Noise has been shown to decrease the quality of our living spaces and add stress to our
lives. That’s why the residential soundproofing market has exploded over the past few
decades. As the market grew, more products were introduced, with soundproofing foam
being one of the leading solutions. You’ve likely seen acoustic foam used in
residential, commercial, or industrial settings, and it also has a role to play in
Soundproof foam is a useful tool in your toolkit to create a more comfortable car
environment. The sound absorbing and decoupling done by foam products plays a key role
in decibel reduction and improving your car’s acoustics, often making them a necessary
supplement to sound deadening and sound blocking material.
We spend a lot of time in our vehicles, so It should be a comfortable space. Soundproof
foam will reduce interior noise and echoes to give you the best environment for your car
audio and your day-to-day life.
Avoid Mistakes. Know What Foam Will Do…
And What It Won't
Don’t buy a piece of foam, attach it somewhere in your car, and expect your car to be any
quieter. Foam will not “block” noise like mass loaded vinyl.
It also will not work as a vibration damper for metal like our butyl rubber mat or liquid sound deadener.
Foam will, however, absorb airborne sound waves. The frequency and total amount of sound
absorbed depends on the foam.
||Damplifier Pro, Spectrum
||Stops noise from structural vibrations by deadening the metal
||Luxury Liner Pro
||Fused foam and MLV act as a heat and noise barrier
||Closed cell foam decouples hard surfaces
||Open cell foam absorbs sound waves
Foam Products Absorb
Think of soundproof foam as a sponge, but instead of absorbing water it absorbs noise.
Unlike a hard metal surface which will reflect sound waves, the porous foam surface allows
sound waves to penetrate it. Once inside, the wave reverberates around the interior of the
foam until it runs out of energy or it exits. Even when sound waves exit prior to
dissipating, they will have less energy than when they entered. This energy reduction is why
thicker foams tend to have a higher sound absorption coefficients (we’ll get to it) –
there’s more space for sound waves to get lost in there.
What Type of Foam Makes a Good Sound Absorber?
If you’re looking to absorb sound, you’re looking for an open cell foam. Open cell foam excels
at absorbing mid-to-high frequency sound waves and is used in everything from gymnasiums to
There are a ton of foam products out there, but most of them are not much use in your vehicle.
We’ll get back to that, but to understand how foams are evaluated – you need to be able to
read a chart.
This chart shows you how effective the product is at absorbing different types of sound.
The y-axis ranges from 0 to 1 and shows the percentage of sound absorbed. 1 = 100%
The x-axis shows a range of hertz, indicating the sound wave’s frequency. In the
soundproofing industry, an STC rating measures effectiveness from a standard range of 125
Hz to 4000 Hz – so many tests cover those frequencies.
Each colored line represents a different thickness level at which the foam was tested. A
thicker foam will absorb more sound.
Success on this chart means absorbing as much sound as possible, while keeping the foam as
thin as possible. It’s an important measure of quality, but you need more than that to be good
enough to put in a vehicle.
Foam in Vehicles: You Need 3 Things
For a foam to make the cut to go in a Second Skin vehicle, it needs to do three things:
- Designed for wear and tear
- Resist the elements
- Enhance sound quality
Our foam products go through rigorous testing to ensure they can take a beating. These foams
aren’t going on a wall to spend the rest of their lives 30 feet in the air. You’re installing
them in a modern miracle of design and technology that is constantly exposed to heat, wind and
rain, while traveling at sometimes lethal speeds on all sorts of terrain. This foam needs to
be able to take a punch. But what foam do you need?
Open Cell versus Closed Cell Foam
If you're comparing open cell versus closed cell foam,
open cell foam is a less sturdy product and will absorb water, so it needs a hydrophobic treatment to
prepare the foam for vehicle use. Do not put foam that isn't water resistant in your
vehicle, especially not the door panels! The trapped moisture creates the potential
to grow black mold, which can literally kill you. Closed cell foam
is denser and more rigid. It’s not very good at absorbing most sound waves, although it will do
a little bit to stop low frequency sounds, such as engine and road noise.
||Type of Foam
||Touch & Feel
||Open Cell Foam
||soft and flexible
||mid-to-high frequency noise
||flame resistant thermal insulator
||Closed Cell Foam
||dense and rigid
||Minimal; some low frequency noise
Our Mega Zorbe product is a ½” thick melamine foam
that we’ve treated to be more durable and hydrophobic. It’s great for thermal insulation,
absorbs an impressive amount of noise, and comes with the option to include an adhesive backing
for easy application.
Our OverKill line of products come in 1/8” and 3/8” thicknesses and are
excellent decouplers. OverKill’s primary uses are to squeeze it between plastic panels to
stop rattles and to combine it with a mass loaded vinyl (like Luxury Liner) to create a
noise barrier on top of your sound deadening. We have customers who swear they’ve shaved a
couple decibels just by shoving OverKill behind cupholders.
A common use for both Mega Zorbe and OverKill is to install it inside the door panel as an
easy way to improve the acoustics of the door. Mega Zorbe is more effective, as it’ll absorb a
lot of the back waves, but OverKill will help too – similar to putting a carpet in an empty
Need More Guidance? Second Skin Can Help!
If you’re looking for more help or advice on your project, give us a call. We’ll help you
choose the right combination of products to get the best results. Put our years of experience
to work and simplify your project!