Dynamat Poll, yes or no? If so how much?

I voted entire truck, but I vote against Dynamat.

It's a product that was marketed very well, but doesn't do the intended goal in a very efficient manner.

Check out http://www.sounddeadenershowdown.com/ for all you need to know about sound/vibration isolation.

I did a combo of Constrained Layer Damper (CLD) tiles, mass loaded vinyl (MLV), and Closed Cell Foam (CCF) in my car and the results were pretty impressive.

I also used some extruded butyl rope between the outer door skin and reinforcement bars in the doors.

The guy that runs that site, Don, is very knowledgeable and helpful in deciding upon the best approach. I ordered the MLV from a different site though, which I found to be the best price. His was slightly higher. Otherwise, I called up and he figured out how much I needed for my vehicle.

I'll be using the leftover product from my prior install in my Taco in the next couple of weeks.

The CLD product is seen here. No need for 100% coverage. That'd be overkill. Check the video from the CLD link above. Pretty cool. There is also CLD behind the vapor barrier. The EBR is also behind there.


The MLV is beneath the CCF seen here. I velcroed the MLV to the door, trimmed to fit, then removed and glued CCF on top of it.


More CLD tiles seen here...




The MLV and CCF went down on top of the CLD in these areas as well. No pics though.

Can't wait to attack the truck so that I can compare the before & after. The TACO is pretty noisy as is.

 

I did Dynamat on all four doors and the rear since I have two subs back there. It was 75 per door installed and 150 for the rear. I got it done here on Guam where it's hard to get anything done and they want you to pay extra for everything. It's not as difficult as he's making it sound or I would have paid a lot more.

 

Hey Jax here too, I just ordered a pack of BXT II and peal and stick ensolite from Rick at Raamaudio and some of that rope from Don, Don has lowered the price on his MLV and sells by the foot or sheet now, I only plan on doing the floors with the MLV and the Raam pack for doors, rear and roof. Looking to have all but the MLV here for the long 4th weekend.

 

I did a test.. after installing raammat in the doors, the shi$ was louder. bottom line, it improves the quality of the sound. I'm a sound-deaden snob now.

 

You know what they say...once you deaden, it's sound quality heaven

 

Haven't read this entire thread, but as a previous car stereo installer and competitor, we found Dynamat to be over-priced for what it did. While I do not have experience with some of these new items you guys are discussing in this thread, I have a lot of experience with (and a lot of faith in) ice and water shield roof underlayment. It is self adhesive (incredibly so!), very flexible (more so than Dynamat), and does just as good a job as Dynamat (if not better) at about 1/3 the cost. The kind I am referring to has a silvery backside to it and can be found at many home improvement stores (I just picked up a few rolls at my local Home Depot).

I just recently installed the JL Audio dual 10's Stealthbox in my DC and the back sheetmetal was was a total buzz-bomb (yuck!). So I took some expanding foam to all the hollow areas and then used ice and water shield roof underlayment (total cost of these items: $39.83). End result was total removal of all the buzzing noise. Now, the only thing that shakes and vibrates are the back windows (the JL Audio Stealthbox really hits hard!).

Hope this helps!

 

Roofing material has no viseolastic properties and is less than ideal for deadening. It's certainly better than nothing but the sheer amount you'd need would cost waaay more than a good constrained layer dampener with good viseolastic properties.

 

Wow Italyn, I just had to look up "viseolastic properties"! Like I said, I paid a total of $39.83 for 1 can of spray foam and two small rolls (4" x 25') of ice and water shield roofing underlayment to remove all the transient vibration and buzzing from my back wall caused my the subs. The underlayment was placed as a single layer (with overlap), so I really did not use that much. To be clear, I am not referring to the sheets with embedded asphalt in them. These are sheets of a very sticky rubber compound with a foil backing on them.

I don't know all the big words and scientific theory....but here's what I do know; Dynamat used to send dealers a display that had a piece of untreated metal and a piece of Dynamat treated metal so that people could hear the difference. We conducted (and displayed) the same thing with a piece of untreated metal, a piece of Dynamat treated metal, and a piece of underlayment treated metal and the metal with the underlayment provided the same vibration dampening effect as the Dynamat at 1/3 the cost.

I just offer up this material as a FAR more cost effective method for anyone considering Dynamat.

*edit* Also, looking up "viscoelastic properties" brought up Second Skin Automotive Insulation's website (http://www.secondskinaudio.com/vibration-mat/damplifier.php) which, to my untrained and inexperienced eye, their Damplifier looks eerily like the very same underlayment that I am referring to.

 

If it's really a butyl rubber compound then it might be somewhat decent. You're exactly right about the asphalt based stuff; you want to stay away from that. It's the heat that will end up killing it.

Dynamat is quite expensive and I actually used Second Skin Audio products for a long time because back then, it was cheaper than Dynamat and the best stuff on the market. Now, Don at Sound Deadener Show Down has the best stuff IMO. I did the whole Tacoma with his stuff and I'm very happy.

 

I am planning on using these same products on the back wall of my Tacoma (to start). I was under the impression that the proper sequence was:
metal
CLV
CCF
MLV

Is this not right?

 

This is true Rob. I did my doors with the CCF & MLV reversed. Not on purpose! I had already measured, cut, and glued, so I went ahead with the install. I don't know that it matters that much, but I did it correctly in the rest of the car.

 

I believe Don from SDS said in a post over on diyma.com he had done doors both ways, CLD->MLV->CCF, and CLD->CCR->MLV, and the results were the same.

He just said he preferred the CLD->MLV->CCF method better since the CCF on the outside seem to help the inner door panel fit back on more snugly to eliminate rattles, moreso than if the MLV was on the outside.

 

OK, just wanted to check as in my case the MLV is likely going to wind up exposed when the seats are down and it obviously should be much more resilient than the CCF.

 

Switch the left and right door MLV/CCF assembly. They are mirror images

 

Usually so, but in the case of my Corvette's doors, they actually bolt on in two different spots. I didn't want to have to cut new holes, and have to use more velcro than I needed too. Trivial things in the grand scheme, which is why I decided to just leave 'em.

 

Ahhh, I thought you were talking about the Tacoma.

I think you should be fine

 

Ok did my doors this weekend with BXT II and peal and stick ensolite from Rick and Butyl rope from Don, new reading in the cab at 70MPH are 68.7dB concrete and 66.9dB asphalt. Need to get the MLV from Don yet and do the back wall, ceiling and roof yet.

 

Wow! That's a big difference, and that was just doing the doors!? Impressive. How much of the peal & stick ensolite did it take to do your doors?

 

I ordered 3 yards and used just less than half, have enough to do roof and some of the back wall, it works out to about 14 sq. ft. a yard and it is sticky but easy to cut with scissors, just had to clean them with goo gone after each door.

 

Well, I measured mine with my dB meter last night taking the wife to the airport. Did it a few times (45 min drive) @ 70mph on the highway to check for accuracy. According to my decade old Radio Shack analog spl meter, with slow response and c weighting, it was about 84 to 86 db in my truck.

Here's the kicker. I've completely done the truck in Raammat BXT on the floors (doubled in a few spots), BXT II on the doors, back wall, and roof. Ensolite over top that. And yes, I now know it's not needed and overkill, but I did complete coverage with the deadener.

That was before I read Don's site. I've got a roll of MLV and supplies in the garage, and my truck is coming apart as I type.

I REALLY hope the MLV quiet's down my interior. It actually doesn't seem that loud in there, but....

FYI, my truck's an access cab, but I've got Goodyear Duratrac's on it. LOL, probably most of the problem right there.