Radioflyer97's How-To Post #13: Sound Deadener/Acoustic Insulation installation. (C5)

First, let’s cover the difference in various Passive Acoustics commonly used in Car Audio.

Mat Deadener – (example: Dynamat) A foil backed rubber-like mat that adheres to a by glue surface adding mass to the panel and thus reducing vibrations caused by movement in the car itself.

Liquid Deadener – (example Edead V3) A Liquid paint-like material that adheres to the surface performing the same function as mat deadener. Liquid deadener is more difficult to apply, but allows a varying thickness of layers for bigger problem areas.

Acoustic Foam – (example: Second Skin’s Luxury Liner) Open or closed cell foam that is specifically designed to inhibit the transmission of sound waves from outside the car . These are usually between ¼” and 3/8” thick. These are extremely effective against exhaust noise.

When I bought my car, it came with a set of Borla Stingers which were cool, but I wanted My car to have the option of being quiet when I wanted….even at the dreaded 2000 rpm drone speed. The areas that I found to be most critical were as follows:

a) Wall immediately behind seats – this area has virtually NO acoustic insulation and being at a nearly perpendicular angle to the sound waves coming out of the exhaust is a panel that’s prone to transmit exhaust noise. Deadening and foam here are essential
b) Cargo Tubs – These are essentially big drums that need deadening. The whole cargo area could really use deadening.
c) Doors – The doors consist of 3 large panels that are prone to vibration. I put the most amount of deadening here mostly because that’s where the most critical speakers were (front midrange/woofers)

For my installation, I chose to use Dynamat extreme, Second Skin Damplifier pro, and for acoustic foam I used Second Skin’s “Overkill Pro” 3/8” closed-cell foam.


The Wall behind the seats:

http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0911.jpg

If you want to install amps, processor brains, HD/sat radio or other goodies behind the seats, this is when you’ll want to mount the anchor boards

Here’s my ERA G320 brain test-mounted on the anchor board with the Acoustic foam under it. Ran a layer of overkill foam from the bottom here to the back of the cargo area.
http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0946.jpg


Here’s the stripped cargo area:
http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0887.jpg

And dynamat installed
http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0909.jpg

http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0908.jpg

http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0910.jpg


The Doors:

Dynamat on the plastic interior part of the door panel itself:
http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0907.jpg

Inner and outer door panels deadened:
http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0906.jpg

http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0912.jpg

Acoustic Foam (top layer)
http://i27.photobucket.com/albums/c200/radioflyer1986/CIMG0966.jpg


A rough comparison of before and after using my EPIC-150’s SPL meter showed that at highway cruising speed noise levels dropped between 5-7 dB after the insulation. Most of the noise was due to very low frequency vibrations the microphone was picking up.

Clean Job!

Is there Room For The Matt And The Form?

Looks Like A Winter Project, It's On My List.

I Wish There Was Something I Could Do For The Wind Noise At Higher Speeds On The Convertible Top, At The Sides. :eek: :eek: