
... as well as the size of the air gap between the inner leaf and the outer leaf...
Should I then simply choose the highest density drywall available here for maximum isolation?
It's the surface density that matters. How much each square meter of your wall weighs.
If doors (single or double leaf) “should have at least two full perimeter seals”, why does the one in the .swf appear to only have one? Is it because it’s one of those $5000 beauties I can’t afford?
How much isolation do you need, in decibels? That's the key.
I suspect it may be cheaper for me to have a solid core door but I would prefer the openness of glass. Again, without knowing the drywall density, would 30mm laminated glass and 125kg solid core be a reasonable guesstimate for quotation purposes?
Sam as above: "How much isolation do you need, in decibels? "
Please confirm that I do not need to put a floor in the booth
Confirmed! :) No floor is necessary. You'll be fine with the mat. Just make sure that the walls of the booth are sealed to the floor tiles, using caulk.
The tiles in my room are flat, but I was wondering if I should put a strip layer of rubber (5mm?) under the walls to fill any air gaps created by the grout lines between the tiles and to help compensate for any unevenness in the floor?
For that type of unevenness, caulk is the best answer. You can use normal bathroom caulk: the type the never goes hard, and remains soft and rubbery even after it is fully cured.
envisage installation on a swinging arm that is attached to the drywall. That may mean a third penetration though, depending on the depth of the screws required. How bad is that?
Run all your signal cables through one single conduit, as I showed above.. Make it big.
Do you know if wifi will penetrate the booth?
No problem.

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Re: Vocal Booth Design

Post by Dixie »

Hi Stuart, thank you so much for your reply. I can't believe you even did drawings! I will order a decibel meter and do some more homework before reporting back. Thanks again for taking the time to respond, I really appreciate it.
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Re: Vocal Booth Design

Post by Martha Bern »

Hi! Have you figured out, which vocal booth design is the best in terms of functionality? The thing is that a friend of mine is crazy about music and he has a band of his own called "T-Stars". He's made up his mind to build a vocal booth to hold rehearsals there and I'd really wish to help him with the best design. Thanks in advance for your recommendations, guys!
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Re: Vocal Booth Design

Post by Soundman2020 »

Martha Bern wrote:Hi! Have you figured out, which vocal booth design is the best in terms of functionality? The thing is that a friend of mine is crazy about music and he has a band of his own called "T-Stars". He's made up his mind to build a vocal booth to hold rehearsals there and I'd really wish to help him with the best design. Thanks in advance for your recommendations, guys!
Your friend seems to be sadly mistaken if he plans to hold rehearsals of an entire band inside a vocal booth! Vocal booths are usually big enough for one person to stand in.

Also, please explain what you mean by "best in terms of functionality". A vocal booth is very simple in concept: A small room, or "booth", with a door. The functionality is that you open the door, go inside, close it, sing, open the door again, and exit. I'm not sure how you would improve on that functionality. So did you have a point or were you just spamming the forum? Curiously, you chose a thread that the poster himself marked as an error... Maybe you just selected it, hoping to go unnoticed, as spammers often do?

Considering that you posted four such meaningless comments on four different, unrelated threads in the space of six minutes, then the next day posted a spam link to your spam company, I'm guessing that you are a spammer! :) Bye...

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Re: Vocal Booth Design

Post by lakecarson »

Hi everyone, I'm so glad I stumbled across this forum. What a vast amount of knowledge. This being my first post please forgive me if I go about posting or asking anything in a wrong manner here. I'm moving my bedroom studio to my basement which is opening quite a bit of room for me. It's roughly about 11' W x 18' L x 7' H. I have a vocal/isolated booth roughed in at about 4'x6'. The basement is a finished room, drywall on the walls and ceiling. Now I built the booth off a 8" thick brick wall and the remaining 3 walls are 2x4's filled with roxul and then resilient channel, 2 sheets of 5/8 drywall on the outside and inside, and a solid core door. Now the heating/cooling duct for the whole room runs directly over the vocal booth and is now outside the booth. I have access to the duct work from the other room/ceiling which is not finished. Now my first question is can I just tap that duct with a Tee seeing that it's running right over the vocal booth for Heat and Ac? And will I or won't I need a exhaust fan of some kind? The window glass, is there a standard thickness for each glass? What would you recommend? And the angle of the glass, how is that determined? Do you angle both sides? And running a snake into the booth. What would be the best way for doing that? Thanks so very much...
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Re: Vocal Booth Design

Post by Soundman2020 »

Hi there "lakecarson". Welcome! :)
This being my first post please forgive me if I go about posting or asking anything in a wrong manner here.
It would be a good idea to start your own thread, about your specific studio build, and keep all of your posts about that together in the same thread. That way, it's easy to keep track of everything relating to it.
It's roughly about 11' W x 18' L x 7' H.
That's a reasonable size space for a control room, not so much if you want more than one room in there: and the ceiling is very low. Is that the measurement from the floor to the bottom of the ceiling? Any chance you can take out the ceiling drywall, to get more height?
I have a vocal/isolated booth roughed in at about 4'x6'.
Try to avoid dimensions that are directly related mathematically: Twice the length is equal to three times the width (2x6=12, 3x4=12). That would create the situation where certain resonances inside the room would reinforce each other at certain frequencies- Not a good thing for a studio!
Now I built the booth off a 8" thick brick wall
Are you saying that you directly attached the booth to one of the outer-leaf walls of the house, such that one of the interior walls of the booth is that brick wall? Are you aware that you will not be able to get high isolation like this?
Now the heating/cooling duct for the whole room runs directly over the vocal booth and is now outside the booth.
From what you describe, technically the duct is not outside the booth: it is in between the inner-leaf and outer-leaf, meaning that it is not isolated. Noise from your booth will get into the duct, and vice versa.
Now my first question is can I just tap that duct with a Tee seeing that it's running right over the vocal booth for Heat and Ac?
Assuming that the duct in question was already supplying air to your basement, then yes... with caveats! But if that duct was NOT supplying your basement, then no. For example, if it was supplying your living room, or a bedroom, or some other room, then tapping of air for the booth would reduce the airflow to that other room (or rooms), unbalancing the design of the HVAC system. There would be insufficient flow to the other rooms.

Also, even if that duct is the one that supplies the basement, you still can't just tap into it directly: you need a silencer box in between the duct and the room. If not, then noise form the booth will get directly into the HVAC system, and noise form the HVAC system will get into the room, and into your mics, messing up all of your recordings.
And will I or won't I need a exhaust fan of some kind?
That depends on a whole bunch of things, but the main one is something called "static pressure". If the path that the air would take though the registers that lead into and out of your booth would substantially increase the static pressure for the duct that is supplying it, then yes, you would need a fan: in your case, you would need an in-line fan at some point, either on the supply duct into the room, or the return duct leaving the room. In either case, it would have to go on the far side of the relevant silencer box: wither before the supply silencer, or after the return silencer. If not, then the fan noise would get into the room, the mics, etc. You would need to calculate the characteristics of the fan, in terms of flow rate, flow speed, and static pressure, to ensure that it provides the correct conditions to do the job.
The window glass, is there a standard thickness for each glass?
No. The thickness needs to be calculated for each individual case. It needs to have at least the same surface density as the leaf that it is in. So the glass on the inner-leaf of your wall would need to match the density of the inner-leaf, and the other glass would need to match the density of the outer leaf.
And the angle of the glass, how is that determined? Do you angle both sides?
That one is simple! 1) The angle is 90°. 2) You do not angle either side! :) Despite what you see in photos of "high-end" studios, and even in some misleading text books (as well as an infinite number of YouTube videos about "How I built my world-class studio for seventeen dollars and twenty three cents... :) ), it is an absolute myth that you need to angle your glass for acoustic reasons. You MIGHT need to angle it for visual reasons: if you expect that you'll have lighting issues that prevent you from seeing through it, or some type of glare. But there's no acoustic need at all to do that.

Let me explain: people think that by angling the glass, it prevents sound reflections from getting into the mic. Garbage! All that happens is that the reflection comes form a different point on the glass, but they still get there. And second, angling the glass REDUCES the total isolation between the rooms, because isolation depends on the size of the air gap between the glass panes, and by angling them, you make the gap smaller, which reduces isolation (technically, it drives up the MSM resonant frequency, so the air cavity will resonate at a higher frequency than would have been the case of the glass were not angled, thus implying greatly reduced isolation.

Here's a graphic that illustrates these two issues:
angled-glass-myth-doesnt-work--rbdg-com--.jpg
It's pretty clear, and self-explanatory.

There's one other issue that isn't shown on the image, but still matters: Since most studio mics are cardiod, supercardiod, or even figure-8, they are insensitive to the reflections in any case: for a vocal booth the treatment that is at the rear of the mic matters a whole lot less than the treatment in front of the mic: what's most important, is the treatment on the wall that the mic is pointing towards, not so much the one that it is pointing away from...

In other words, if you want maximum isolation, then don't angle your glass. If you think that you might have light glare issues, then put the lighting in differently, so that it does not create glare conditions on the glass.
And running a snake into the booth. What would be the best way for doing that?
Assuming you want maximum isolation, you would need to run it through a conduit that has a small isolation break in the middle to decouple the two ends, wrap the gap with some type of flexible rubber, then plug both ends with insulation and caulk. However, for a typical home studio, it is probably enough to just run the snake through reinforced "boxes" in the two leaves of the wall, but NOT straight across the gap: in other words, the cable goes through one leaf and immediately curves until it is parallel to the wall surface. Then it runs along several feet, bends the other way, and goes through the second leaf.


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