Saw this in a Maxima forum, seemed pretty helpful so I thought i'd share it here





Alright, boys and girls...as promised here is my $0.02 on the sound deadening/dampening issue. I am disgusted with the volumious responses given in which Dynamat is touted as being the greatest vibrational-stopper ever. WRONG! It's not bad, but there are many better, cheaper alternatives that will give you not as good an effect, but BETTER. I do not claim to be an expert in this category (or any for that matter), but I have done an extensive amount of research on all of these brands and have gained a great deal of information in my studies.


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WHY - We deaden our cars to defeat unwanted vibrations in the trunk, door, rear deck, etc. so that our cars don't sound like $20,000 peices of tin in a windstorm. Some of us do it to kill ambient noise from the road, wind, etc. Lexus inteiors are equipped with piezo-electric devices which actually serve to cancel out the ambient frequencies between 500 - 2000hZ. While we don't have that advantage, there is ALOT we can do to stop it. A well-deadened system will have a much richer bass and midbass sound & feel since the waves will be in our interior, not stuck in the nether known as our interior panels. Another great thing about deadening our cars is that we can reduce the heat inside the cabin since the deadener acts as a resistor against the energy in ambient air.

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DEFINITIONS
There are two types of sound deadening, which are as follows:

MASS LOADING - Involves adding weight to a particular panel of the vehicle to inhibit vibration/rattle. Somewhat effective in defeating ambient soundwaves, great for bass improvement. Pads and liquid deadeners work best for this application.

BARRIER LOADING - Involves adding an acoustical absorber as to absorb sound waves from ambient noise (road, engine, wind, etc.). Great for ambient noise, somewhat effective in improving midbass. Foams work best for this application.

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TYPES

PADS - Butyl Rubber & Asphalt pads such as Dynamat, Damplifier, Roadkill, etc. Need to be applied to metal. Look for a thick pad (>45mils) with a nice heatfoil sheild (>4mils).

FOAMS - Ensolite, rattle pad, overkill, acoustical foam, etc. Can be applied on top of plastics and metal. Works best over an asphalt pad. Look for a closed cell foam.

LIQUID - eDead V3.0, Spectrum, Sludge. Works for both mass and barrier loading. Can be applied on top of plastics and metal. Works well alone or over asphalt pads. Look for a semi-viscous putty/paste. Much easier painted than sprayed.

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BRANDS

Here are a number of various companies whom produce deadeners. Many members have used many different brands. This list is in no particular order. Many of these brands are cheaper because they come factory direct, thereby eliminating the middle-man cost. Click on the brand name to link to their site.


eDead
*Highly affordable solution to deadening

Cascade Audio
*Expensive but worth every penny

Quiet Car
*No reviews available

Stinger Roadkill
*Very expensive, very effective

B-Quiet
*Another good alternative

Raam Mat
*Arguably the best mat available, esp. when layered

Brown Bread
*Good, but better can be found.

Dynamat
*Good, but not worth the price at all.

Fatmat

Peel n' Seal
*Used in the roofing industry. Stinks, doesn't work well.

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SURFACE PREPARATION

As with paints, you too must take measures to ensure proper adhesion of your deadener. A highly regarded practice is to first wipe the area down thoroughly with a degreaser to remove any oils that might lie on the surface. This is to be followed with a second wipe down of acentone to make sure the surface is bone dry. Make sure NOT to cut corners on this step!!!

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APPLICATION

ASPHALT MAT & FOAMS
(1) Using a heatgun, warm the surface of the adhesive side until it begins to tack.
(2) Firmly press your mat into the desired spot.
(3) Thoroughly roll over the mat with a heavy-duty roller. I'd recommend a rubber roller since it will contour a bit better to unlevel planes.
(4) For foams without the benifit of OEM adhesive, I recommed 3M Super 77 Spray Glue.

LIQUIDS
(1) DO NOT SPRAY!!!
(2) Use a quality 2" horse-hair brush and simply paint on.

 

I want to kill my dash rattle eventually, after I'm done with this round of mods. I need to know how to take the dash apart and apply pads to all the clips. or something... ???

 

I think there may be a screw loose in your dash but either way someone just asked a question about this lol

here ya go:

https://www.evolutionm.net/forums/ev...hole-dash.html

 

If folks are truly interested in deadening - what it is, what it does, what it does not do, and how to use it effectively - go to www.sounddeadenershowdown.com and read every page. You'll know more about it than 99% of the people who try discussing the topic.

 

I dynomatted my car.... it cost about 500 bucks... I did the outside part of the inner door pannels... the inside portion, everthing... ran wires through in small portions.. in the front the rear, on the roof and the floor as well as the entire trunk... I honestly dont think it added to much weight to the car all in all.. and as far as road noise goes.... it didnt do ****..... however music wise... it made a HUGE difference.. I have upgraded speakers in the doors.. ( rockford fosgate t3 components in the front and t2 coxails in the rear.. and one 12 in the trunk.. I wanted a clean system with out huge bass... and more inportantly... I didnt wanna hear all of the road or someone to really really hear my music outside the car... ( try turning up the volume and closing the door with the windows up... you would be amazed with the level of sound that comes through without the dampening..

 

That's really not surprising. Sealing and deadening the doors, equipment aside, is arguably the biggest sonic benefit. Road noise is approached differently. Read through the material link'd above.

 

Thanks for the link, pretty good info about the different materials u can use.

 

In July 2011 we replaced the Rockford Fosgate 710 watt system with JL Audio 650CSi in the front and rear doors (Components: YES). We took out the Rockford sub and factory box out and replaced it with a fiberglass Wicked box and we also DYNAMAT'ED the trunk and doors before putting it all in. No vibrations, no rattles, no notta. You say that Dynamat is overly expensive - that's fine. I say it works great and I have had zero issues with it.

 

While I hate to be put in a position where I have to explain the original post - and its Mickey Mouse approach - Dynamat as a product cannot be looked at as a singular entity. The original Dynomat was asphalt-based. In essence, the equivalent of Peel and Seal roofing insulation that can be purchased in any DIY store. Garbage. It offered some dampening via mass loading. So, yes, it was expensive for how little good it did. The revised Dynamat is a much improved product, but still relatively ineffective. Dynamat Xtreme, OTOH, is an excellent product, Butyl-based. It does more than mass-loading by offering a constrained layer system that converts vibrations into heat. There are other products from SDS, SS and Cascade that do the same, perhaps better.

 

Interesting read, sound deadening my car is something I would love to do to it in the future, maybe this year. As a daily driver it would be nice to have less road noise and better sound.

 

Read the text link'd earlier in the thread. Deadening materials won't necessarily make the car more quiet or deliver better sound, depending on application/product.

 

great info. I'm sure once I finish this round of upgrades im gonna want to eliminate some of the sound so I def wanna keep this thread handy. Thank you guys for the info

 

Do we have a DIY for sound deadening in the EVO X on this forum? I'd love to see how to go about taking the trunk area apart to install some sound deadening material

 

Has anyone had a good outcome with sound dampening their evo?

 

I think some time ago I saw some threads about it