Just another sound deadening thread

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13' CX-5 and 16' Mazda6 both Touring w/Tech/Bose
As title indicates I'm doing a project to help minimize exterior sound/improve interior sound.

I purchased Noico CLD (ei. Dynamat) to install inside of doors, front fenders, spare wheel well, hood, and hatch door. I'll cover roughly 50-70% of each area using the before/after tapping method to hear differences. Then as our budget allows in the future I will follow up with MLV in doors and floor (where I can get to). I sort of need help with how to remove each plastic cover over the rear wheels in the hatch. If anyone has links to photos that would be greatly appreciated.

Another thing I want to target is the stock weather stripping. I highly advise you guys keep them clean and supple. As well as their respective contact points along the painted door frame surfaces as to provide a good seal. A weak spot I noticed is they are attached via rivets. I'm looking into either sealing them with weather strip sealant or maybe adding additional weather stripping in some sections. I'll post photos and my findings as I go along.
 
I will be in the same boat with you when I finish doing my Tahoe. Just have to talk my wife into doing it on her CX-5.
With Tahoe, I noticed that CLD don't help sound insulation too much, if at all. What the stuff does, is helps with bass when listening to music, which I don't. I was also disappointed with the lack of "thumping" sound when closing the doors, very little change.
But wait until you put MLV in. The difference is amazing. The thump, the bass, and you can barely hear anything through that panel. I'm done with passenger side and the rear, about 50lbs of MLV in, and sometimes I need to crack-open passenger side window to equalize the sound, otherwise it seems like a deaf ear.
Make sure you do the complete floor and up the firewall, as much as you can reach.
I will also be taking the wheel well covers off, applying CLD and high-build rubberized coating on the inside, for tire noise.
Good luck, hope to learn few things from you when you're done and I'm about to begin with CX-5.
 
I was considering doing this myself, but I have changed my mind. I would like to shed some weight from the car, instead of adding more. My wheels are much heavier, then the 17"ers, added subwoofer, heavier component speakers. I put my music loud and I can't hear any outside noise. Base is good enough for me, no need to improve.
I'm even considering getting the CS exhaust, to shed more weight and getting better sound at the same time.
 
I will be in the same boat with you when I finish doing my Tahoe. Just have to talk my wife into doing it on her CX-5.
With Tahoe, I noticed that CLD don't help sound insulation too much, if at all. What the stuff does, is helps with bass when listening to music, which I don't. I was also disappointed with the lack of "thumping" sound when closing the doors, very little change.
But wait until you put MLV in. The difference is amazing. The thump, the bass, and you can barely hear anything through that panel. I'm done with passenger side and the rear, about 50lbs of MLV in, and sometimes I need to crack-open passenger side window to equalize the sound, otherwise it seems like a deaf ear.
Make sure you do the complete floor and up the firewall, as much as you can reach.
I will also be taking the wheel well covers off, applying CLD and high-build rubberized coating on the inside, for tire noise.
Good luck, hope to learn few things from you when you're done and I'm about to begin with CX-5.

CLD will def help on the CX-5 vs the Tahoe. Here's my take. Skyactivs Mazdas use good quality metal for the subframe hence the unusually high tensile strength of the roof (from collapsing) and good IIHS crash test results. They also put in quality chassis and suspension parts hence excellent handling. Then everything is covered by thin sheet metal. That's where the CLD comes in. Fortunately a little will go a long way. One of the tires on my Mazda6 blew out so I've got to get that fixed. Always something pushing back my budget dammit.

I was considering doing this myself, but I have changed my mind. I would like to shed some weight from the car, instead of adding more. My wheels are much heavier, then the 17"ers, added subwoofer, heavier component speakers. I put my music loud and I can't hear any outside noise. Base is good enough for me, no need to improve.
I'm even considering getting the CS exhaust, to shed more weight and getting better sound at the same time.

I looked at the CX-5 spare wheel well. There's lots of holes. Even if you take merely 5lbs of 50mil CLD (10 sq ft) to target those holes and solidify certain thin metal sections you could see improvements in your bass. As far as weight you can opt for a single CS exhaust for even lighter weight I think. Swapping to lighter wheels should help too but requires a higher investment.
 
Okay so I installed Noico's 50mil (CLD) Constrained Layer Dampener unto the outer skin of the four doors. There's metal beams glued unto the door set at 40 degree angle or so in there. I mainly targeted areas of open sheet metal. I created templates consisting of shapes (ex. 9 x 6 triangles and 2 x 10 rectangles) to fill surfaces I could get to. I covered edges with 4mil HVAC foil tape as to prevent any smell from leaking butyl plus it added a little thickness to the 50 mil sheet. I did not want to disconnect the power window/locks from the weather seal so they were connected the whole time which delayed my install being that they were in my way. Eventually of available flat surfaces I had access to, I covered roughly 35% with CLD in strategic locations. When I completed the driver door and closed it there's a considerably difference in tone when tapping it all through out its various sections. I added some CLD/Foil to some sections of the inner door which felt weak. Tapping the other three doors produced more of a higher pitch tink tink sound. I felt there was difference in traffic sound when driving near a motorcycle or large truck due to different frequency vibration on the doors. Road noise from tires and wind are still there of course and will be addressed later. Aprox. weight added to each door was 3-3.5 lbs. Weather was 110 degrees at 20% humidity and no smell in the CX-5.

When I have the funds and time I'll add foam and MLV unto the inner door which will provide the real sound stopping power. I will also attempt to install extra weather strips which I've ordered through Ebay.
 

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cx5-um, did you do an dB tests before and after? If not, please start now for a baseline before you add more.
There are a bunch of free apps for smartphones. If you don't have one maybe barrow a friends?
Just find a section of road you can test without much traffic. The free dB app I have lets you record highest point and average as well I think.
Giving us some hard numbers will help convince others if it is worth it, and might make you feel better about all the work you did.

I do have to ask, why the hell (literally) did you decide to do the job in the middle of summer. You just convinced me never to visit the state of AZ. It was 101 here yesterday, with 70%-80% humidity.
Just taking the dog out at 3am in the morning I was soaked in sweat.
 
cx5-um, did you do an dB tests before and after? If not, please start now for a baseline before you add more.
There are a bunch of free apps for smartphones. If you don't have one maybe barrow a friends?
Just find a section of road you can test without much traffic. The free dB app I have lets you record highest point and average as well I think.
Giving us some hard numbers will help convince others if it is worth it, and might make you feel better about all the work you did.

I do have to ask, why the hell (literally) did you decide to do the job in the middle of summer. You just convinced me never to visit the state of AZ. It was 101 here yesterday, with 70%-80% humidity.
Just taking the dog out at 3am in the morning I was soaked in sweat.

I wanted to add some CLD prior to going back home to San Diego for a few days. Once it gets to September we'll start getting down to 101 and lower humidity out here. 101 in dry desert heat is a cakewalk to me now lol. Another reason is you want the CLD tiles warm and pliable for application. I also got a good chance to see how they hold up in extreme heat while the door panels are accessed. I'd work for just a few minutes then went back inside my cool air conditioned home. I took lots of breaks lol.

I'll look into some dB apps. That said the CLD merely dampens the structural sound of the metal where its attached to. In my application there was probably a transfer in frequency range. Just to give folks some insight, I want the outer door skin (outside sheetmetal) to be more rigid (successful completed) yet okay to allow sound to pass through. The sound frequency range may have been altered a bit. This is where I'm at now on the CX-5. The inner door skin and door panel will utilize different material/s to do the actual sound blockage (pending upon funds).

Just for kicks I spent about 30 minutes last night applying CLD unto my Mazda6 trunk lid. 50% coverage. Trunk lid only and nothing else. I noticed 2 effects. First the bass from my sub hits deeper. Second there's more bass sweet spots in the cabin now meaning before while sitting in the driver seat you can hear more bass than sitting in the rear. Now there's more bass throughout the cabin. Well there's a 3rd effect too. The trunk lid closes with a more solid reassuring sound now. It use to feel and sound cheap when closing. I really should of used a dB app for some before/after findings.
 
I came across a promising remedy (not a 100% cure) for the CX-5 driver side mirror vibration issue a lot of us have. Basically the passenger mirror is stable but driver side vibrates increasingly as speed picks up. I've installed CLD (Dynamat) at 30-35% coverage inside the door. What really helped cut down the mirror vibration was after I installed an additional door weather strip. The mirror noticeably vibrates less. Driving 40mph on city streets on good pavement I can read signs on the mirror. The mirror doesn't vibrate much at that speed right now. Merging unto the freeway at 65-70 mph it seems the vibration was cut down noticeably as well. Its only when I bang on the plastic door panel while driving can I re-create the mirror vibration pre-treatment.

Theory: The CX-5 door sheet metal is thin to save weight. The driver side door has more controls = more wires/modules, ect. than the passenger side door. This would equate to more weight on the plastic door panel. Movement on the door panel transfers through the sheet metal and unto the mirror. Then there's the possibly of less sheet metal surface (as compared to the passenger side door) to accommodate the additional electronic controls and wires. Due to manufacturing costs, even Sport models may have the same sheet metal surface template in the driver side door sheet metal. Less sheet metal = less mass on the door which makes it easier to vibrate the mirrors. I've helped introduce stability against external and structural vibrations using CLD at 30-35% coverage inside the door. Specifically in the middle of the door. In theory one could target the section closer to the mirror for extra dampening.

The stock door weather strip (on this 2013 model) allows for the door to move ever so slightly which helps to contribute towards vibration. Noticeable mirror vibration. Adding an additional door weather strip meant more force is applied to closed the door now. The additional seal provides more surface contact to help stabilize the door from movement caused by wind and/or the car's structural vibration (engine, bumpy road, ect). The additional contact surface also creates a greater barrier for sound to pass through.

after1.jpgafter2.jpgafter3.jpgafter5.jpg

Edit: I noticed there's a TSB to fix the mirror shake. The dealer either replaces the mirror or makes some adjustments to its bolts or something.
 
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I added CLD tiles to the rear trunk area and also the rear quarter panels. There was I think one white OEM tile in each rear panel. Not surprisingly, adding additional tiles changed the tone of the panels when tapped. Waiting for my decoupling/insulation material to come in to be installed in the inner shell of the car. Crossing my fingers that this material can also lessen exterior sound allowing me to bypass having to use heavy MLV.

Rear Quarter Panel.jpg
rear CLD.jpg
 
When you finally decide to add MLV on top of your decoupler, you will forget about added mass and it's effects. It will be so day-and-night, you wouldn't believe you waited for so long.
Don't forget B-pillars, floors and foot wells. My Tahoe is quieter then equivalent Escalade now, and the work is still in progress.

Sent from my VIVO XL using Tapatalk
 
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I added the decouple material unto the doors.

Edmunds.com did a test on a 2.0l 2013 CX-5 model which measured 67db at 70mph. I'll use that as a rough baseline. (note: they measured lower dbs in later models. I guess Mazda added more deadening in later years).

Driving on a windy day through rough and smooth freeways and with the AC fan set (at 75%) going 70mph and using a simple app to measure dbs I got 70 dbs most of the way. I did however got down to 65 dbs when the road was smooth. The meter would spike like 5-8 dbs each time I hit a bump or drive over irregularities on the freeway.

My findings at this point suggest the best bang for buck in sound deadening is the floor and specifically the wheel wells. The particular decouple material I used is fire retardant treated cotton denim backed with foil. Its rated at NRC (Noise Reduction Coefficient) of 0.45 which means it absorbs up to 45% of sound. Pretty sure it does little for lower frequencies however. At home I placed a sheet to cover a dish washing machine and it was effective in minimizing the sounds from the spoons, plates, and glasses. Not much on the low freq's of the machine's motor. Placed a patch on top of my phone while playing music and it lowered the sound in about half.

When I had time I placed some of this material unto the rear hatch up to the wheel wells where this was little to no insulation. Just bare metal. I did not have time to test db's on the freeway post hatch install. I only have like an hour block of time on the weekends for this project in my busy schedule. Next up is to cover up the firewall and kick panels with this material.


Edit: not sure why my pics upload sideways?

door decouupler.jpg
decoupler hatch.jpg
hatch decouupler2.jpg
 
Just be careful using this material if you decide to proceed with MLV. Overall package might be too thick to fit under panels, particularly in doors. On my Tahoe project I gave up and used thin (less then 1/8") bubble wrap as decoupler, on both sides of MLV. Didn't notice any difference vs 1/8 CCF.
What is your material's thickness?

Sent from my VIVO XL using Tapatalk
 
Just be careful using this material if you decide to proceed with MLV. Overall package might be too thick to fit under panels, particularly in doors. On my Tahoe project I gave up and used thin (less then 1/8") bubble wrap as decoupler, on both sides of MLV. Didn't notice any difference vs 1/8 CCF.
What is your material's thickness?

Sent from my VIVO XL using Tapatalk

You are correct this stuff is thick at .375 inches.

Fortunately I really think the majority of the noise problem is in the floor/wheel wells. The rear hatch has zero heat/sound insulation. This material's thickness and foil backing helped back there. Oh and I had to add more CLD tiles underneath the spare tire. Wow the sheet metal back there was hot after a 40 mile trip. There's clearance to fit a layer of MLV. I now do see how a 1/8 foam | MLV | 1/8 foam sandwhich similar to what you did provides better fitment underneath all plastic panels. That's probably the ideal route.

On a side note the 4 doors are double weather sealed now. I also added some weather stripping above the headlights and the grill to help seal the hood from incoming air. I'm just copying measures other car manufacturers do to minimize wind noise. TBH the wind noise has gone down to where I can have conversations with people in back while driving 80 in the freeway without having the talk really loud. I've just about met my goal in reducing wind noise. I think the MLV stuff is icing on the cake. I just have to be careful with its weight as this cx-5 only has 155 HP. The majority of exterior sound is through the tires per the db app I used. I think MLV used on the wheel wells on floor will make the car quiet enough for us. Not sure if I'll use it on the doors for the CX-5. I may use it on the Mazda6 though.
 
Not sure what happened to my message, will start again.
I will be dropping plastic wheel well covers and installing CLDs to the inside of the fenders. Then maybe more CLDs on the inside of the covers, and will spray thick rubberized compound on top. Should help more with tire noise.

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Not sure what happened to my message, will start again.
I will be dropping plastic wheel well covers and installing CLDs to the inside of the fenders. Then maybe more CLDs on the inside of the covers, and will spray thick rubberized compound on top. Should help more with tire noise.

Sent from my VIVO XL using Tapatalk

FYI, the front fender wheel lining is plastic but I think the rear ones have a "felt" layer. I'm not sure if there's a plastic layer underneath it?
 
I got 36 sq ft of the Noico 80mm. Probably going to start Friday and see how far I get over the weekend. Doors first as my main goal is to improve the sound quality.
 
I got 36 sq ft of the Noico 80mm. Probably going to start Friday and see how far I get over the weekend. Doors first as my main goal is to improve the sound quality.

-Freys I would highly recommend you hold off until you get some decoupler and/or MLV. It will save you time as you'll do everything while the doors are opened. Otherwise if you can't wait read below-

Imho you don't need a whole lot Noico's coverage on the Outside door skin. Anywhere from 30-50% coverage in there is all you need to improve resonance. If anything, focus your coverage in the inner door skin side.

The inner door skin side is the inner metal door (facing the cabin) and the black plastic cover bolted on with 10mm bolts. I would not overlap sheets of Noico over BOTH just in case you need to access the outer door skin in the future. Instead I would ensure separate sheet pieces cover either the inner door skin or the black plastic cover.

Now had I did everything all over again I would do the above with Noico^ then come to a fork in the road. Do I (A) want to just minimize exterior sound to quieter levels or do (B)I want as much sound deadening possible? (A) I would've bought Ensolite stick and peel decoupler and placed it as a second layer on top of Noico to cover up the entire inner door side. (B) Followed up Noico and Ensolite with a third layer of MLV.

Ensolite: http://www.raamaudio.com/ensolite-i...ended-absolutely-the-best-foam-on-the-market/
 
The only part that I am wondering is the black panels in the doors. Thinking go under them and put the piece back on top. I don't have any extra money this summer to do anymore so this Noico is going to need to be enough.
 
The only part that I am wondering is the black panels in the doors. Thinking go under them and put the piece back on top. I don't have any extra money this summer to do anymore so this Noico is going to need to be enough.

Yeah you could do that.
 
The black covers on the inner door suck. Makes it so much more of a pain. Can't really just stick it over the hole. Wondering if it is even worth my time to try and put it on the back of the plastic? Stopping for the night before I start doing crap work.
 
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