Do Acoustic Panels Actually Work?

by Thesis Music December 30, 2022

You see acoustic panels everywhere. In movie theaters, auditoriums and stadiums, and in recording studios. You probably even see them in your office (if you're still commuting, that is.)

You even know these places will spend 10s to 100s of thousands of dollars treating their spaces for optimal audio.

But you still have the question - do acoustic panels actually work?

Of course they do - but let's dig in to why they work.

Absorbing the waves

An acoustic panel's purpose is to absorb sound waves and reduce the level of reflected noise in a room or space. They are commonly used in environments where controlling the level of sound is important.

They are an effective way to reduce the level of noise and improve the acoustics of a space.

What is sound?

To understand how acoustic panels work, we need to first understand the basic physics of sound. Sound is a type of energy that travels through the air in the form of vibrations or waves. When these waves hit a solid surface, they can be absorbed, reflected, or transmitted through the surface.

Sound Reflections

Sound that is reflected is commonly referred to as "echo" or "reverb". This is dependent on how much of the sound frequency was reflected, and how well the sound frequency was reflected. A sound wave that is efficiently reflected will sound similar to the original sound, just at a lower volume - this is an echo.

Sound that has parts of it's frequency absorbed will reflect back as a muffled version of itself - this is called reverb.

Surface Transmission

Waves can be transmitted through the surfaces as well. A great example of this is an acoustic guitar.

Acoustic guitars are designed to have the vibrations of the strings transmitted through the hollow wood of the guitar. This leads the sounds to be amplified, and produce a richness to the sound.

Sound Absorption

Sound waves can also be absorbed. You can think of sound absorption material like a plinko board with varying levels of sticks.

The more plinko sticks there are, the harder it is for the plinko disc to drop straight down. Instead, it bounces off of each plinko stick, and ultimately ends up somewhere other than the expected destination.

Depending on the material, you can have a plinko board with so many sticks that the disc never reaches the bottom - instead, it gets stuck. That's similar to how sound absorption works.

Acoustic Panel Effectiveness

So now that we understand what happens to sound, we can now better understand how acoustic panels work.

There are many different types of acoustic panels available, each designed for specific applications and environments. Some are made from dense materials like fiberglass or mineral wool, while others are made from softer materials like foam or fabric. The type of panel you choose will depend on your specific needs and the characteristics of the space you are trying to treat.

To determine whether or not acoustic panels are right for your space, it's important to consider the following factors:

Frequency spectrum: Different types of acoustic panels are more effective at absorbing specific frequencies. For example, some panels are designed to absorb low frequencies (like bass), while others are better at absorbing high frequencies (like treble).
Reverberation time: The reverberation time of a space is a measure of how long it takes for sound to decay after it is produced. In general, the shorter the reverberation time, the better the acoustics of a space. Acoustic panels can help reduce the reverberation time in a space, making it sound more "dead" or "dry."
Absorption coefficient: The absorption coefficient of an acoustic panel is a measure of its ability to absorb sound. A panel with a high absorption coefficient will be more effective at reducing noise than a panel with a low absorption coefficient.

In summary, acoustic panels are an effective way to reduce the level of noise and improve the acoustics of a space. They work by absorbing sound waves and converting them into small amounts of heat. To choose the right acoustic panels for your space, it's important to consider the frequency spectrum, reverberation time, and absorption coefficient of the panels.