Sound deadening questions

Hi All,
Thought I might be able to get some answers here, I have been reading several forums and am confused by what I am reading.
First...
I have a 2020 Ford Transit Connect Cargo van.
I had a local shop install my mid & tweeters and sound deadening to my doors.
I had them use Kilmat because I have a couple boxes in my garage.

my question is, for the rest of the van. I will use kilmat, then do I need use use something else On top of that?
I am just trying to make vehicle quieter, It does resonate pretty well because it is a hollow metal box...

Sorry for Noob question..
Thanks for any and all help.

Maybe just do the damper and see how much of a difference it makes. I'd expect it to be significant in that van. It's not like you have to rip the interior out again if you wanna go further.

Does it have a rack on it? I'd definitely want a barrier on at least the roof if so. Those make all kinds of noise.

No roof rack. Yeah I will post more pictures as I continue with the Kilmat.
I made a bed with storage underneath and room for a large sealed enclosure once I figure out what size box to use with this 12” Sub.

there's usually 3 products together. CLD/deadener, closed cell foam to decouple, and a sound barrier to stop noise. CCF usually to stop plastic panels from buzzing next to other surfaces.

probably want a sound barrier next, like mlv (1/8" thick, 1lb per sq ft) or sheet lead (1/64" thick, 1lb per sq ft)

do all once while it's apart. pulling it all apart to add other stuff kinda sucks :)

I'd run VB2 on almost every surface in that mamma-jamma. Then run VB4 on the floor space. After treating the large areas with a CLD of your choice.

I'm shopping for an inexpensive one myself, now.

FWIW - I don't skimp on actual damping material. You need damping material to really adhere well, and be good, to absorb vibrations. Don't skimp on that.

I do buy cheap CCF and MLV. Most recently I actually gambled and bought some CCF on Wish - seriously - and it actually was great. Cost me like $100 for 100 sq/ft. Bargain.
CCF is a barrier product, there's some who say it does nothing- I don't know, seems you need a barrier to stop sound from penetrating - the barrier layer needs to NOT vibrate, so MLV can absorb the sound.

MLV is known to only be manufactured in a few places. It's basically "all the same". And it doesn't even have adhesive to worry about, because you again don't want it directly stuck to your vehicle's vibrating panels. It's heavy as hell - if you care about that like I do (I like small, light, fun cars that handle) buy 1/16"
It also doesn't heat form too well. I mean, it'll stretch like vinyl but unlike vinyl you aren't gluing it down. I used 10mm CCF in my hatch so I'd have a good barrier layer, because it's a hatchback and I want to try to stretch it and form it to my spare tire well - that's a hell of a tall ask for a stretch even if I'm gluing it - which I'll have to - hence the thick barrier layer. I'll probably still end up with seams and patchwork in the well :lol:

But that's the gist:

Damping material - this absorbs vibrations. You don't need 100% coverage, just enough to stop the panels from vibrating. You want decent stuff with decent adhesive, and clean your surfaces and use heat.
Closed Cell Foam - comes in 5mm-10mm thicknesses. It's just a barrier layer to decouple the MLV. Thicker is better except you have to fit these things behind panels, so keep that in mind.
Mass Loaded Vinyl - comes in 1/16" and 1/8", and damn the 1/8" is heavy. You know those lead blankets when you get Xrays? :lol: This is what you use to block outside sound from entering your vehicle, and you have to do a good job so you don't have gaps where it can get through.

It's a hell of a project since you basically have to strip your interior out, then go through the process three times with three layers - so I'm envious of the fact that you have a van to do this to. :cool:

Quote:

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Originally Posted by Pb82 Ronin

I'd run VB2 on almost every surface in that mamma-jamma. Then run VB4 on the floor space. After treating the large areas with a CLD of your choice.

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I have to also agree with this-
This is the all-in-one solution that's easiest to install... it's just much more expensive.

Doing it my way, I end up with about $1/foot for each layer - and actually call it $4/foot because decent damping material costs more. So for 150 sq.ft. for my little Civic hatchback, we're at $600.

If I did Cascade VB2 and VB4, I'd be so much happier from an ease-of-install perspective - but is $10 sq/ft. for VB4 and about $6 sq/ft. for VB2. Call it $8 sq.ft to buy half and half of both for rough estimate purposes - So $1200 for my 150 sq.ft.

Either way, it's an investment - but a worthwhile one. You really might be grateful to spend the extra $600 to make the installation a bit more foolproof and definitely less labor-intensive.

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Sorry for odd pictures no matter how I format them they come out wrong, not sure what the issue is. So as you can see I did get a start on the sound deadening.
I sure appreciate all the help and tips all!
Thanks

I will look into this as my next step for sure. Thanks again for the solid tips.

Oh boy..

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Oh boy as in..... good job or oh boy as in ..... well hey if I did mess up it’s all good. That is how we learn.

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Originally Posted by SQFord

Oh boy as in..... good job or oh boy as in ..... well hey if I did mess up it’s all good. That is how we learn.

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Oh boy as in lots of bad info from a particular post, and oh boy as in, well, frankly.. killmat isn't worth the effort it takes to install it. Very poor performing product.

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Quote:

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Originally Posted by SkizeR

Oh boy as in lots of bad info from a particular post, and oh boy as in, well, frankly.. killmat isn't worth the effort it takes to install it. Very poor performing product.

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Don't like the implication that MLV is all basically the same?

Or that CCF doesn't block sound and just makes sure the MLV doesn't vibrate with the underlying surface?

The vagueposts are really what's unhelpful.
At least other people try.

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Quote:

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Originally Posted by geolemon

I do buy cheap CCF and MLV. Most recently I actually gambled and bought some CCF on Wish - seriously - and it actually was great. Cost me like $100 for 100 sq/ft. Bargain.

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Bad idea. Ccf is important and shouldn't be skipped on as well.

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Originally Posted by geolemon

CCF is a barrier product,

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No its not

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Originally Posted by geolemon

so it can absorb the sound.

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No it won't. This is not what ccf is for or does.

Quote:

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Originally Posted by geolemon

MLV is known to only be manufactured in a few places. It's basically "all the same".

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Correct, but so long as its Virgin. Cheap stuff is recycled

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Originally Posted by geolemon

buy 1/16"

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Don't do that. Doing a noise barrier is a big and tedious job and you want to make it worth your effort. Use something thats at least 1Lb/sq foot

Quote:

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Originally Posted by geolemon

I used 10mm CCF in my hatch so I'd have a good barrier layer, because it's a hatchback and I want to try to stretch it and form it to my spare tire well - that's a hell of a tall ask for a stretch even if I'm gluing it - which I'll have to - hence the thick barrier layer.

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Again, no

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Originally Posted by geolemon

Damping material - and use heat.

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Constrained layer damper. Do NOT use heat. It will break down and ruin the butyl if not careful. Also, if you are using a product that needs heat its a product you shouldn't be using. Its just unnecessary

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Originally Posted by geolemon

Closed Cell Foam - comes in 5mm-10mm thicknesses. It's just a barrier

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No. Ccf is not a barrier

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Originally Posted by geolemon

layer to decouple the MLV.

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There you go. This is one use for it

Quote:

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Originally Posted by geolemon

Mass Loaded Vinyl - comes in 1/16" and 1/8", and damn the 1/8" is heavy. You know those lead blankets when you get Xrays? [emoji38] This is what you use to block outside sound from entering your vehicle, and you have to do a good job so you don't have gaps where it can get through.

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Yes, THIS is a barrier

Quote:

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Originally Posted by geolemon

It's a hell of a project since you basically have to strip your interior out, then go through the process three times with three layers - so I'm envious of the fact that you have a van to do this to. :cool:

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Yeah, so use the right products to make the effort worth it

http://www.resonixsoundsolutions.com...ce-information

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Quote:

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Originally Posted by SkizeR

Bad idea. Ccf is important and shouldn't be skipped on as well.




No its not





No it won't. This is not what ccf is for or does.





Correct, but so long as its Virgin. Cheap stuff is recycled





Don't do that. Doing a noise barrier is a big and tedious job and you want to make it worth your effort. Use something thats at least 1Lb/sq foot





Again, no






Constrained layer damper. Do NOT use heat. It will break down and ruin the butyl if not careful. Also, if you are using a product that needs heat its a product you shouldn't be using. Its just unnecessary





No. Ccf is not a barrier





There you go. This is one use for it




Yes, THIS is a barrier






Yeah, so use the right products to make the effort worth it

www.resonixsoundsolutions.com/reference-information

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You are completely misquoting me, and it takes an asshole to do that to try to paint a false narrative.

I took the time to very explicitly describe that:
A) damping material is for vibrations.
B) ccf is a barrier between that and mlv, to decouple them so the MLV isn't vibrating.
C) that MLV is what's blocking the sound.

I also qualified that I'm personally only looking to lighter weight alternatives because I specifically have a light, sporty car and weight is the enemy. Your opinion on my preference on prioritizing weight is irrelevant.

Here's the thing about quoting people:
1) you have an obligation to read what they wrote, if you are going to make commentary on it at all - especially a charged, accusational commentary.
2) it's nothing short of asshole to try to take quotes out of context to try make it look like what you misunderstood.

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EDIT: Since one SINGLE vague word in my original post was so aggressively trolled, and with such a narrow-minded rant of aggression, rather than inquire on a potential misinterpretation or vagueness...
...I've edited that post, replacing one single word "it" with "MLV". I highlighted that in red and bold, in part to illustrate how aggressively this troll has tried to creatively edit and misquote what I've written to serve his misinformation attack. One word is not 11 quotes.
Readers beware this guy and his aggression.

Also -
The points I made don't come from my imagination. They are real.

1) Don't skimp on damping material. It matters.
2) All CCF really does is act like the pad that it is. It stops the vibrations of the underlying surface from being passed physically to the MLV.
It's a vibration barrier - nothing more. It doesn't stop sound. Other than adhesive, there's not much "quality" argument. CCF is CCF. You buy the thickness you need. It decouples vibration.
3) MLV is MLV. Even many of the brands admit that they source from the same contract manufacturers. And many of them share dB-by-frequency charts to show effectiveness. They match.

None of these are false statements.

But if you have test results that show how one CCF objectively outperformed other CCF in a "head to head CCF comparison" that I'm not aware ever occurred (and I suspect the reason it hasn't is exactly what I'm saying), please feel free to share that set of measurements.
That WOULD be a positive contribution to this thread.

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These test results from Justin Zazzi do that.
https://www.dropbox.com/s/5yd1s6vbxb...0v1.3.pdf?dl=0

Actually, yes but unfortunately no.

That's an excellent test setup and test candidate lineup - including the inclusion of MLV with no vibration barrier between it and the damping layer, to really serve as a control variable.
I personally love the inclusion of all these alternative materials, including some pretty ghetto ones and a few pretty clever ones. That's really the main focus of his test.

As it relates to my point, however, that all CCF are pretty equal - the only items that correlate to "CCF" are:

• Sonic Barrier 1/2" (this is just 1/2" CCF)
• Sonic Barrier 1/4" (I *think* this is just 1/4" CCF - this is now discontinued and some of Sonic Barrier's other thicknesses are actually composite layered products)

There's also a "generic" foam option listed, but that's significantly not CCF - that's open-cell foam. (it performed worse than I would have guessed, but that's irrelevant)

The thing I'd also question is the very small sample squares, which could just be called into question for not representing real-world use where there would be more CCF to absorb the vibrations laterally - that could penalize some of the materials (or, thinner versions of like materials) disproportionately - but at least the test is fair in the consistency.

If Justin were to replicate this test, but instead use it to compare different CCF's - including different brand name CCF and several generic CCF - I'm confident you'd see a pretty tight grouping pretty close to where the CCF's measured on this were. That's my point.

Unfortunately that's not what this test measured - but it's still a great test with some real eye-opening results.

Back on topic with the thread to benefit members rather than egos:

The REAL interesting takeaway on his test here is that these three options actually perform better than CCF -

• synthetic pillow stuffing
• Thinsulate
• Second Skin heatwave

I always suspected the thick felt-like material that you see behind lots of OEM car panels might be a better performer - I've heard it called "jute" so maybe it's exactly the same as Second Skin heatwave.

It's interesting that Second Skin doesn't advertise it as a vibration barrier, but does advertise it as a noise barrier - something that would also increase it's appeal to me, or any installer looking for an effective noise barrier.
It's similarly noteworthy that literally EVERY composite product (3/4" Sonic Barrier and thicker, Cascade VB2 and VB4, Second Skin's own Luxury Liner) ALL use CCF as the vibration barrier - and not one of the three above. That's cause for pause.

Especially in my personal case with trying to keep weight down in a car (and not a little - we're talking about 50 pounds of difference, in 100 sq.ft. of material... about the equivalent of removing a front seat!), I'd love to see the noise barrier effectiveness of these two options compared:

• CCF with 1/8" MLV
• Heatwave with 1/16" MLV

Unfortunately, like the old Tootsie Roll pop commercial (not to show my age) - the world may never know. It's data we don't have.

I can compare the expense:

• Generic 10mm (1/2") CCF can be found for about $1/sq.ft.
• Second Skin Heatwave comes in at just over $3/sq.ft (it's currently on sale though, just under $3).

I made the point above about how spending more money for name-brand CCF is foolish over generic CCF.
In this case, however, it seems there's a tangible benefit of Heatwave over CCF. Is it worth 3x the expense? Maybe. Shame it's not 1.5x the cost, or less.

I'd again wonder why it's not used in the composite products.
I'd again worry about the validity and potential flaws in the one single test that shows it to perform superior in a vibration barrier application.
I'd wish that there were more tests that show it.
I'd wish that SecondSkin would put up a plot of noise-reduction-by-frequency, like all the MLV OEM's do (and their alternative competitors, like this one which unfortunately performs lesser-than MLV).

Those things would make the decision easier.
In absence of data, or experimentation, the safest option is usually the tried-and-true traditional option - CCF.

I may have a reasonable way to do this experiment myself - what I don't currently have is 1/16" MLV. Maybe I'll pick some up just for this, to compare to 1/8", and do the comparison myself.

I'm confused by your statement of not many CCF's were used....


Second Skin Overkill is CCF
RAAM ensolite is another CCF I believe
SDS neoprene is a CCF
Luxury liner pro is a CCF and MLV just coupled at the factory

The two you said are CCF (Sonic Barrier) are actually open cell by PS's descriptions...

"Sonic Barrier 1/2" Acoustic Sound Damping Foam with PSA 18" x 24"The Sonic Barrier 1/2" acoustic damping foam is a precisely engineered material that offers optimum absorption for its thickness. The material features our exclusive embossed surface finish that helps to trap acoustic energy and improve high frequency performance. This finish is applied to an acoustic-grade open-cell polyether foam,"

I believe what this does show is that, like you have stated, CCF is kind of an afterthought for most. It actually matters or it is a waste of money. It needs to be as soft as possible, much like pillow stuffing (but that isn't good for car use and is why we do use CCF).

Too stiff, and it gets to be pointless (or even worse) as you get to the point where you would have been better off just hanging the MLV by itself with no decoupler.

It also shows a pretty wide range of CCF products from 970hz to 1550hz. No where near as good as some, but still a fairly wide range.


This also is similar to CLD tile choice matters. Some are good, some aren't.

MLV is the same as not many actually make this.

3m ACOUSTIC thinsulate works well and I used this quite a bit in my truck, but it must be the acoustic thinsulate.

I'll have to check out the acoustic thinsulate as well, do a little cost-compare... and add it to my noise-block compare to see if it compares to the HeatWave in that way as well.
The SecondSkin Heatwave obviously is meant as a thermal insulator as well, and that also has me thinking: It adds an interesting other consideration.

Being in Buffalo NY, it's already cold here, have to run the heat in the car, turn on the heated seats, etc. Heated seats alone help with not running the heat full-blast, but it's usually still a constant in the winter. It could be an extra benefit if either of these serves as a real thermal insulator, that would allow you to turn that interior fan down.

I've even speculated on buying a bunch of heated seat kits, and installing those in the floor just below the carpet, to create an inexpensive electric radiant-heat, to also allow that benefit, but that's just another thought to the end on "reduce fan noise" with cold weather.

Anyway - that's off topic with this particular thread, but I'm glad you mentioned it.

What's your experience with the noise blocking aspect of it? I don't suppose you installed in stages, so that you might have actually had some time to drive around with just damping/thinsulate?

why ccf? usually thin enough to fit between vibrating panels and decouple them. it's aftermarket, where automotive manufacturers haven't already accommodated for pillow/jute insulation/space.

why ccf? closed cell foam is supposed to help in high-moisture environments. usual use is in the dry portions of the car, so this benefit is sorta moot.

1/8" hmf (hydrophobic melamine foam) seems to be softer than ccf but also moisture-rejecting. i don't know how well it'd work in these decoupling cases. second-skin sells 1/2" thick as mega-zorb heat insulation, i'm sure others have it as well.

buying blocks of magic eraser (hmf) and cutting it up into strategic spots might work as well to decouple things.

i've lucked out in my car, i've got space behind panels for deadener. i just stick ccf to mlv/sheet-lead 100% and place it.

FYI - I got my hands on 12"x12" samples of 0.75 lb and 1.5 lb mass loaded vinyl.
I have lots of 10mm closed cell foam, and I have a section of Honda OEM Jute that isn't Heatwave but is very similar.

That will allow me to compare the relative noise blocking effectiveness of:

• MLV with a 10mm closed cell foam layer
• half-weight MLV with a 10mm Jute barrier.

At some point over the winter, I'll build basically a bandpass box, where the center divider will have a 10" square or circle cut from it, with a frame to hold the samples and decouplers.
On one end, will be an opening to seal the mic against to do a REW sweep, so we can see the results by frequency, since that's of course a necessary factor.
On the other end, I'll have an opening to send sound into - I'll probably just stand this whole rig on top of an existing test cabinet that I have for a 6.5" woofer.

I'm personally interested if the thinner/lighter MLV and Jute/Heatwave can be used for weight saving purposes, yet be similarly effective.
...or based on Justin's results, actually seems likely to outperform it between 67hz and 321hz. Possibly even across the whole spectrum, when used in combination.

If you think about tire noise and road noise - which would be why people want to install product beyond simple CLD that stops panel vibrations but doesn't block road noise - lots of it occurs right in that range:
(graphic from a Michelin road noise study whitepaper)
Attachment 14704
That might be exactly why OEMs use jute products (which are similar to heatwave - though there's generic recycled cotton Jute products out there too) rather than CCF in luxury cars.

So right now, I'm busy setting up a windshield/side-windows/A-pillars in my basement lab for some imaging experiments (or rather, near the PC in the open space where my fiancee is not so pleased :lol: ), but this is an objective, measurable, much simpler experiment that Justin's results definitely imply some plausibility.
It's definitely an answer that I want to know the answer to before spring, so it's being added to the list.

We'll see where CCF really stands. :cool:
Especially since the gauntlet was so arrogantly thrown. :wink:
In all my years moderating audio forums, I've had low tolerance for obnoxious trolls - but this is an answer that I do want to have regardless.

i don't have any factory jute in my doors. my floorboards are lined with 2-3" thick factory jute below the carpet, factory CLD in strategic places. there's a thick rubber+jute under the front footwells.

i suspect the jute will have an impact as a sound barrier but it won't be as good as mlv. however, it likely weighs less too which helps fuel economy numbers. it also probably checks some environmental/recycled boxes, which is good as well. so there's probably a bunch of business-related reasons to use it over other competing products.

i suspect ccf isn't thick enough to have an impact on anything but high frequencies. its use case is generally decoupling though, not a sound barrier nor deadener.

i think the SDS folks also extolled virtues of the pillow insulation as sound barrier, but i don't know how effective it is when compressed flat (like what happens adding it to doors where there's no space for it)

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Originally Posted by nadams5755

i suspect the jute will have an impact as a sound barrier but it won't be as good as mlv.

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I'm not sure - it is fundamentally different.
But bear in mind, 1/16" MLV is more than half the effectiveness of 1/8" MLV.

There's also the consideration that jute weighs more than CCF. I'll have to compare that on the postal scale too. I'm sure that the weight difference between jute and CCF won't equal 1/16" of MLV, though.

Quote:

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Originally Posted by nadams5755

i think the SDS folks also extolled virtues of the pillow insulation as sound barrier, but i don't know how effective it is when compressed flat (like what happens adding it to doors where there's no space for it)

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I agree - the more you compress something, the more rigid it becomes... the more rigid something becomes, the higher the resonant frequency.
Is it likely that Justin's results are another way of arriving at a resonance of a combination of materials?

I'm thinking you are right - if I were a betting man, I'd think if you compressed pillow stuffing to the density of jute, you'd basically have jute. But there's other organic material in jute that apparently give it different properties, I'm sure heatwave isn't simply jute either...
I'm just going to do this as the most basic comparison.
Maybe I'll be ambitious and see if they will send me a heatwave sample for this, too, to see how it compares to OEM.


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Quote:

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Originally Posted by geolemon

.....
We'll see where CCF really stands. :cool:
Especially since the gauntlet was so arrogantly thrown. :wink:
In all my years moderating audio forums, I've had low tolerance for obnoxious trolls - but this is an answer that I do want to have regardless.

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Hi, since I am a nooby here I was wondering whether you were able to perform your tests and posted them somewhere else?
I hope you had the time and were successful. 🤞

I haven't, and my apologies for that.

I do have two squares and a concept for a test rig, but with my position i found myself leading QA for an IT project tied to a government mandate that we engaged a consultant vendor for [to implement before the July deadline] to avoid potentially millions in fines... while also enduring the data sharing aspect of this new national network didn't risk the company millions in lawsuits.

Even with a global QA staff able to work nearly around the clock, we couldn't overcome a vendor who overpromised and underdelivered, and my whole team has been overwhelmed.

You can see the progress on my own install has been just as handicapped.

But I'm glad you reminded me -
Worst case, if push comes to shove, my own car will get to the point where I have to make this decision.

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No need to apologize, getting out of this spot between a rock and a hard place has priority. Good luck and success with your project!

geolemon, if you do get some results with your experiments, I'd love to hear about it too!

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Originally Posted by Justin Zazzi

geolemon, if you do get some results with your experiments, I'd love to hear about it too!

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No time yet, but I've purchased two MLV in the two thicknesses, and I'm sitting on piles of MDF and scraps, and have my own install actively going on, so there's no physical barrier to building a rig for sure. Just time constraints.

I haven't built anything yet, but here's my test rig I've worked up in my head:

Two boxes. Really three if you count the one a test speaker will be in.

Attachment 16124

Box 1: will have my calibrated mic held inside. Shouldn't really need to be totally enclosed but we'll see. Will have a 6" hole or so in the other end.

Box 2: basically will have a 6" hole in each end. One end will be used to sandwich a piece of MLV between box 1 and 2, boxes screwed together to hold it tight but make it easy to swap MLV.

Box 3: a test speaker (probably a 3") firing into the 6" hole, screwed tight to box 2. I have a bunch of knocked-up test boxes that I don't care about screwing through.

That way, all the sound will be contained in box 2 - other than sound leaking through the MLV.

I'll do sweeps with REW.

Quote:

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Originally Posted by geolemon

No time yet, but I've purchased two MLV in the two thicknesses, and I'm sitting on piles of MDF and scraps, and have my own install actively going on, so there's no physical barrier to building a rig for sure. Just time constraints.

I haven't built anything yet, but here's my test rig I've worked up in my head:

Two boxes. Really three if you count the one a test speaker will be in.

Attachment 16124

Box 1: will have my calibrated mic held inside. Shouldn't really need to be totally enclosed but we'll see. Will have a 6" hole or so in the other end.

Box 2: basically will have a 6" hole in each end. One end will be used to sandwich a piece of MLV between box 1 and 2, boxes screwed together to hold it tight but make it easy to swap MLV.

Box 3: a test speaker (probably a 3") firing into the 6" hole, screwed tight to box 2. I have a bunch of knocked-up test boxes that I don't care about screwing through.

That way, all the sound will be contained in box 2 - other than sound leaking through the MLV.

I'll do sweeps with REW.

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Wouldn't that just turn the mlv into a passive radiator? Wouldn't it be better to have the center enclosure vented to atmosphere?

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Originally Posted by ckirocz28

Wouldn't that just turn the mlv into a passive radiator? Wouldn't it be better to have the center enclosure vented to atmosphere?

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I don't think it would. It's not going to be able to move, and it doesn't flex.

All that will happen is we'll measure how much sound permeates and see that on a response plot.

If the center cabinet is open to the outside, then the sound will be able to escape as well, and potentially be picked up by the mic.
In that case, I'd HAVE to seal that mic chamber.

The goal is to have all the sound coming to the mic, only having the path of "through the MLV".

You never know - might even have to do more than just MDF, but hopefully will be good enough for an A/B test.

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