I just wanted to share my experience with sound deadening the G. I love my G during spirited driving but for longer treks, the road noise really got on to me (not to mention how awful the "Premium" stereo sounds). My former car was a Lexus GS300 so I got a bit spoiled with the hushed ride. I set forth to do something about it, but there were so many products on the market, I didn't know where to start. I found this website that has what seems to be an objective comparison of all the products out there.

http://www.sounddeadenershowdown.com/

I went with the Damplifier line by Second Skin Audio based on this review and some other forums on the net. ( http://www.secondskinaudio.com/cgi-bin/index.cgi?p=hm )

I started with the easiest accessed point, which were the wheelwells. The easiest approach was from the outside so I started with removing the wheels, removing the plastic liner, and cleaning the area w/ 99% alcohol. I layed down one layer of Damplifier, then covered it with the thick Spectrum Sludge. Once it dried I put the plastic and wheels back on.

 

Next, I turned to the interior and pulled up the carpet in the driver and passenger side. There are some how-to's that are online that you can refer to for removal of the trim pieces. It was pretty simple. I started with one layer of the Damplifier, covering as high up on the firewall as I could reach. Next, I put down a think layer of Spectrum Sludge (make sure you let it dry completely before you put anything on top or put the carpet back.... I learned the hard way ). The final layer was a closed cell foam called Overkill that acted as a sound absorber (not as effective as open cell foam, but it was water proof). I put all the carpet and trim back once everything was completely dry.

 

The next step I took was putting a layer of Damplifier and Spectrum Sludge in the trunk and trunk lid (sorry, forgot to take pics).

Then I turned to the rear seat that was pretty easy to remove. I layed down a layer of Damplifier, Spectrum Sludge, and Overkill under the rear seat (no pics either, sorry). I left the rear side panels and rear deck alone because my brother could never get those pieces to fit just right after he took his apart.

The final part were the doors. I was a bit apprehensive at first, but found some great instructions on how to remove the panels. Once things were removed, I put some Damplifier on both the outside sheetmetal and also the inner panels. Then I put down some Overkill foam adheared w/ 3M 90 adhesive spray. I didn't put any sludge in the doors because I didn't have time to leave the door in pieces to let it dry. Sorry for the crappy pics.. only had my camera phone handy.

 

Did it make a difference?

 

So far I have only deadened the doors (3 layers of Rammat on outer skin, 1 on inner skin, closed cell on door cards) and trunk (2 layers of Rammat on tub and lid). I have not had the time to get to the rest of the car. I can certainly tell a difference in midbass output. Also the trunk is dead mostly rattle free.

I am really interested in your results for reducing ambient sound. I am guessing the wheel wells made the biggest difference?

Reviews man! We need reviews!

 

Several hours and a few hundred dollars later, I"m finally done. I did this over a few days so it didnt' overwhelm me. The final results? Well, I took my camera and recorded a before and after ride in the same conditions. Unfortunately, they sounded the same.

From a subject perspective, I have to admit, I wasn't quite sure if I made that much of a difference. The problem was, I did each part in phases and I drove the car a bit in between each step.

I really noticed the change when I took my car in for an oil change and picked up an '05 G35 sedan as a day loaner. MY GOSH, THAT CAR WAS SOOOO LOUD!! I had gotten so use to my car that when I drove that car, it felt like a Dodge Neon. That's when I really appreciated all the work I had done.

So in conclusion, you can never make your sports car ride like a Lexus. If you set out to do this, you will be sorely disappointed (or extremely broke because you would have to go overboard on sound damping material). If you want to make your stock Bose stereo sound louder and better... if you want to cut out a significant amount of roadnoise from our super wide 19's... if you want to use your Bluetooth without having to shout at the top of your voice (still have to speak loud and clear though)... if you want that satisfying thud of closing a solid door... if you have realistic expectations from sound deadening, then by all means do it. I am very glad I did it. If you don't have the time or money to do it right, then I would not do it at all.

If I had to choose the most cost effective areas to work on, it would definitely start with doors, then the wheelwells. These were the places I felt I heard the most difference.

Post up if you have any questions or need clarification. Let me know your sound deadening experience and if it was similiar to mine.

 

Here's some links to the resources I used to get this project done.

http://forums.freshalloy.com/ubbthre...1#Post67759010

http://digitalwheelz.com/diy/index.html

http://www.thegsquad.org/DIYS/Rear%2...%20removal.jpg

Also, a special thanks to Ant at Second Skin Audio. He was a great help when I was in the planning stages of all this. He didn't just try to sell me the most expensive stuff, but he pointed me to the materials that would benefit me the most in my application. A true stand-up businessman.

 

Anthony is a good guy. I personally do business with Rick McCallum, but would switch to SS if Raam ever goes away.

You have inspired me to tackle the wheel wells next. Thanks for the review!

 

My pleasure. I've learned so much from these forums... I just wanted to contribute what I could.

 

Great info and thanks for the contribution. I wish you had pictures of the trunk because I just got finished doing mine and have noticed that my back window and my rear shelf are now the culprits for rattles

 

rear shelf sucks needs gasketing foam underneath it as per the TSB also needs a towel or something underneath it too, I will be attacking my rear deck on Friday when I pull out my back reclining seats (sedan) to change out my subs. I plan on dampening the underside of the rear deck, gasketing foam where the TSB suggests and then putting some fabric between the rear shelf and whatever is underneath it. If I bang on it right now it squeaks and gives a couple of inches, which sucks ***

 

wow great writeup! i love the sound of our cars, but the ambient road noise kills me. i will definetly consider doing this.

 

Please take some photos and document this method and how well it works