Learn Sound Control

Why controlling sound is so important

Acoustic absorption plays a vital role in shaping how we hear and experience sound in any space—whether it's a recording studio, restaurant, office, or home. Without treatment, sound waves bounce off hard surfaces, creating long and unpleasant reverberation times. This can blur detail, mask the original sound source, and make communication or listening uncomfortable. Read More

When sound reflects unevenly around a room, certain frequencies become exaggerated while others are diminished—creating distortion, or what's commonly known as peaks and troughs. This effect can make music sound muddy, conversations hard to follow, and overall acoustics feel harsh or fatiguing.

By strategically placing acoustic panels within a space, excess reflections are absorbed, and the sound becomes clearer, more balanced, and easier on the ears.

High-performance materials like polyester fibre and rock wool offer excellent acoustic absorption at a low cost. While originally designed for use inside walls of industrial or high sound-pressure environments, these materials are also effective when used externally to reduce echo and improve acoustic clarity in everyday spaces.

How sound absorption actually works

To absorb sound efficiently without taking up unnecessary space, a material must be porous—packed with tiny air pockets. As a sound wave travels through this labyrinth of fibres or cells, it repeatedly transitions from air to solid and back again. Each transition creates friction, converting a small portion of the wave’s energy into heat (imperceptibly low). This gradual loss of energy is called dissipation. Read More

Why Porous Materials Excel

Fibrous batts (fibreglass, mineral rock wool, polyester) and open‑cell foams are ideal because their structure maximises these air‑to‑solid interfaces, making them highly effective broadband absorbers.

Thickness, Density and Gas-Flow Resistivity

Thickness determines how low in the frequency spectrum absorption remains effective. Thicker absorbers tackle lower frequencies.
Density (or gas‑flow resistivity) must balance thickness:
- Thicker panels → lower density
- Thinner panels → higher density
If density is too high for a given thickness, the panel starts reflecting rather than absorbing.

The Power of an Air Gap

Leaving an air gap behind the absorber—ideally the same depth as the absorber itself—boosts low‑frequency performance. Why? Particle velocity peaks at roughly one‑quarter of a wavelength from a rigid surface (your wall). Placing porous material where air is moving fastest maximises friction and, therefore, absorption. Beyond a certain gap, benefits taper off (diminishing returns).

Tackling Deep Bass

Sub‑bass wavelengths are often too long for practical porous absorbers. Instead, resonant (membrane) absorbers—such as limp‑mass vinyl or diaphragmatic panels—target these frequencies by vibrating in sympathy with the wave and dissipating its energy.

By combining the right material, thickness, density, and placement, you create a controlled acoustic environment that keeps reflections in check and lets the original sound shine through.

Diffusion and absorption

While diffusion and absorption are technically opposites, they are often used together to achieve balanced acoustics. Absorption works by removing sound energy from a space, helping to create a quieter, more controlled environment. Diffusion, on the other hand, is designed to scatter sound energy rather than eliminate it—preserving a room’s liveliness while avoiding harsh echoes or focused reflections. Read More

Diffusive elements are typically made from timber or other hard materials and shaped according to precise mathematical formulas. These structures help create pleasant, natural-sounding reflections, which are especially useful in spaces like live rooms or recording studios where a rich, tonal ambience is desired. In contrast, absorption is preferred in critical listening environments such as mixing rooms, where the goal is to minimize the influence of the room on what is heard through the speakers.

While there are standard practices for using absorption and diffusion in different types of rooms, the final approach often depends on personal preference and the unique character of the space.

Treatment Vs Proofing

Sound treatment and soundproofing are often confused, but they serve very different purposes. Treatment focuses on improving the acoustic quality within a room—reducing echo and creating a more controlled listening environment. Soundproofing, on the other hand, is all about preventing sound from entering or leaving a space. It deals with sound isolation, not sound control. Read More

Soundproofing is a complex process and depends heavily on the specifics of a building’s structure. Porous materials like acoustic panels are excellent at absorbing sound within a room, but they’re poor insulators. Sound can still pass through them easily, so they’re not effective at stopping noise from travelling between rooms. What they can do is reduce reverberation, which in turn lowers the overall sound energy that might leak out.

Our panels are designed for absorption—not isolation. They help create better sound inside a room but won’t block noise from passing through walls or floors. True soundproofing requires heavy, dense materials like mass-loaded vinyl (MLV), bricks, concrete, or specialised construction techniques. It's most effective when integrated during the building phase and is generally difficult (and expensive) to add afterward.

While we don’t provide soundproofing products or installation, we do offer a consulting service to help guide you through the most effective strategies for your space.

Densities and gas flow resistivity

There is often some confusion in the audio community relating to densities and different absorption materials. The most common misunderstanding is that density is mostly relevant as it is titled on most insulation products, when in fact a more translatable unit of measurement is 'gas flow resistivity’. Read More

Two materials for example, glass wool and rock wool, with the same densities will have slightly different absorption performances as the core material is different. Gas flow resistivity is measured in rayl/m2 or Pa.s/m2 and is the resistance provided by the material that impedes the flow of sound energy. There are a number of forums on Gearspace.com about this topic.

When sound energy transfers from one medium (air) to another (insulation material), there is usually an impedance difference at the interface where they meet. What this means is that when the sound wave reaches the surface of the material, if the material is too dense or too torturous a sound path due to the complexity of the fibres with the core structure; then the impedance that the sound wave encounters is too high, and most of the sound energy cannot penetrate and is reflected. If the impedance encountered is too low, then the sound wave will travel through the material without losing much energy (i.e. not absorbed).

There is an optimum balance where the impedance encountered is low enough to allow the sound energy to enter the material easily, but high enough to absorb it. Unfortunately this is not a single number, as it is entirely dependent on frequency.

10,000Hz = oscillating air particle 10,000 x per second
100Hz = oscillating air particles 100 x per second

High frequency sound waves lose energy much quicker than low frequencies as they are moving much faster at each time losing energy as they interact with the material. So for example, a low density porous material will absorb more high frequencies than low frequencies. If you increase the density, it will start absorbing more low frequencies also. If you keep increasing the density, sound energy will begin to be reflected and this will usually start occurring at the higher end of the frequency spectrum.

Absorption coefficients, Noise Reduction Coefficients (NRC) and R-values

Absorption coefficients are often found on charts for displaying the performance of sound performance on a given insulation. Read More

Each coefficient represents the fraction of sound energy that is either being absorbed or transmitted; i.e. the fraction of sound energy that is not reflected and is usually given in 1/1 octave band frequencies (i.e. 250Hz, 500Hz, 1000Hz etc.)

Noise Reduction Coefficient (NRC) is the average of absorption coefficients over 250-2000Hz and is a commonly used single number rating. It is used to more easily determine the products over all performance.

R-values are often misinterpreted as being related to sound, but is a thermal performance rating and not associated with acoustics (they are designed to go in walls after all).

Polyester vs other insulation absorbers

We use Polyester insulation in all of our products for a number of reasons. One standout factor that Polyester has over other insulation materials is that it's 100% allergy free. The batts contain no breathable fibers and poses no potential health risks, whereas others do. Read More

Polyester is also extrememly durable and will last a lifetime. The material is made from recycled plastic bottles minimising its environmental impact and is relatively lightweight. Polyester insulation is one of the most recent inventions in the building industy and can be used for a number of applications. Modern acoustic treatment products are almost all made from Polyester due to its flexibility and ability to be coloured, shaped and moulded to any size without the need of covering.

The mis-marketed achrosity, ‘foam’

Often when people treat a room, they do so with low density, inexpensive foam. Why? Because it’s cheap to make and lightweight, it is easily sent around the world from large manufacturers. Read More

Foam has unfortunately flooded the market for quite some time and should really not be considered an effective absorber. Companies often market them as ‘studio grade foam’ or ‘sound proofing foam’ which is falsely advertised. These products target only the high end of the frequency spectrum, unaffecting the mid and lows which is necessary for critical listening spaces. Therefore, thicker and denser materials such as insulation are far more suited.