How Can You Soundproof Your Car

The soundproofing of a vehicle (and any listening space matter) is an essential stage for who is looking for a sound reproduction. There are many ways to soundproof a car: tar products, acoustic wool (natural or synthetic), convoluted foam, wood and even concrete for extremists sound.

Before addressing the practical side, see what we have to fight against and in what ways.

When a sound wave strikes a surface it is divided into three distinct parts, each will have a different way of bringing its propagation lot of disadvantages.

 1.A part of the sound energy is returned

These reflected waves will then be perceived by the listener with a delay time and added to the main signal, which will have the effect of degrading sound clarity by adding that there we call glare.

We distinguish here three absorbents families:

– The fibrous products: made from glass, rock, wood or cotton.

– Cellular products: open cell foams.

– Textiles: carpet, rugs or felt.


The sound through this material is gradually lose energy by effect of friction with varying efficiency depending on the thickness of absorbent, if the other side the wave is a hard surface (such as sheet metal) then part of that wave will take the same path in reverse of new energy.

It is obvious that this kind of treatment has very little effect on longer wavelengths such as serious (I assure you right here I would not push the subject further on the lengths waves!) but on the other hand the efficiency increases with increasing frequency.

One last thing to consider, each absorbing its properties is more likely to work on a certain frequency range. By multiplying layers of different materials to increase your chances of you then cover a wider frequency spectrum amortized.

2. Another part is absorbed by the surface material in question, and has the effect to resonate therein.

Indeed each material reacts to a frequency of its own, for simplicity we take as an example the plate of a door but it works for anything, not just in the car audio. Once the sheet that is in the presence of its resonant frequency, will the capture and absorb.

This is where the tar, in addition to being neutral (no resonance frequency as the resin) it stiffens the sheet preventing resonated to its original frequency. You will find the tar in different forms:

– Brushing or spatula: primary tar building, blaxon, etc …

– Roll plate or sticker: sometimes with a layer of aluminum or foam, single chamt.

– Heating: or roll roofing membrane plate.

Here there are no more secret it is tarring best! At equal thickness all these products is the same result.

 3. And finally the third part goes to the other side of the material encountered.


And yes even all doors closed there is always a bit of its passing either one side or the other.

Here I speak to most those who make SPL to counter these energy leaks and thus pressure. Materials that return the greater part of the sound energy are hard materials, such as successive layers of wood, concrete or the floor tiles.

For standard installations redo the door panels (or in part) in medium and carpeted trunk is quite beneficial and sufficient. Last technical detail (after I plug you peace and we go to practice) it is acoustic bridge that can ruin all your soundproofing efforts. The connections of a wall to another, plated pedestals against a hard surface or the contact between the bowl of an hp (or screws) and its support can transmit vibrations to the rest.

Flexible joints (rock wool strips, strips of foam, silicone seals) can improve the situation, but cannot eliminate the inevitable links.

As part of a complete soundproofing you have to get your car scrutinized, I suggest you work with small parts and then go back as soon as we quickly made it overflow.

Start with the holes in the body that are real small enclosures resonances, you will find along the underbody on seatbelts amounts in the rear wings and certainly in the trunk. If you wish the then fill until you drop glass or rock wool, and then close with foam.

The floor of the passenger compartment and the trunk should be tarred quantity to remove as much as possible road noise that it goes very well with the music, take the opportunity to spend all your wiring and nothing prevents you to top up absorbent in addition to the original one. It is rare that the roof in resonance and I advise not to touch it, or even better if you make it reverberating doing, combined with an absorbent floor it will report the sound image which in most cases is breast height.

The doors are full of items just waiting to vibrate: sheet metal, plastic parts, clips, linkages, etc…

We’ll have to remove all these noise sources without blocking the moving parts that the passage we certainly need fat. You can thread the metal rods in foam or other, making joints with carpet scraps on the screws and all that is in direct contact with the sheet (think acoustic bridges!)


Here there are brief with no rules. Then go to tarring I suggest you roll the stickers found in DIY stores, it’s more expensive but clean and easy to install. They have to (+/-) 3 mm thickness and 3 layers is really the minimum “union” (especially behind the hp) and remember there are three metal surfaces to be treated. If you feel the need to absorb the materials have to find it on the inside of the plate that supports the lining, because do not forget that on the other side of rain runoff do and do not clog holes evacuations.

Small return to technical on this subject through the sound absorbing products is seen slowing its speed, so virtually the door become larger which will allow your hp down a little deeper into the grave.

You can also pave the insides of the plastic of the cockpit on the old cars that we often tend to “tweet” word! Or use a felt layer sandwiched between two medium boards for the trunk, in addition to treatment earlier course.

Finally you will understand there is no miraculous recipe, soundproofing is often made of odds and ends cleverly set up. And very often with ordinary materials and inexpensive hardest being familiar with the operation of the sound waves and their effects well counter. To end on a humorous touch I would say for good soundproofing, we must “think” like a wave!!!!

About the Author Leroy Simmons

My name is Leroy L.Simmons. I create this blog as the way to find out my excitement and also a way to remember my father. I always love writing, I embarked on this adventure of the blog, to tell you all that I want to share about my hobby, my dream of auto, truck and journey. At MRVEHICLE.NET, I hope to tell you great stories and especially to answer some questions you might ask. And there are also many interesting and up-to-date stories of drivers on their journey everywhere in the world.

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