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Installed Dynamat in my Xterra

I installed some speakers I got for Christmas and Dynamat on my doors while they were off. I did not take any pictures on how to take the door panels off and install speakers, being that I have a .pdf of the Crutchfield Master Sheet I can post here as soon as I can figure out how.

I purchased a Dynamat Extreme Trunk kit from Amazon for about $80.00 and it came with 5 sheets that measured 18” x 32”. I was always under the presumption that one was supposed to completely cover the door opening with it. According to Dynamat, this is wrong. The Dynamat Xtreme is not a deadening or blocking material, but it is a dampening material whose purpose is to add mass to the metal panel in order to dampen the vibrations being produced. They recommend around 30% coverage to dampen effectively. They also stated that their Dynaliner line of products is what is used to cover the inner door skin openings to block noise from entering.
So, with this in mind, I removed my door panels and went to work. This was significantly more involved than just swapping speakers because not only did I have to remove the door panel, I needed to remove the vapor barrier. Before removing the vapor barrier, I needed to remove the panel mounts that were screwed into the inner door skin.
You can see the two metal support struts used to secure the arm rest in that photo. They are the metal pieces immediately left of the wiring harness. If just installing pictures, this is as far as you need to go in regards to disassembly.

In addition to being used to dampen the vibrations of the metal, it can also “reflect” sound and keep it where it is supposed to be. To do this, all I did was put some on the outer door skin right behind the speaker opening, shown in the pictures below.
You can also notice in those pictures that I applied Dynamat heavily around the speaker openings, being that this location will be a strong source of vibrations.
Below are shots of the doors after I applied the Dynamat to the rest of the inner and outer door skin. I followed Dynamat’s recommendation and tapped the metal with the butt of a screwdriver and where I could hear a “tinny” sound I would apply a small patch of it. After tapping around and hearing nothing but solid “thuds,” I put the speakers in and the door panel back on. Also, Nissan was kind enough to have already installed a dampener from the factory. It is the pinkish thing attached to the outer door skin in the pictures below.
Some items to note:
1. They recommend using a roller to press in the Dynamat to get as much solid contact with the metal as possible. I just used the butt end of a screwdriver to do it. It did get the job done effectively, but it did mess up the printed on logos and mar the finish on the aluminum. This will never been seen again, so I did not care about that.
2. You will NEED to wear some kind of gloves to do this job, as that aluminum will cut you long and deep. I have a few pair of HyFlex gloves around and they seemed to protect my hand well while still allowing good dexterity.
3. The material used is butyl and it is EXTREMELY sticky. If you let it fold back on itself, it may not come undone.
4. Work with small pieces. It makes the handling of the material easier (see Note 3.)
5. Make sure it is CLEAN. I used body solvent because I had a bottle of it, but alcohol or acetone will work good as well.
Now, as far as its performance, I would do it again. The doors sound like a Lexus when I close them and I have a 2 - 2.5 dbA reduction in my cabin, as measured by a smartphone app that was “calibrated” by a certified meter at work. It sound small, but remember that a 3bdA reduction is perceived as roughly half the noise. The low drone of road noise is reduced, but now I notice the wind noise more and more road noise from the rear hatch area. There is NO echo or reverberation from behind my speakers or in my door. I have upgraded door speakers in the past and always had a tinny sound. With this stuff in there, all I here is the music and the bass is tight and not even remotely muddy. When I was a teenager, having the whole town here your music was “cool.” I am pushing 40 and am no longer cool, so both my neighbors and I appreciate that the Dynamat keeps the music in my X and I can hear significantly less music with the door shut.
After using only half of the material for the doors, I have some left to use on the rear hatch and possibly the rear wheel wells, so stay tuned.
Looks Good, Back in my high school days i helped a buddy cover his Honda with Dynamat, it was a long and tedious project and i think added 200lbs to his car. It made the HUGE difference in the sound and ambient noise in his car.