Kilmat Door sound proofing

Hey guys, trying to sound deaden the truck. I'm going to hit the floor in a couple months. So far two layers inside door and one layer under the panel have not helped at all with road noise...

 

My biggest improvement came from doing the roof.

 

I did all the doors (both inner panel and outer panel) and the back wall below the window. Noticed a slight difference, mostly that the doors are tank-like now. I think the floor footwell needs to be addressed. I also added sections of D-seal weather seal along the fwd and upper half of the door jambs (truck body side) and that made an improvement in wind noise. Well spent $8 vs all of the Killmat.

 

That is interesting!I would have thought the floor would have had the most impact but I could see the roof acting like a reflector. I wonder if models with the moonroof would have the same results, likely worse.

 

Ohh and this is how cra cra I went on my doors, I also did the inside of the outer panel like you did.

Unluckily for me, I was given the opportunity to do some Chemo last year, and it made my ears super sensitive now, along with tinnitus. So had to help myself out some...

Yes I know, way overkill.

 

That's what I did also. I put in new upgraded JBL 6x9's and an amp while I was at it.

 

I'm really interested in doing the roof. I definitely head the road noise, and I have a prinsu rack. Even opening the sunroof slider increases road noise.

 

Where exactly did you put the d seal?

 

Does this help muffle screams coming from the inside of the cabin?

 

https://www.acehardware.com/departm...s/weather-stripping/weather-stripping/5315445

 

Please Watch video at 6:50 mark:
https://www.youtube.com/watch?v=KOPH37RbJ28

So true Lol!

 

Didnt help with road noise because butyl/alum. is used as a antivibration layer or dampener. It would help with traveling panel resonance though. To actually diffuse or eliminate wave frequencies you would need a material both dense enough and thick enough to absorb the waves. Mass loaded vinyl helps. @Ericbike6 appears to have utilized a CCF to assist in absorption, it works, better than butyl/alum layers purely due to the thickness of the material. Actual sound deadening is a targeted endeavor, find the frequencies you wish to eliminate before deciding upon the application. Road noise seems to be in the approximate 1000hz range, so you would need to find and appropriate material thickness to prevent the sounds wave length from passing through the material. Generally for a frequency that low the material thickness would be sizeable for a vehicle. I've seen studies suggesting material thickness in the neighborhood of 1". Some vehicle application mass loaded vinyl can be between 1/4" and 1/2" thick. Once coupled with butyl/alum, CCF and MLV you begin to get a total depth of nearly an inch.

Try this:
If you were to couple 80mil butly/alum:

Noico Black 80 Mil 36 Sq Ft Car Sound Deadening, Butyl Automotive Deadener Restoration mat and Noise dampening Insulation

https://us.amazon.com/Noico-Deadeni...ld=1&keywords=noico+red&qid=1607980855&sr=8-9

With 315mil CCF:

Noico RED 315 mil 20 sqft Car Sound Insulation, Heat and Cool Liner, Self-Adhesive Closed Cell Deadening Material (PE Foam Sound Deadener)

https://www.amazon.com/Noico-Insula...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

And MLV:

$85 Second Skin Luxury Liner Pro - 2 in 1 Sound Insulation for Cars - Mass Loaded Vinyl and Closed Cell Foam - MLV Noise Barrier Made in USA (1 Sheet)

https://www.amazon.com/Second-Skin-...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

With that your total thickness would be ~.77". It would work considerably better at actually canceling out a lot of the road noise. The issues though, it would cost a ton of money. MLV is heavy and mounting it horizontally in a vehicle is a challenge. You would still have sound permeation. This quickly ends up being why people often settle with just dampeners, that dont eliminate noise from the outside, but rather eliminate some of noises caused by the vehicle panels.

I suppose you could also generate a 1000hz signal in an inverse phase and that would effectively cancel the sound. That would be interesting, might even be cheaper.

These products do serve a purpose, I just think theyre intentionally marketed as "noise canceling" without specification to mislead people into thinking they can lower the entire noise floor in a space.

 

Solid advice, sealing the door panels is a good idea. Despite his issues with putting matting everywhere, this is one place it works well. A sheet over the openings is rigid enough to correct this, it also seals well.

I did this on my Crewmax in the past, honestly a lot of people would be pleased with the stock systems bass if they simple sealed the door up like this. Pretty cheap and easy option.

 

This guy summed up sound deadening pretty well!

 

Thanks!