Decreased exhaust resonance with Dynamat!

[work2muchplay2little]

I installed an amplified subwoofer in the truck today (posted short review in accessories forum) and took the opportunity to put Dynamat Extreme on the back wall of the cab and drivers doors. I have had a rather loud exhaust resonance between 1700-2000 rpm. This is significantly better now - just an estimate but about 60-70% decreased in volume. I guess the back wall which is just plain sheet metal without any kind of dampening treatment was vibrating at its harmonic frequency with the exhaust and with the heavy/thick Dynamat has really decreased its ability to vibrate. Anyway, just wanted to let you all know! Not to worry - that sweet note from the front is just as prominent as ever

 

[John]

You're right! I added 2 layers of Dynamat Xtreme AND a layer of Dynamat Hood Liner to my back cab wall and it dampened the exhaust sound quite well. I have Dynamat Xtreme everywhere except the roof and the QC doors. At such time I need to get into those areas they will be Dynamatted too.

 

[work2muchplay2little]

That's great! You did your floor too? If so, how much difference did that make over and beyond the factory sound dampening material? Looks like you've got a real nice truck!

 

[RJ2]

dynamat

Where do you get the dynamat from. Thanks RJ

 

[JohnMcIntyre]

Dynamat everywhere

Originally posted by work2muchplay2little

That's great! You did your floor too? If so, how much difference did that make over and beyond the factory sound dampening material?

Factory sound dampening material? Is that what they call it? When I upgraded my stereo, Dynamat Extreme went in everywhere in the cab. 6,500 miles later, it was one of the best things I ever did and it helps the in-cab acoustics no end. It also deadens some of the CTD sound in the cab too, not too much though , but it sounds much more mellow now!

 

[Doc Tinker]

Dynamat isn't cheap, so I did the same thing with some roofing ice dam barrier material (called Wintergard). I think I used three layers on the back wall and two on the floor in the back seat area. I haven't done the front seat area yet.



You can take a look at the product specs here:



http://www.certainteed.com/consumer/roofing/html/r_pr094c.htm



Doc

 

[KatDiesel]

No idea how or why this thread was closed????????



Sorry for the inconvience. Its reopened as of now... and moving to Products forum since everyone can use it.

 

[work2muchplay2little]

Re: dynamat

Originally posted by RJ2

Where do you get the dynamat from. Thanks RJ

Got mine from Crutchfield (http://www.crutchfield.com) I bought the 36 square foot box. It comes in approximately 2ft x 3 ft strips and can be cut easily with scissors.



Kat, thanks for fixin' the thread. I was beginning to think I was the only one who cared (whimper)

 

[TXRam]

Nah, I am interested too.



I may have messed up here, but I ordered some material called "Damp-it" - it is in a 20oz. can and sprays on. It was around $15/can with shipping. I ordered 3 cans to do the panel behind the back seat. I found it at a place on the net , Competition Sound, when I was looking for a good deal on a Bazooka tube (enclosed, amplified subwoofer). The salesman said they preferred it over the Dynamat - we'll see if it works. If not, it sounds like something that I can attach Dynamat to - it has instructions for painting it so I would think the Dynamat would stick to it also.

 

[Doc Tinker]

The nice thing about a spray product is that you can get it into the corners and the posts. I'll bet it's just spray rustproofer though. Let us know how thick it sprays on, once you get it



Doc

 

[Hoagland]

Just as good as Dynamat

While dynamat works well its a bit up there in $$$ Try B-Quiet instead of dynamat they'll even send you some samples for 3$ if you want. I used B-Quiet in my 98' Neon R/T to stop lots of rattles when I dropped in a killer sound system, the road noise was so much better in it I've started to do the back doors (its a 4dr) and when I find a place I can work on it inside I'll rip out the seats and carpet and do the floorboards. I have some leftover from doing the R/T and my aquarium, plan to use this stuff on my 3500 when I get it, and order some more to build my A/V room. Here’s some links

B-Quiet website

My Neon's Sound System



It may take awhile to load stuff from the 2nd link give it some time

 

[Archive]

TXRam

Just an Idea TXRam... I don't know how it will take the weather. . but should be OK in TX... Maybe try spraying it on the bottem of the cab. . on the outside. . (Not on the back. . just the bottom) it might help. . if you have any left. . or maybe just an under coating. . They used to use this type of product for the inside of trunks. . (had colored specs in it. . ) or just the normal type under coating... I used this on the inside of my other trucks years ago. . some is even paintable if you wanted to go all out. . and keep the colors. . Just an idea. .

Bryan



Hey Doc... how thick is that WinterGuard stuff. . I couldnt find a spec on the thickness... .

 

[Doc Tinker]

TractorNut - It's about 1/16" thick. That's why I layered the stuff. A $35 roll goes a long way.



Doc

 

[Cooker]

I have bought and used many sheets of a sound dampening material from a local audio parts supplier. It's is not Dynamat but it looks and feels the same, and functions the same as the least expensive dynamat. The best thing is it's only $5/sheet, and the sheet is about 1. 5'x3' I need some more to do the doors and floor on my CTD (I already did the roof and rear of the cab), but a friend told me the comapny was closing their storefront. At $5 a sheet it's a steal IMO and it's really easy to double layer it for added results.



-Ryan

 

[RDusch]

Another product that has worked well for me is a product available from most commercial insulation suppliers, its called FLEX CLAD 400 looks identical to dynamat and seems to work as well, and for 45 bbucks for a 3 x 30ft roll you can put down 2-3 layers ,i lined my whole cab with it.



Rick

 

[John]

Re: dynamat

Originally posted by RJ2

Where do you get the dynamat from?

RJ2, I purchased mine from Summit Racing. Although expensive, it is worth every penny... to me.



TXRam, Dynamat also makes a spray-on accoustical damping material, called Dynashield. The Dynashield is a high-build type of material that can be layered and top coat painted if desired. A Dynamat tech. told me it could be used as an undercoating as well as a rocker panel shield.



Funny, I like how everyone compares their product to Dynamat, even the posters on this thread. The fact is nothing compares to Dynamat, especially their new Xtreme! The Dynamat Super has twice the sound damping quality as the Dynamat Original and the Dynamat Xtreme has four times the damping quality as Dynamat Original (twice that of Dynamat Super).



Dynamat, when only the very best will do.

 

[TXRam]

Well, I went ahead and ordered 33sqft ($53) of the B-Quiet Extreme (yes, John, it is compared to the Dynamat Extreme, but at about 20% of Dynamat's cost, so even if I have to use 2X as much, it'll cost me less than 1/2 of Dynamat's cost).



I plan on using it behind the back seat and using the Damp-It spray inside the quad cab doors. I'll update this as soon as I get it and get it installed.

 

[John]

<<<< Dynamat User

Originally posted by TXRam

Well, I went ahead and ordered 33sqft ($53) of the B-Quiet Extreme (yes, John, it is compared to the Dynamat Extreme... )

Every time I hear "it compares to" Dynamat, and subsequently request information substantiating same, I never hear a "good" answer other than it was stated as such by the manufacturer of the "other" acoustical material or the car stereo shop selling it.



..... kinda like a genuine imitation Rolex.



One thing though, I have been using Dynamat since it was first released for sale on the market (back when "original" was not named "Original"... it was the ONLY game in town). I have had many friends use other brands of damping material in their cars and trucks and have never once seen where their cut rate damping jobs provided superior results. Maybe cost per dollar invested, but not regardless of price.



PS: 33 sq. ft. @ $53. would be 33% the price of Dynamat Xtreme JFYI

 

[Millfly]

Just completed lining the truck with Dynamat Extreme. Purchased two bulk packs at $152 each. That is about $100 a pack off list price and is 36 sq. feet. Got it on the web from Audio-N-More. Lined the front two doors, floor, firewall (as much as I could) and the rear panel. Really cut out the road noise! I also have ATP Blankets on the engine. Will put a sound meter on the truck sometime in the next couple of weeks to see what the sound reduction was.

 

[John]

Excellent Millfly!

I remember now... you were the very first on this BB to order the ATP sound deadening kit for your Ram and wrote a very comprehensive article on same, complete with sound pressure measurements.



You didn't mention anything about the Quad doors... did you install any there? If not, do you plan to? I'm going to tackle my Quad doors and ceiling after I get a few other projects completed.