John Sayers' Recording Studio Design Forum Archive

Hi!

New here and hope I can get some good advice!

Just started working as an assistant in a studio and one of my tasks is to treat the room that is eventually becoming studio B.
The room will be used for pre-prods, simple mixing, recording of synths, vocals and other simple recordings that can be done in this room.
I'll just get right to it and give you the details:

The room is rectangular and the measurements are L= 3,45 meters, W= 2,80 meters & H= 2,40 meters.
On one of the short-walls there are four window-frames. Two pair of same sized window frames. One pair is quite small (maybe 20x80 cm) and the other pair is much larger. About 80x80 cm. Don't have the measurement of how deep they are (sorry) Probably about 20-30 cm. On the opposite wall is the door, also wood and it flushes with the door.
I'll post some pictures as well so you'll see how it looks like.

Every surface is wooden panel. And there is a sofa a bit behind the mixing-chair. We hope it will work as a bass-trap.

The budget is as small as possible. But we have a roof at about 1200 dollars. +/- .. ..

So grouping my questions:
How can we make the room sound as good as possible with the information I have given you?

What material should we use and where should we put it?

Other useful things that I probably haven't mentioned?

Grtz,
Jon
Aspiring studio-dude.

Hi Jon, and Welcome to the forum!

The room is rectangular and the measurements are L= 3,45 meters, W= 2,80 meters & H= 2,40 meters.

Ouch! That's pretty small! The recommended minimum size for a critical listening room, is 20m2. It is possible to have a good room in less space, but the smaller the room is, the more treatment it needs...

And there is a sofa a bit behind the mixing-chair. We hope it will work as a bass-trap.

It might help a bit, but it's made of the wrong materials an is in the wrong place to be a good bass trap.

What material should we use and where should we put it?

Before you think about materials and treatment, you first need to get the geometry and setup correct.

First, the speakers: They need to be set up so that the rear corner is 10cm from the front wall, and the acoustic axis is 79 cm from the side walls (so they will be 122 cm apart from each other). They also need to be set up at a height of 125 cm above the floor. For all of those measurements, I'm talking about the location of the acoustic axis of the speakers, not the top, bottom, or side of the speaker box. You'll need better speaker stand, too. Those are very flimsy. Speaker stands need to be massively heavy.

Next, the mix position: Set up the chair on the room center-line, such that your ears will both be about 130 cm from the front wall when you are mixing normally. Now set up something vertically (such as a mic stand), about 30 cm behind your head, also on the room center-line. Carefully rotate each of the speakers so they are both pointing perfectly at that vertical pole.

That's the correct geometry for your room. Set up the desk in front of the chair, so that it is in a comfortable position.

Now the treatment: Take down that shelf on the left wall, and remove the speaker in the right front corner. Those are both creating a symmetry problem, and they are both in locations where you will need treatment.

Now buy some sheets of "Owens Corning OC-703" insulation, 10cm thick. Cut some of it into triangles that measure 50cm along the two shorter sides, and stack those up in the front corners of the room, from floor to ceiling. Yes, the one on the left will partly cover the window, but you have no choice. Make a simple frame to cover that, and put some very thin plastic film on the inside of the frame (facing the insulation), and decorative fabric on the outside (facing the room). The plastic should be about the same thickness as a newspaper, roughly.

Do the same for the left rear corner of the room, where you have the mic setup at present. You should really have another one in the other rear corner, but the door is in the way...

OK, those are your "superchunk" style bass traps. They aren't big enough, but it is impossible to make them bigger in that room: they would take up too much space.

Now make set up two small panels of OC-703 behind the speakers, up against the front wall, about 80cm wide and 100 cm high. (Yes, they will cover the windows too: but once again, you have no choice). Center those between the speakers and the wall.

Next, make two wooden frames, each one 15cm deep, 1m wide and 2m high, and put a piece of OC-703 inside each frame. Cover the frames with decorative fabric, and hang the frames on the side walls, at the first reflection points.

Finally, cover the rest of the rear wall completely with more OC-703, two layers deep (20cm): You can put it in frames if you want, and cover it with fabric to hide it.

That's about all you can do with that room. It won't be fantastic, but it will be a LOT better than it is now!


- Stuart -

Hi again!
Thank you for a really helpful reply!

We have done some changes since I made the post. We have turned the studio around so that the previous right wall is now the front wall.
We also removed the couch and put in a wall-to-wall carpet.
How much does that effect the room treatment and what should we do now that we have turned it? Is it better to switch back maybe?
We also painted it black!

I'll post some pictures on how it looks now.

The measurements are still the same: L= 3,45 meters, W= 2,80 meters & H= 2,40 meters.
And the walls and roof are still of wooden panels.

Best regards,
Jon Olav

We have done some changes since I made the post. We have turned the studio around so that the previous right wall is now the front wall.

Not such a good idea! In a small room, the speakers should always be aimed down the longest axis, never the short axis. You need the space between your head and the back wall to be as large as possible.

We also removed the couch and put in a wall-to-wall carpet.

Another bad idea! 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), 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 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. Control rooms need to have neutral acoustics. Take a look at ITU BS.1116-2 to get an idea of how tight a control room needs to be kept, acoustically. It is flat impossible to achieve that with carpet.

Secondly, it is on the floor, which means it destroys the reflections from the floor that your brain relies on to build an "acoustic picture" of the room. All your life, wherever you go, your ears are exactly the same height above the floor, and your brain is very, very accustomed to figuring out the acoustic signature of the room based on the reflections it hears from the floor. If you sit down, your brain recognizes that, and adjusts it's "image" of the room accordingly. It does not use the ceiling or the walls for that, because the distance from your ears to the walls and ceiling changes all the time, many times per second as you walk around, so the "signature" is not constant or consistent. Ceilings are different heights, and when you walk outdoors, there is no ceiling at all! But there is still a floor, and it is still the same distance from your ears as every other floor.

If you have carpet on the floor, your brain no longer has any reflections to use for this.

Finally, it messes up your psycho-acoustic perception of the speaker locations, as well as your ability to accurately determine directionality, so you'll never get an accurate sense of the real sound-stage, and never have an accurate stereo image. Carpet is pretty good at destroying spatial perception.

So forget the carpet. You'll find it really hard to have a good acoustic setup in a room with thick carpet on the floor. Take a look at some photos of high-end pro studios: how many of those have thick carpet on the floor? There's a reason for that...

How much does that effect the room treatment and what should we do now that we have turned it? Is it better to switch back maybe?

Yes, I would definitely turn it back to face the correct way, and also take out the carpet.

We also painted it black!

No problem with that! Paint color does not affect acoustics at all.... It looks rather good like that, actually!


- Stuart -