Studio Design Part 1

Murfreesboro Rock School is getting ready to settle into its new space and we are beginning to design the layout of the recording studio. We are having a ton of fun and decided to share with you the process as we go.

The most important thing to consider when designing a recording studio is the acoustics. Having a control room that sounds good is very important. If the low frequencies in the room are not balanced or if there are to many reflections bouncing around you can not make a good mix.

I am going to try and keep things as simple as I can, if you have any questions or would like for me to explain things in more depth, do not hesitate to email me I would love to help.


Okay, so to begin with, the control room is 12' X 12' X 8' (WXLXH) and mainly concrete walls (a rough start...)

Humans can hear frequencies ranging from 20Hz (really low notes like a subwoofer may play) all the way up to 20,000Hz (really high frequencies like the squeal of a TV). Each frequency has a wavelength, which is how long (length) that particular sound wave is.

Notice that 94Hz is 12 feet long. That means that 94Hz is going to bounce back and forth in the room perfectly allowing it to sound louder and last longer. This is a big problem for us since our walls are 12 feet apart. The way the walls interact together also causes other frequencies to be problems. Without doing all the math, in our control room we have problems at 141Hz, 282Hz, and 414Hz. Since each frequency is a note, we know there are going to be a few notes that are louder and longer than the rest.


Okay, so lets talk about what we can do to fix these low frequency problems. There are two techniques that can help solve these problems: Bass Traps and Diffusers.

Bass Traps are very dense pieces of insulation typically housed inside a wooden frame.

Now we are on a budget just like you might be, and one bass trap can cost between $300 and $800 so we are going DIY. We have priced the woods, insulation, and other materials to make a state of the art bass trap and have managed to do it for only $40 per Bass Trap! We will post pictures once we start making them.

Okay, so once we build our bass traps we have to know where to put them. Low frequencies easily travel through walls, even using the wall to amplify itself, making corners a prime location for low frequency build up. We are going to put our bass traps in the corners of our rooms. The larger panels on the wall with the window are 2'X4' and the smaller panels on the other side of the room are 2'X2'.

These Bass Traps absorb lots of low frequencies, helping eliminate some of our problems. Now we are going to look at the other way we can reduce low frequencies. Diffusers break sound up. Normally when a sound wave hits a solid wall it bounces straight back but if you put a diffuser on the wall, it scatters the sound in many different directions. This weakens the power of any individual part of the wave. Here is what a professionally made diffuser may look like.

As you can probably guess, these are also very expensive. What you are looking at above could have easily cost $6,000. So as you can also probably guess, Rock School is going DIY and building them ourselves. Pictures and updates to come.

Now where we put our diffusers is also very important. If they are too close to where the engineer is going to sit they can reflect the sound right at the engineer and make mixing very difficult. This makes the back wall of a control room a pretty ideal place for diffusers.

Okay, so our diffusers and bass traps should do a pretty good job of taking care of our low frequency problems. Now we need to deal with the higher frequencies. Higher frequencies do not fill up a room like low frequencies do, instead the shoot in very specific directions through out the room. You can think of a low frequency like throwing a bucket of water while a high frequency is like a water gun.

When higher frequencies reflect off a wall and then bounce over to the recording engineer, there is a small time delay between the signal directly from the speaker and from the reflected signal. This time delay causes music to sound muddy and even make it difficult to work with certain frequencies. We need to keep sound from bouncing off the walls and ceiling and then at the engineer. In order to do that we are going to add foam at the places where sound could bounce back to the engineer. The foam will absorb the sound when it strikes the wall, keeping it from bouncing back. 

Reflections from the left

reflections from the right

Reflections from the ceiling

Now the only other thing that we need to deal with are the reflections that go to the back of the room and then bounce back to the engineer. Putting too much foam in a room can make it sound dark or dry, which makes mixing difficult. Since the back wall is much further away than the side walls we are going to use diffusers designed to scatter higher frequencies, you can see them in the rendering below as the smaller diffusers to the sides of the low frequency diffusers.

So, here is the final product.

We are starting construction soon so please check back as we will be posting a new blog every few days with updates and how to build all these acoustic products. Thanks!~