Technical Anyone ever used mass loaded vinyl under the carpet?

I finished the 55 flooring this weekend, covering everything with Kilmat. I was reading online about a stuff called "mass loaded vinyl". I know they are using it in the never cars. From what I gather, you don't glue it down, it has to float on a foam of sorts.

Anyone know anything about it? Everything on the web seems to be geared towards sound engineers. I need laymen's terms. I'm simple.

 

They're also using EFI and ABS and stuff in newer cars. That doesn't make it right for our cars.

 

I would advise to go to Harbor Freight and buy the rubber pad/cushion. Aaron covered my floors of the Merc and you cant believe the difference. It works great for added insulation. Sorry, not really what you asked, but this works great and cheap....

 

I knew it wouldn't take long for the traditional police to show up. It's freaking insulation, that goes under the carpet. If it makes everyone feel better, I will tell you that I used old burlap sacks sewn together with asbestos string.

 

You might find that the stuff you already installed, does what MLV does, but it's in a form that is easy to install in cars. Sheet mass loaded vinyl would work great if the floor were flat.

 

Now your talking old school.

 

Roothawg, with that excellent install of sound deadener you have sound dampening and some insulation from outside temperatures covered. When you lay your carpet over some type of carpet pad I think you have all the bases covered. I think you've done a far more thorough job than present day factory at that point.

PS, Squirrel ain't a cop, he's a hot-rodder.

 

Cosmo, that helps with the rattles, but the actual sound dampening has a different requirement. I really don't want to use jute pad, because if it ever gets wet, it stays that way for a while. That's where the old dead dog smell comes from. I am putting new carpet in and would like to make it last as long as possible. The Loaded Mass Vinyl is supposed to float and act as a dampener for certain frequencies.

 

I think the problem is that you kind of need to be a sound engineer to figure out what the frequencies are, and what is the best way to attenuate them.

Sent from my Trimline

 

I hear you with the wet jute and horsehair. I think you are going to have a different experience altogether with those fresh rubber seals you have on all you windows, doors and trunk. While you are in the install stage why not get it as quiet and comfy as it possibly can?

There are so many new products out there, some in spray form. I hope you get a lot of responses from empirical experiences.

 

Agreed. I looked at a lot of the reports, but without a standard, it means nothing to me.

Cosmo, this car is for the wife. She is adding a lot of things that she has on her new Lincoln. electric door locks and trunk, a/c, power 4 wheel disc brakes, Stereo system etc. The powertrain is out of a 2000 Explorer 5.0/4R70W, 8.8 with posi .

It's not traditional, but the car will mimic a 1955 mild custom from the outside but drive and handle like a new car.

 

Would 2 or 3 sheets of Rubber roofing glued together work?

 

I used the stuff from Homo Depot ,it seemed to help a lot. Just my opinion.

 

What stuff is that?

 

The very basics...

Everything in the world has a resonant frequency. Rap your knuckles on a fender, the side of your house, your friend's skull, whatever. The resonant frequency for that interaction is what you hear. It is mechanical energy being converted into sound (and heat).

Increasing the mass of an object, in a generic sense, tends to reduce resonant frequency by simply adding density (use thicker sheetmetal for a fender, use brick instead of vinyl siding on the house, your other friend with the thicker skull, etc.)... thus requiring more mechanical energy to generate similar sound levels-- or said in reverse, for the same amount of mechanical energy input, less sound.

The term mass loading typically refers to a specific technique. Here, rather than simply using thicker metal for your fender, you attach a specific material that has a VERY low resonant frequency (usually below the audible range). When the primary object (metal fender) vibrates, that energy is captured by the attached material, and converted to the lower resonant frequency of that material. As a simple example: rap your knuckles on the flat part of your quarter panel. Now, place the other hand flat against the rear of the panel and rap again. Voila. Sound controlled. Some of the energy that would have caused the fender to rattle just went into the flat hand on the back. Your hand has a much lower resonant frequency, so you didn't hear it as much. Another simple example: Blob a fat dollop of silicone caulk on the back of the fender where your hand was. The silicone will now be the "sink" for some of the energy in a rattling fender.

All of these sticky mat materials use this principle to manage sound. Their composition materials, density, etc., will all affect at what frequency they do their jobs.

Keep in mind this is a very simplistic explanation, missing lots of very significant details if we decide to have an actual engineering discussion.

 

Probably Peel and Seal. Its aluminum foil backed with rubberized asphalt adhesive. It is used to seal roof flashing. I used it to deaden a parcel shelf I installed speakers into and it worked great.

 

That's basically what the Kilmat is. This stuff is supposed to be a thick rubber mat that has a felt or backing on it.

 

Anti-Fatigue mat? This one? https://www.harborfreight.com/anti-fatigue-roll-mat-61241.html
or this one?
https://www.harborfreight.com/4-piece-anti-fatigue-foam-mat-set-94635.html

 

I would recommend a synthetic felt you can order it at a carpet store 1/4” and 3/8” will keep it a quite as you can get! Just my 2 cents!


Sent from my iPhone using H.A.M.B.

 

I picked up some anti fatigue mat on amazon and used it on the floor of my 58. I started with fatmat rattletrap on the firewall, floor, doors and the back of the cab. From the top of the firewall to the seat I used fatmat floor liner. I then cut the anti fatigue mat to cover the floor, covered it with jute and finally some loop pile carpet. Overkill? Probably, but it made a dramatic difference compared to the pre sound deadener noise levels. I would do it again in a heartbeat.

 

Thanks guys. Researching now.

 

What did you use to hold the anti-fatigue mat down to the firewall?

 

I only need a supply of pre 65 gas to finish my current build. I scrounged all the air for the tires from old junk yards. The vintage oil was easy

 

i installed a hard top on an old gpw jeep, over 30 miles an hour you wanted to bail out to get away from the noise. to simulate what it was like take a metal trash can, put it over your head and have one person hit it with a mallet while another guy tries to sawzall through it.
i lined the floor with stall matting [1" thick rubber] and glued 3/8" felt to the roof. it is now comfortable , for one of these turds, to drive.

 

If you want to do some research, this site has a lot of great info on it:
www.sounddeadenershowdown.com

 

I only used it on the flat portion of the floor. The pic I posted shows the fat mat floor liner which is self adhesive

 

All I have to add to this conversation (at this point) is to pay attention to any foam mat you use. There is open cell and closed cell. Closed cell will be much better to alleviate prolonged moisture issues. Closed does not absorb moisture, where open cell does.

I work in the HVAC engineering/design industry and there are some duct insulation and 'lagging' products that would work great for automotive insulation/sound deadening.
As an example, I've purchased a few rolls of Alumaguard jacket for myself and friends to use in place of Dynamat. It's pretty much the same thing, sold in bulk in a roll:
http://www.polyguardproducts.com/mechanical/weatherproof-jacketing/alumaguard-2/

 

That’s actually what prompted me to start this thread.

 

The fat mat floor liner looks the same as mass loaded vinyl

 

It probably is. Just marketed differently.