How Room Shape and Materials Affect Recording Quality

Have you ever wondered what the how certain materials in the room might affect the way a recording sounds?

Have you ever thought that the shape of a room might change how the recording sounds?

Both of these, in fact, are huge factors that play in to the end resulting quality of a recording.

Likewise, it is equally important to consider how they will affect your recording and you should take necessary precautions to avoid having a negative effect on your recordings.

Each material found in a room will affect the sound just the same way that the shape of the room can affect the reflections of the sounds. In your resulting recording, you will be able to hear not only the room but also the materials around you.

Today we will discuss the difference between some materials as well as reflection, absorption and diffusion.

Recording Ambience

When recording with microphones we have to remember that we are going to be recording the room ambience as well as the source sound. In other words, this is how the sound reverberates through the room.

The room shape and size as well as how and with what materials the room was built will impact the recording quality of the sound and the level of ambience that is captured by the microphone.

The use of diffusers in a recording room can change the way the sound is captured.

First we are going to talk about size.

How Room Size can Affect Recording Quality

If the room is large and the mic is in the center we will get a large and more reverberated sound. If the room is smaller we will get a tighter, less ambient sound. We can also achieve a similar result by placing the vocalist in a large room but closer to a wall or a corner Shape of the room will depict how many reflections occur after the source sound has ended.

  • Square room: Sound reflections will repeat on top of themselves potentially creating standing waves. These will pose issues when recording.
  • Odd-Sided room: These reflect frequencies clearly and will thus result in a clean and natural sound. Sound waves do not just bounce once, they will reflect multiple times. There is a term known as standing waves. Standing waves cancel out frequencies because of overlap. Odd sided rooms are preferred as they can prevent these cancelations.

How materials shape the recording of sound

Understanding how a room’s construction materials affect the sound of a room is also incredibly important and just as crucial to the shape itself. Materials contribute to how the sound is captured in a room. Wood, glass, cement, foam, carpet and tile will all create and shape bright and dark reflections to varying degrees. There are 3 important qualities that materials in the room possess. Namely they are

  • Reflection = Hard materials like glass and cement cause reflection. Here, most of the sound is reflected in such a way that the reflected sound is nearly as powerful as the source before it hit the reflecting material
  • Absorption = Soft materials like foam and carpeting can cause absorption. Absorption is similar to reflection. The key difference is, however, that most of the power of the source is ‘absorbed’ into the material and little of the original power of the signal is reflected out again.
  • Diffusion = Materials that possess the ability to diffuse will scatter the sounds into very tiny and almost random reflections. This does not deaden the sound that much.

Creating a Good Recording Environment

When it comes time to decide between which type of materials to use or how many walls to put in your studio, it can seem a bit overwhelming.

Too dead of a sound can sound a bit unnatural. In nature, there are reflections but a room with even walls is just an invitation for un-natural reflections.

We need a little bit of reflection to sound natural. Thus, a combination of diffusion and absorption is the most ideal for this reason.