Frost King and Duramat Hoodliner: Completely ineffective at reducing cabin noise

I noticed on a niece's Lexus that they used a outdoor type carpet in the wheel wells. I had wondered why/ how her car was sooo much quieter on the hwy. than a Mercedes.

 

What was your *perception* of the change in noise?

As you said in your OP, the perception of noise, and the measured dBs are very different.

What would be more telling is if you were able to chart the second by second dBs over a longer period of time. Your readings are simply when you happened to look at the meter, and who knows what the temporal resolution of that meter is.

The other thing to think about is if you are taking a MAX reading, or an average reading. There is a very important distinction. Because you were not able to perfectly insulate *everything*, it's likely the MAX dBs weren't effected, but the average may have been effected to a much larger degree.

The average - or the noise level that is most common is what will have the greatest effect on how you perceive the noise and how "tired" it makes you. A loud blip here and there doesn't really do much except affect your max readings.

 

I think this test needs to be done with material that is made for sound quality. I now only have wind noise coming from the window area and barely any road noise. Can speak normally too.

 

I don't perceive the cabin noise to be any less. The only difference in sound all of this has made is that now the doors close with a solid thud, no rattling.

The sound meter has a relatively slow response rate. So it would not be good to use to capture the decibels from a short and loud sound.
While taking the readings, the numbers on the meter are constantly changing and can swing ±3 db or so. The values I reported are of me mentally taking note of the number that is most routinely shown, and it was done over the course of a few miles or so, but on multiple separate occasions. So in this case I am reporting the mode and not the average. Also note that the values I reported are whole numbers, as the meter provides a tenths of a decibel. I rounded the numbers to avoid a false precision.

 

About the sound meter's response rate: I just mean how often the meter compiling, interpreting, and reporting those measurements to the screen, of which you end up reading. And if the meter is reporting the max value, or a mean, or other for some specified time period - like the max for a 5 or 10 second interval, etc...

It would be "better" to have a more comprehensive graph of the instantaneous measurements to be able to run statistics off those values, rather than the human-entered values.

Given that you didn't really perceive much of a difference in the noise, that does jive more or less with your measurements.

Given that noise does effect how quickly people get fatigued (much of it is subconscious), it would be interesting to see how you start feeling over the next couple weeks even if you don't immediately perceive a change in the level of noise. You threw in a TON of insulation, so it's hard to believe there isn't SOME affect on the noise levels, regardless if your immediate perception or your measurements don't reflect that.

 

So I'm gonna just throw this out there but it was my understanding that the frost king / dynamatt material was for vibration not sound deadening. That's why they say only for 1/3 coverage.
If up want to deaden the sound you need to use massloaded vinyl with a foam decoupler.
Also I believe someone else had great results by putting a sheet of plywood against the back wall .

Good luck and thanks for sharing your story and results.

 

This is my understanding as well. At least the OP has one layer installed already. My understanding is that the vibration/anti-resonant lay can be strategically applied as sparse as 30% of full coverage and still produce the desired effect. The next step is a closed cell foam layer(I have a huge roll of 1/16” neoprene for this) with 100% coverage followed by a mass loaded vinyl with as close to 100% coverage as possible.

I have the materials in my shed for a sound proofing job and have actually installed some noico vibration material on the back wall, floor pan, and doors already. No real reduction in sound yet but I wasn’t expecting one until the other 2 layers are installed.

 

do you have to roll the it on to get a good seal? did not look like it was. I know for Noic, Dynomat etc you have to roll it on to get a good seal or it does really do anything just makes the panels, doors etc heavier. I would be super bummed. Never thought to get a reader to see. I have done the doors and the rear of the cab but still need to complete floor and roof.

My largest noise areas are the roof and the tires outside so the back part. It has gotten a bit better but still pretty noisy. Next up I need to do the headliner. Having a rack and stuff up top it gets pretty noisy in wind and on the road.

 

I have been thinking of adding Noico's second layer. Feel that is really worth it then?

 

I’m not familiar with their “second layer” product tbh. Is it a closed cell foam product?

 

Not sure but you want thisSecond Skin Luxury Liner Pro - Mass Loaded Vinyl Soundproofing for Cars, MLV Sound Barrier with Closed Cell Foam (1 Sheet)

$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/dp/B01NAFWT3S/ref=cm_sw_r_cp_apa_i_kQ2LDb9V6CS4J
And with this between the mlv and door ect..Neoprene Sponge Foam Rubber Sheet Rolls 15in x 60in (1/8in Thick)

Lazy Dog Warehouse Neoprene Sponge Foam Rubber Sheet Rolls 15in x 60in (1/8in Thick)

https://www.amazon.com/dp/B07BKP6KFX/ref=cm_sw_r_cp_apa_i_rT2LDbVMERCYF

 

I've referenced this article about a guy that deadened a Hummer with Maybach materials.

https://www.flashoffroad.com/Improvements/Insulate_diesel/crockwell/soundproof.html

Then I know a guy that contracts for a company that built custom interiors primarily for Falcon jets. This link has some interesting sound deadening material for aircraft.

https://www.aircraftspruce.com/menus/ap/soundproof.html

 

This is what I added to my door panels with a noticeable change. 1/8 rammate foam, sound deadner, mass loaded vinyl and as crazy as it sounds UHaul moving blankets. Used spray adhesive to hold it to the back of the door panel.

 

Sub.

 

interesting idea there.

 

I'd be curious to see the sound meter readings with your elbow not resting on the center console. Sound is vibration. Your truck vibrates. The bones in your arm carry vibrations. Maybe nothing, but I'm curious.

 

Here's the pdf of how to soundproofing from that web site.

 

@mechanicjon . Did the moving blanket really make a difference Is it more to stop the rattels?

 

What an incredibly informative read. Glad you linked it, I'dve never noticed it at the site

 

It made a difference to my ears. If it was the sound deadening mat or the mass loaded vinyl or the blanket that did the most. I don't know I did all 3 at the same time.