Just finished installing some sound deadening material in my C7. I'm very pleased with the results. Install below...

Notes: I used B-Quiet Ultimate for the deadener and Luxury Liner Pro for the absorption layer. The B-quiet came in a roll and was really easy to work with. The LLpro was nice because it is a Mass Loaded Vinyl with a closed cell foam bonded to it. It does an amazing job however it is a little thick and will not form to shapes easily. Also, you need some amazing glue if you want to mount it to anything without squeezing into place.

I did the entire cabin below the windows minus the seating area floor. I pulled the carpet up there a little and there didn't seem to be enough space for the LLpro. I could have pulled the seats and carpet for B-quiet alone, but it didn't seem worth it as the floor panel is pretty sturdy and needs more absorption than damping.

To save some space and link other's efforts, I used THIS THREAD. for reference dismantling the interior.
Make your life WAY easier and GET PLASTIC TRIM TOOLS if you haven't already.

Anyway, onto the pics:

Subwoofer from 2LT/3LT. The enclosure is vented to the opposite side from the woofer. It seems like pretty light weight material so in an effort to get some better bass response I added some deadening. I am VERY pleased with the results be doing so.



Up-close on the vent



Rear Tub with the BQ



The panel installed over the electronics.



LLpro behind the seats



LLpro covering the rear. I still hear the exhaust just fine when I get on it, but in tour just cruising it is barely there. (I have NPP fyi) Great result for my long trips.



BQ and LLpro on the rear trim over the wheel wells. The white material is the GM attempt to absorb sound throughout the car.



Another sheet of LLpro over the wheel wells with a cut out for the targa mount







I did the doors as well with BQ on the inner and outer skin. I used the factory installed white sound absorbing material as a general template to cut the LLpro for best fit within the panel. It will be impossible to get 100% coverage and still get the panel back on so I'd say coverage is at about 60%. I forgot to snap some pics, but trust me the results are worth it.

GM did a great job with the C7, and I understand the effort to save weight, but mine is DD and road tripper. I want a quiet ride on LA's crappy roads (non-runflats are next) and I want to enjoy my tunes. All in all, I'd say I added approximately 40 pounds of material to my car which I am perfectly ok with. The BOSE system sounds great now. It's not a sound competition car by any means, but for the investment the results are phenomenal.

 

Awesome.
Really? The pieces like that work too? I've never used deadening
material before but i always thought a full cover was necessary.
Wow if what you used is 40lbs, i could imagine what the full cover weighs in at. Too much im sure.
Great thread by the way. Cool mod and great pics.
Im an audiophile and have built and still use tube gear for my listening enjoyment and am wondering what changes that made, did it help with the highs? I'm not a big fan of bose except for the 901's and i have the bose system in my c5 vert as well thats why im curious because i may end up doing this to mine as well. I'ts very road noisy as hell, too much for my liking. are you still using the stock deck?
Also i am interested in the remaining materials, price depending
of course. Shoot me a pm about the logistics. Thanks.

 

So, with the deadening material, the goal is to add mass and break up the resonance within the car's material itself. Studies have shown that 50% coverage focused on the center of the vibrating panel will deaden an appropriate amount. Also, it must have a full, bonded contact the surface to have any effect what-so-ever, so going over curves makes life difficult. Check out THIS WEBSITE for some great explanations and tutorials on the topic. Now, having said that, you DO want as close to full coverage as possible on the acoustic barrier materials (the luxury liner pro in my case).

The major weight in the install was the Luxury Liner. That stuff is heavy, about 11lbs per 9sq ft "sheet". The B-Quiet (the metal stuff) is actually really light.

In the C7 I kept everything stock. The deadening on the sub enclosure/vent really helped clarify the bass from the rear. I also put a ton of deadener on the panels behind the tweeters and subs in the door. Altogether these helped move the stock system up to the next level. As I've said, it isn't a competition system, but the improvement is noticeable and the effort was definitely worth it.

Before this car I had a '04 coupe, which I gutted and added sound deadening and completely changed out the Bose gear for Focal K2 Power gear and a Kenwood HU. That was an AMAZING improvement and really renewed the car and brought the car up to speed with today's standard tech.

 

Brilliant post! Thank you.

Can you tell us the square footage of the B-Quiet deadener you used and also the LLPro?

What type of glue did you use on the vertical surfaces to stick the LLPro on?

 

Rattletrap Xtreme 25' sq

 

Very nice work and excellent write up.
I'm not quite following what you did with the sub woofer enclosure.

Please elaborate
Tks