John Sayers' Recording Studio Design Forum Archive

Hi ,

I am a film composer in London UK .

I am about to start building a small 3.6x3metre studio for composing and mixing in my garden . I have planning restrictions re size and have attached a drawing showing what I am permitted . The back wall will not be perpendicular because of the back wall in my garden . ie the room wont be an exact rectangle . I know the room will need accoustic panel treatment after but presume not being equal helps?
Also I can slant the ceiling , is that worth doing ?

I have decided not to have the basin and toilet shown on the drawing and have made the longer dimension another 120 mm so the internal length is 3625 and width 3070 height is 2320 with the possibility of adding another 350 mm to slope the ceiling . The bifold doors on the right will have accoustic glass . I was assuming I would slope the ceiling from the back wall to the doors and place the desk facing the doors .

1.Is it worth doing the ceiling in such a small room?

2. Does having the back wall angled cause issues and should I straighten it ?

3. As the studio is isolated do I need extra soundproofing ( I dont work that loud )

4. SHould the speakers face the back wall or the glass doors ?

5. In a room like this carpet or wooden floor?

6. Should I order the bifold with trickle vents as I have no windows . I will have aircon and just open door from time to time if I need air . Neighbours are far enough away.

Many thanks for any advice

Charlie

With that shape room, the only feasible layout is orienting the room so that it faces to the right side of your page, with the angled wall behind you.

I have decided not to have the basin and toilet shown on the drawing

Very smart move! Yes, definitely.

The bifold doors on the right will have accoustic glass

So it seems that isolation is not a high priority?

with the possibility of adding another 350 mm to slope the ceiling

If you can add another 350mm at one end of the ceiling, then how come you can't add that at BOTH ends of the ceiling, and simply raise the whole thing 350?

1.Is it worth doing the ceiling in such a small room?

Well, you do need a ceiling yes! So it's definitely worth doing a ceiling!!! But NOT worth sloping the ceiling. Just make it as high as you can possibly get it.

2. Does having the back wall angled cause issues and should I straighten it ?

It's probably not an issue. It's not a large angle, it's at the back, and you'll need a ton of treatment back there anyway.

3. As the studio is isolated do I need extra soundproofing ( I dont work that loud )

Only you can answer that question, and you'll need a sound level meter to do it. You need to come up with a number, in decibels, that defines how much isolation you need. "Loud" and "quiet" are relative terms, and subjective. Decibels are measurable.

4. SHould the speakers face the back wall or the glass doors ?

Already answered.

5. In a room like this carpet or wooden floor?

Neither. Just use the concrete slab as your floor. If you don't like the look of concrete, then you could laminate flooring on it. But certainly not carpet!

6. Should I order the bifold with trickle vents as I have no windows .

Not if you want isolation!

I will have aircon and just open door from time to time if I need air

Ummmm.... no. Just nope. That's not a viable plan, and would not work anyway. Air needs a reason to move: there has to be a difference in pressure across the room in order for air to move. If you only have a door on one side, there is no pressure differential, so the air won't move. It will just sit there, inside the room, stagnant and not going anywhere. You need an actual HVAC plan. You might think you don't, but you do. HVAC is a critical part of any studio, even a small one. Look over several similar builds here on the forum to see how to do that. You might think that the main reason why you need it is the lack of oxygen, but that's actually not true. It's the excess CO2 buildup that will kill you in there, long before you run out o oxygen...

Neighbours are far enough away.

Far enough away for what? Far enough away that they won't notice you suffocating in there, with the door closed, lying unconscious on the floor from CO2 poisoning?



- Stuart -

Many thanks Stuart,

All seems sound advice Haha.

Do you mind explaining a couple of things

5.Just use the concrete slab as your floor. why is that better than a more absorbant material ?


6. Should I order the bifold with trickle vents as I have no windows .

I do having planning permission to put an opening rooflight in the ceiling , maybe I should reinstate ? I was worried that might prevent accoustic ceiling treatment and interfere. would it be better to put in a small window on the side for ventilation ?

The bifold doors on the right will have accoustic glass
So it seems that isolation is not a high priority?

They will be double glazed with and extra layer of accoustic glass .Should they be triple glazed then or do you mean there is too much glass in the 1st place. ( Its a design feature to match the kitchen opposite so yes a compromise for isolation but lets in a lot of light.

10.You need an actual HVAC plan. I will investigate but any advice welcome as I am not sure how this works


Thanks

5.Just use the concrete slab as your floor. why is that better than a more absorbant material ?

Concrete is about the best possible floor you can have in a studio: It is hard, rigid, solid, massive, acoustically reflective, etc. Just what you need.

There are several reasons for that, both acoustic and practical. The biggest acoustic reason is that your ears and brain are accustomed to hearing reflections form the floor, and use that as a sort of spatial reference. Wherever you go, throughout your entire adult life, your head is always the same distance form the floor as you walk around, so your brain understands that reflection really well. The distance from your head to the walls and ceiling changes constantly, so your brain isn't as interested in that, but the floor is always there, so enhancing that reflection helps your brain get a sense of the room. The same applies when you are seated: even though chair heights might vary a bit, you'll find that when you are seated your ears are pretty much always about 1.2m above the floor... which is why standard speaker height in studios is 1.2m above the floor!

If you put carpet on the floor, you rob your brain of that reference reflection.

Also, in terms of room acoustics, carpet does the exact opposite of what you need in a small room. Small rooms need a lot of bass trapping (the smaller the room is, the more it needs); they also need some controlled absorption in the mid range on a descending curve (more at low mids, less at high mids), and little to no absorption in the high end. Carpet, however, does the exact opposite: It sucks out all of the high end wonderfully, absorbs some of the mid range randomly on an ascending curve, and does nothing at all to the low end. So not only is it useless, it actually makes things worse. Carpet will make your room sound dull, boomy, muddy, and dry. If you are tracking drums, for example, it will suck out your crash and ride, wreak havoc on the hi-hat and some of the snare, trash the toms, and make the kick sound like a wet cardboard box inside a concrete pipe....

Control rooms need to have neutral acoustics. Take a look at ITU BS.1116-3 to get an idea of how tight a control room needs to be kept, acoustically. It is flat impossible to achieve that with carpet.

There are practical reasons too (concrete wears better, is easier to clean, does not harbor dust, pollen, spores, etc). But the biggie for me, is the acoustic and psyco-acoustic reasoning.

Take a look at photos of high-end studios from all over the world: How many of them have fully carpeted floors? Pretty close to zero...

I do having planning permission to put an opening rooflight in the ceiling , maybe I should reinstate ? I was worried that might prevent accoustic ceiling treatment and interfere. would it be better to put in a small window on the side for ventilation ?

I guess I did not explain this clearly enough: You cannot use operable windows, skylights, doors, vents or anything similar to ventilate a studio, for a simple reason: airtight. Your studio must be airtight if you plan to have good isolation. Because if air can get in or out anywhere, then so can sound (after all, sound is basically just vibrating air..). Unless you specifically and intentionally build something that blocks the sound while allowing air to pass. That "something" is called a silencer box. Here are several examples:

http://www.johnlsayers.com/phpBB2/viewt ... 0&start=45
http://www.johnlsayers.com/phpBB2/viewt ... 9&start=74
http://www.johnlsayers.com/phpBB2/viewt ... 25&start=2
http://www.johnlsayers.com/phpBB2/viewt ... 42&start=5
http://www.johnlsayers.com/phpBB2/viewt ... 61&start=0
http://www.johnlsayers.com/phpBB2/viewt ... 5&start=98
http://www.johnlsayers.com/phpBB2/viewt ... &start=157
http://www.johnlsayers.com/phpBB2/viewt ... =2&t=13821
http://www.johnlsayers.com/phpBB2/viewt ... 8&start=44
http://www.johnlsayers.com/phpBB2/viewt ... 2&start=16

The bifold doors on the right will have accoustic glass

Same issue: If it is bi-fold, it will be very hard to get proper air-tight seals on it. It needs to be sealed completely, around the entire perimeter, such that air cannot get through at all. That's already hard to do on a simple hinged door, even harder on a sliding door, but much, much harder on a bi-fold door.

Also, I'm not sure what you mean by "acoustic glass". Many people and even some unscrupulous companies try to sell ordinary double-glazed units (sometimes called "thermo-panel glass") as "acoustic glass". Those are single units that have two panes of thin glass separated by a thin air gap inside (a few mm). They are NOT acoustic barriers. They only attenuate sound in the mid range and high end, but do very little to block low frequencies, such as drums, bass, keyboards, electric guitars, etc. True acoustic glass is a single thick laminated glass panel, solid all the way through, that is built up from two panes of thick glass with an acoustic PVB inter-layer sandwiched between them. A typical studio window is made from two such laminated glass panels: one goes in the outer leaf wall, the other goes in the inner-leaf wall, and there is a large air gap between them (several inches).

They will be double glazed with and extra layer of accoustic glass

See above..... also, if you have three sheets of glass in there (two in the double-glazed unit, plus an additional pane), then that's even worse! That is now a three-leaf system, which potentially gives even worse isolation than a single-leaf system or a two leaf system, all other factors being equal.

or do you mean there is too much glass in the 1st place.

You can have as much glass as you want, as long as you do it right. Proper laminated acoustic glass is rather expensive, so big windows are expensive. As long as you don't mind spending lots of money on it, there's no problem with having lots of glass, from the point of view of isolation. However, there might be other acoustic reasons why you would not want to do that: If you have glass at a point in the room where there are reflections from your speakers, you'd have to put thick acoustic absorption on that point to make the room usable, and it seems silly to spend a lot of money on glass, then cover it up...

10.You need an actual HVAC plan. I will investigate but any advice welcome as I am not sure how this works

It's fairly simple: you need one duct to bring fresh air into your room and that duct needs to have a silencer on it (see above), as well as one duct to take out the stale air (also with a silencer on it), plus a fan to move the air. The fan can go either on the inlet duct, to "push" air into the room, or it can go on the outlet duct "sucking" air out of the room. You only need one fan: Since the room is sealed air-tight, sucking air out of one duct automatically sucks air in through the other one. The fan and the ducts need to be sized correctly for your room, such that they move the correct volume of air at the correct speed. Normally you want the flow speed to be considerably lower than 300 FPS, and the flow rate to be enough that you replace the entire volume of air in the room at least 6 times per hour (once every ten minutes). In addition to that, you'll need a small mini-split system, that does the actual cooling and dehumidifying.

Look around the forum: There's many examples of rooms similar to yours, built by forum members, and you can see how they dealt with these issues.


- Stuart -

Thanks Stuart ,

I really appreciate the detailed response.

I had an accoustic studio consultant come round today who made pretty much all the same points.
He did however say that as I had some room to play with with the ceiling , it would be worth sloping it to the same degree as the roof ( pic 219b attached )
leaving an equal airgap.

I will look into just having 2 glass panels and one opening glass door instead see section detail 314

the glass is
6.4-16-6.4 Lam Low E Tuff : Standard Argon Gas Filled ie 16 mm gap between two 6.4 panes.

or I have the option of triple glazing ?

If you ever visit west London I had better make sure the floor has remained as the concrete slab or else I think you might have me certified. Actually I might go for a 2mm polished concrete finish made by a spanish company called microcement ( comes in groovy colours)

Thanks Charlie