Hey everyone! It’s Duy here, ready to drop some knowledge about car sound damping (aka sound deadening). With the release of our new sound damping materials, Stinger Silencer, now would be a good time to educate our readers about everything sound damping.
What is Sound Damping
Sound damping materials are used to improve the sound quality of your audio experience in your vehicle by adding materials to a vehicle to reduce unwanted noise, squeaks, rattles, and vibrations.
Imagine your car's sheet metal panels like drumheads. When they're thumped by bumps on the road or vibrations from the engine, they naturally resonate and transmit that noise into the vehicle cabin.
(Above) Stinger Silencer with an 80 mil aluminum layer & butyl rubber mat.
Adding sound damping will let you hear your audio system much more clearly, and it is integral for audiophiles when installing an aftermarket sound system.
How Does Sound Damping Work
The first layer (facing layer) in sound damping material is a reflective layer acting as a barrier to sound waves, like aluminum. This thin layer typically sits on top of a butyl rubber mat. While aluminum doesn't directly absorb sound waves, it can reflect some of the higher frequencies back into the damping layer which can improve the overall effectiveness at reducing those higher-pitched noises.
Sound damping materials that incorporate aluminum foil can also reflect radiant heat, helping to keep the car's interior cooler, especially in hot climates.
(Above) Stinger Silencer sound damping effects
The second layer acts as an absorption layer, like butyl rubber mats. These dense mats are applied directly onto the sheet metal. They act like vibration dampeners, absorbing the energy from the tremors before they can travel through the metal and into the vehicle’s interior. This dampening effect significantly reduces the overall noise level by stopping the panels from acting like noisy drumheads.
The absorbed vibration energy isn't destroyed, but rather converted into a tiny amount of heat within the butyl rubber mat. This heat dissipates harmlessly, further reducing the chance of it being transmitted as noise.
How Much Sound Damping to Apply
We recommend covering at least 60% of your vehicle in sound damping material for a 6-10 dB reduction in noise. A coverage of 25% is the minimum amount for any noticeable impact, resulting in a reduction of 3-5 dB. A 100% coverage rate can reduce noise by up to 15 dB.
(Above) Sound Damping (yellow line) can reduce untreated noise (red line) by up to 15 dB.
Where to Apply Sound Damping
The best places to apply sound damping material depend on what type of noise you're trying to reduce. The two main sources of noise are from the road and engine.
(Above) Prioritize damping locations based on your goal of enhancing car audio or reducing road noise.
To reduce road noise, look to apply sound damping materials on the doors, floorboards, and wheel wells.
- Doors: A significant amount of road noise enters through the car doors. Applying sound damping material to the inner metal skin of the doors will significantly reduce this noise. Door car speakers can also cause vibrations and sound damping mats can help minimize these effects.
- Floorboards: Road noise from the tires and undercarriage travels up through the floorboards. Applying sound damping material to the floorboards, including the trunk floor, can greatly reduce this noise intrusion.
- Wheel wells: Some sound damping materials can be applied to the inner wheel wells to further reduce road noise coming up from the tires.
(Above) Stinger Silencer sound damping applied to a door with a Stinger Audio Component Speaker.
To reduce engine noise, the firewall and hood are areas that make sense.
- Firewall: Engine noise primarily enters the cabin through the firewall, the panel separating the engine compartment from the passenger cabin. Applying sound damping material to the firewall can significantly reduce engine noise.
- Hood: While less common, applying sound damping material to the underside of the hood can also help to dampen engine noise, especially high-pitched tones.
Other areas on a vehicle that can be sound dampened are the trunk and roof.
- Trunk: Sound damping the trunk lid and floor can improve sound quality for subwoofers and can also reduce road noise coming from the rear of the car.
- Roof: Sound damping the roof can help to reduce wind and road noise from above.
Other Benefits of Sound Damping
While most car owners use sound damping materials to enhance the clarity of their audio sound system, those seeking a quieter and more comfortable drive can also utilize sound damping materials.
A quieter cabin can make for a more relaxing and enjoyable driving experience, especially on long trips. This can be especially beneficial for people who spend a lot of time in their vehicles, such as commuters, salespeople, chauffeurs, ride-hailing drivers, or delivery drivers.
(Above) A quieter ride can lead to a more comfortable experience for your customers
In some cases, sound damping materials can also increase vehicle resale value. Cars with higher quality sound systems and quieter interiors tend to have a higher resale value. So, if you are planning on selling your car in the future, sound damping may be a worthwhile investment.
How to Install Car Sound Damping Materials
Car sound damping can be a DIY project, but it can be time-consuming and challenging, especially for beginners. If you are not comfortable working with car interiors, then hiring a car audio professional is recommended. Professional installers will have the experience and expertise to properly apply the sound deadening materials throughout the car for maximum effect.
However, if you have some experience or like the challenge of any DIY project, here are some tips and steps to guide you on your install.
General Tips
When cutting sheets of material, it is best to use a piece of cardboard or wood to place under the material when cutting.
If the outside temperature is at least 60°F (15°C), you can leave the material in the sun to warm the material up for best adhesion. If below 60°F, heat up the material with a heat gun on the low setting.
Recommended Tools:
- RK Roller or Hand Roller
- Utility Knife
- Gloves
- Heat Gun or Sun
- Planning the Installation
Determine which parts of the vehicle you want to dampen. The recommended coverage is anything with a metal surface.
- Removing Panels and Cleaning the Surface
Using a plastic pry tool, remove panels and upholstery to get down to the bare metal.
(Above) Stripping door panels to the metal surface.
When working on door panel area remove any plastic barrier behind the door panels. When working on the floor, remove any carpet and or insulation to get to bare metal.
Confirm the surface you plan on installing the material is free of dirt and grease. For cleaning the surface, use products marked “degreaser”. We recommend using denatured alcohol.
Wipe the surface down using denatured alcohol.
- Installing the Sound Damping Materials
When cutting sound damping material, it is recommended to use gloves and a utility knife. Use caution when handling material because of sharp edges.
Cut sound damping sheets to desired size using a template or freehand.
Remove the paper backing on the damping material to expose the butyl adhesive. For larger sheets, remove part of the paper and slowly work your way across the metal panel and remove the backing.
Place the sheet as flat as possible, avoiding excessive air pockets. Using your hands, slowly flatten out the remainder of the sheet. Be careful around the edges.
Using the hand roller, roll out any remaining air pockets. If any stubborn air pockets remain, use the utility knife to make a small relief cut, and roll out that area.
Car sound damping reduces road noise, engine rumble, and overall cabin noise, making your commutes much more pleasant and allowing you to hear clearly all the high and low notes of your audio sound system. We hope this guide was of some use to you. From all of us at Stinger, safe travels and happy listening!