Sound deadening mat.

[Babs3204]

So I ordered a slug of sound deadening mat on prime day and got out there this morning and pulled off all four door panels and covered the inside of the sheet metal and other existing structures with it. I'm not sure if it has a real tangible benefit so far in road noise reduction, but the car is black and I did notice immediately that it was less hot in the car when I went out to go pick up my daughter (105 outside) and the AC cooled down the interior very quickly, whereas the last time I went over her way in the same temperature, when I got there the AC was still struggling to cool the car down. I'm sorry, I didn't take any pictures, I would be horrible as a blogger. I just can't be bothered LOL. I've got work to do and stopping to take pictures just doesn't even occur to me. Anyway, if it's not too much of a giant pain, sometime in the next couple of weeks or so I'll see if I can put the remainder of the mat under the carpet and under the hood.

 

[Babs3204]

I guess I should add that my original secondary objective was to also get rid of or at least significantly lessen the hollow sound of the doors when opening and closing. Worked perfectly. They have a much more solid sound now. The doors are pretty much hollow inside with no insulation to speak of. There was a structural member running across the middle that was difficult to get to stop bonging, but I did manage to mitigate the sound some. I'll go back in soon since the panels are so easy to remove and hit them again on a cool morning. It was just too hot to continue messing with them.

 

[duncan-s]

I'll go back in soon since the panels are so easy to remove and hit them again on a cool morning.

Might you be persuaded to take pictures the second time around? You're under no obligation, but you know, "worth a thousand words" and all that.

 

[Babs3204]

Might you be persuaded to take pictures the second time around? You're under no obligation, but you know, "worth a thousand words" and all that.

Oh fiiiiiinnnnne..

 

[Babs3204]

Hey look it's a picture! I know, not the picture you were waiting for but a picture nonetheless. Today I went into the hatch area since I had to be there anyway to secure my rear dash cam which had come loose and pulled the flooring out which is super easy and the sheet metal below that is pretty bongy so I decided to throw a bit of sound deadening on that as well. I threw some on the area underneath the roll of mat there that already has some sort of compound on it as well and I think it has made at least a little bit of a difference Tomorrow I will take more pictures, because I got a good deal on upgraded speakers so tomorrow I'm going to pull all the door panels off again and install new speakers and will take pictures while I'm in there and perhaps even add a little more sound mat.

 

[MillerLF]

That's interesting mat! Great to hear about the improvements

 

[moapys]

Folks, as you are Googling for such things - if the phrase is not yet in your search - the best of these use "constrained layer technology": This sandwich approach - which envelops very dense interior material - represents some of the top tier products. FWIW

 

[Babs3204]

Well I did the front two speakers last night because I was impatient. I took a few pictures of the inside of the door panels but decided I didn't want to put down any new sound mat as it probably won't make a significant difference. I did the door panels when I was starting to get really hot outside so I probably would have taken a bit more time on some on the parts even though apparently you only have to attain around 40% coverage to see gains. I'm doing the back doors this morning and we'll take more pictures.

 

[Jerther]

Nice! I thought about doing this too. Although I don't think I'm going to stick the mats on the outside body, because anti-rust stuff is going there soon and it's probably going to prevent ice on the doors from melting during winter (my dad once did a repair on a front fender using spray urethane (not the best of ideas. That's my dad for ya...). Worked well, but in winter there was a very funny looking thick layer of ice on the repair )

Anyways, does it make a noticeable difference on outside noise when driving? How does it impact sound from the speakers?

 

[Babs3204]

Nice! I thought about doing this too. Although I don't think I'm going to stick the mats on the outside body, because anti-rust stuff is going there soon and it's probably going to prevent ice on the doors from melting during winter (my dad once did a repair on a front fender using spray urethane (not the best of ideas. That's my dad for ya...). Worked well, but in winter there was a very funny looking thick layer of ice on the repair )

Anyways, does it make a noticeable difference on outside noise when driving? How does it impact sound from the speakers?

It changed the timber of the music just slightly. Not so much that it sounded all that much different. I noticed a slight improvement in noise, but I'm not adventurous enough yet to start pulling panels and carpet to get to the wheel wells inside the car. I noticed a definite improvement in the sound when closing the door. Gone is the hollow, cheap car door sound. There seems to be an improvement in heat rejection as well. Not dramatic, but it seems better in the heat of the day.

 

[elmop]

There is, of course, the added unsprung weight. But I'm going to do the same given I have a bunch laying around in my garage.

 

[Bombastinator2]

TLDNR: sound deadening material factoids
A few years ago isolation computer cases were the rage and I looked into sound deadening material a lot.
The most efficient stuff is high mass. Soft rubber is common. The automotive industry noticed that recycled materials tend to be better because each time density changes, such as in glued or shredded materials, there is a chance for the vibration to turn into heat. Accoustically dead materials as a result tend to be cheap and heavy. Particle board (glued together sawdust) is unusually good for example. It’s why speaker enclosures are generally made from it. That recycled foam made of glued together chunks was actually created specifically as a sound deadening material by the auto industry. It’s use as carpet pad was secondary.
Electric cars require less sound deadening material than gas cars and tend to have less

 

[Patrik]

I have done the entire interior of my car and will do the wheel arches next. To get a good result you need to use a layer of 1-3mm butyl as base layer and on top of that 5-15mm of foam sound absorbing material.

 

[Babs3204]

TLDNR: sound deadening material factoids
A few years ago isolation computer cases were the rage and I looked into sound deadening material a lot.
The most efficient stuff is high mass. Soft rubber is common. The automotive industry noticed that recycled materials tend to be better because each time density changes, such as in glued or shredded materials, there is a chance for the vibration to turn into heat. Accoustically dead materials as a result tend to be cheap and heavy. Particle board (glued together sawdust) is unusually good for example. It’s why speaker enclosures are generally made from it. That recycled foam made of glued together chunks was actually created specifically as a sound deadening material by the auto industry. It’s use as carpet pad was secondary.
Electric cars require less sound deadening material than gas cars and tend to have less

Absolutely, my last EV and my Leaf are generally very quiet, but at least in the majority of the areas I drive in Sacramento, the roads are terrible with lots of small repairs and cracks and those black lines where they've filled in cracks. Some roads it's a cacophony of boom boom booms as that terrible surface echoes into the cabin. On a halfway decent smooth road it's a dream.

 

[Jerther]

Some roads it's a cacophony of boom boom booms

It's even worse with tire pressure at 41 psi

 

[Bombastinator2]

It's even worse with tire pressure at 41 psi

Which is probably why lower pressures are default. The wages of efficiency are often inconvenience.

 

[Babs3204]

It's even worse with tire pressure at 41 psi

Yah I guess that's true because that's exactly what psi I keep my tires at lol. I suppose I could take them down to Nissan spec. It surely doesn't make that much difference in range and I have plenty of that for my daily use as it is. I just got used to high psi when driving the Focus EV and was only getting about 65 miles out of it.

 

[Bombastinator2]

Yah I guess that's true because that's exactly what psi I keep my tires at lol. I suppose I could take them down to Nissan spec. It surely doesn't make that much difference in range and I have plenty of that for my daily use as it is. I just got used to high psi when driving the Focus EV and was only getting about 65 miles out of it.

Wow. Thats short. Would be even less in the winter. I can see doing everything possible to increase range.

 

[Bombastinator2]

Thinking about it, there are limitations on weight, and thickness. The move might be gluing that recycled foam carpet pad stuff. It doesn’t weigh much, will be helpful for thermal insulation, and is available by the yard. I’m not sure I’d trust super77 to glue it down with. That stuff degrades in a few years. Barge cement maybe? Something purpose designed?

 

[Babs3204]

Wow. Thats short. Would be even less in the winter. I can see doing everything possible to increase range.

Yah it's stated range was 75mi but I can't imagine how slow and careful I would have had to drive to ever get that range out of it. I would leave my house and not go above 25mph and get to the first traffic light less than a half mile away and more often than not it would already have subtracted a mile or even 2 of range from the energy "budget" display. I did really like the car for a long time, being my first EV (Focus Electric) and even managed to go two years on level one charging before finally installing level 2 which was a game changer in a car with that low of range. Ford is really good with sound insulation so I never noticed any audible penalty running high PSI, which I guess is why it never even occurred to me that it could be contributing to my current sound woes LOL.