Acoustic Treatment 101: Guide for Home Recording Studios

By Tim Wilson •  Updated: 03/12/23 •  7 min read

Soundwaves travel and strike walls in predictable ways. However, how the sound reflects once they hit the wall or a hard surface is different. Controlling how reflected sound moves is the key to making your home studio sound good. There is no 100 percent perfect sounding room, but educating yourself and making key decisions about your recording space can significantly improve it.

Acoustic treatment involves applying solutions that will help absorb or diffuse sound to improve how your recording studio will sound. The three key areas of a home studio acoustic treatment are low-frequency control, control of early reflections, and control of sound decay.

Common Acoustical Problems

Regardless of the space you set up your home recording studio, you will face some common acoustic problems. These include comb filtering, room modes, flutter echo, and excessive decay time.

Comb Filtering

This is when the sound produced is combined with its reflection within a short interval. Comb filtering sounds like a jet plane landing. Some common situations you’ll encounter comb filtering include;

To eliminate comb filtering, pay attention when combining signals, be careful when using multiple mics on a single source, and deal with reflections of your speakers on walls and other hard surfaces.

Room Modes

These are naturally occurring resonances, also called standing waves. They are caused when sound travels or reflects off various surfaces like two side-by-side walls or between the floor and ceiling. Adding acoustical treatments like bass traps and acoustic panels can reduce the effects of room modes, standing waves, nodes, and anti-nodes.

Flutter Echo

This usually occurs when two parallel surfaces reflect sound between one another, causing a series of echoes. Flutter echoes differ from long-delayed echoes or reverberations because they are multiple echoes that occur in rapid succession. To deal with flutter echo, acoustic panels can absorb or diffuse the flutter echo.

Excessive Decay Time

When you’re in a gym or cathedral, echoes can be heard for several seconds after the source of the sound stops. This is the decay time when a sound wave bounces around without being absorbed or diffused. Long decay times will make it harder to mix cleanly in the room. Acoustic panels are great at diffusing and absorbing long decays.

Solutions to Acoustical Problems

Low-Frequency Control

Bass traps or low-frequency control devices are the most important considerations during acoustic treatment. When the low frequencies are poorly controlled, your mixes might sound muddy (too much bass) or Thin (less bass). The recordings could also have bad resonance or cancellation effects (hollowness). Controlling the low frequencies can smoothen things out.

Bass Traps and acoustic Panels in a Home Recording Studio

Bass Traps and acoustic Panels in a Home Recording Studio

The effective frequency range of loudspeakers or other sound sources should be considered when choosing the best acoustic treatment for low frequencies. Most good low-frequency devices can address a wide range of low-frequency problems. However, they tend to be expensive or take up too much space. Pressure, velocity, and hybrid devices are used for a home recording studio. However, there are a lot of DIY approaches that are also effective.

Early Reflection Control

Controlling early reflections is done mainly using absorption materials. Because the frequency range of reflections is higher, even thinner materials can be effective. This offers you more choices when it comes to aesthetics and home recording finishes. In most recording studios, the common materials used are one of the three “Fs” fiber, fabric, or foam.

For all the above products, the thicker the material, the better it will perform. For higher frequency reflections, the thickness should be 4-6 inches. If you want to absorb more low frequencies, a thickness of 12 inches would be suitable.

Locations to Add Acoustic Treatment

When your studio monitor speakers produce sound, there are three stages in which you’ll perceive it:

  1. Direct sound, which is clean straight from the speakers.
  2. Early reflections are reflections off hard surfaces in a room, such as walls, floors, and desks.
  3. Lastly, You’ll hear a reverberant sound reflecting the original sound interacting heavily within the room.

Critically Acoustic Treatment Zones

The goal of acoustic treatments is to make the direct sound the main focus and reduce reflections and reverberant sounds to a high degree. Below are some locations where acoustic treatments are much more effective.

Apart from corners, sidewalks, and back walls, adding diffusers to large rooms’ ceilings and upper walls will prevent excessive decay. The use of reflection filters around the mic will also help keep your vocal recordings clean by absorbing unwanted noise around the mic.

Tim Wilson