Tesla M3 Cabin Noise

[anticowboyism]

I would be willing to bet tesla was trying to save weight. You can do thick glass and more sound deading but it all comes at a weight cost (and monetary cost of course too) You could do something like dynamat the vehicle and add the seals. To mat the whole car you would be looking at about ~60lbs of material.

This. I'm an acoustician and the best way to reduce cabin noise is to deaden the vibrations in the door panels with heavy insulation. The best stuff is asphalt based and would add substantial weight, reducing your mileage. Yes, the Model X is quieter, but also way heavier and less efficient.

Premium car manufacturers know this very well, which is why an Audi E-Tron has a curb weight of 5643 lbs, Model X is at 5185, and the Model 3 is at 3627. Heck my wife's Outback is 3902 lbs, and is much quieter than my M3. I don't think Subaru is considered a premium car, it's cheaper than mine, but heavier which makes it quieter.

 

[Nocturnal]

I really don't think that's the case. The engine in my previous ICE car wasn't really audible while cruising on the highway. The insulation between the wheels and the car body just isn't up to par for this price class IMO. I have also done a test drive in the Audi E-tron last week and it is MUCH quieter even though being an EV. This is something that Tesla needs to work on.

That said, it isn't unbearable or anything and shouldn't deter people from an otherwise great car.

It's a weight issue I suspect. Sound isolation = heavy/absorbing materials.

This. I'm an acoustician and the best way to reduce cabin noise is to deaden the vibrations in the door panels with heavy insulation. The best stuff is asphalt based and would add substantial weight, reducing your mileage. Yes, the Model X is quieter, but also way heavier and less efficient.

Premium car manufacturers know this very well, which is why an Audi E-Tron has a curb weight of 5643 lbs, Model X is at 5185, and the Model 3 is at 3627. Heck my wife's Outback is 3902 lbs, and is much quieter than my M3. I don't think Subaru is considered a premium car, it's cheaper than mine, but heavier which makes it quieter.

Yeah for sure. On my old trans am I added a ton of dynamat to the doors and trunk/wheel wells. I did it for my sterol system but it definitely reduced road noise by a large amount. ​

 

[M3_MikeH]

hi

I am going to take the delivery of a new Model 3 this week. It is the long range single motor. I have heard that the Model 3 has significant cabin / wind noise issue on highway. Just wanted to confirm if that is the case.

Regards
S

April 2019 Build, Delivered May 2019. M3 Dual Motor. No air noise. Most of my noise is road noise traveling on hard concrete with the 19" sport wheels. The tire pressure is so high and rubber hard that you are going to get more road noise than from a softer tire and smaller wheel

 

[john85775]

April 2019 Build, Delivered May 2019. M3 Dual Motor. No air noise. Most of my noise is road noise traveling on hard concrete with the 19" sport wheels. The tire pressure is so high and rubber hard that you are going to get more road noise than from a softer tire and smaller wheel

This. Here are the common results when comparing the 18" Aeros with the 19" Sport wheels: at speed, a 4db difference in noise. That's like hearing the noise twice as loud to your ear:

From this YouTube video:

 

[cab]

This. Here are the common results when comparing the 18" Aeros with the 19" Sport wheels: at speed, a 4db difference in noise. That's like hearing the noise twice as loud to your ear:

View attachment 432719

From this YouTube video:

Good post and impressive delta. Of course, I'm sure 75% of it is the tire choice vs. the tire/rim size making up that delta, but great info nonetheless.

 

[KenC]

Wow, you can really hear the difference in that video.

 

[Webeevdrivers]

Unsure of the source:

For whatever reason the Eplus Leaf is quite a bit quieter than the regular Leaf. Tires? Additional road clearance? Who knows. It is quite s bit quieter than the 3 though. Having said that although road noise was more audible during our model 3 Tesla drives their didn’t seem to be more wind noise. Not sure what factors affect that.

 

[Magnets!]

Doesn't sound twice as loud to me. Db scale is widely misunderstood due to difference between perceived loudness and sound pressure.
Were the tires the same model in the video and were the pressures identical?

 

[anticowboyism]

This. Here are the common results when comparing the 18" Aeros with the 19" Sport wheels: at speed, a 4db difference in noise. That's like hearing the noise twice as loud to your ear:

Doesn't sound twice as loud to me. Db scale is widely misunderstood due to difference between perceived loudness and sound pressure.

Yeah, the dB scale is definitely misunderstood, and is different than perceived loudness. While 3dB corresponds to a doubling of acoustic power, most acousticians agree that a change of 10dB sounds about "twice as loud". Another adage is that a change of 3dB is noticeable by most people, but 2dB is not.

So according to the measurements in the video, if accurate, means most people would notice that 19" sport tires are louder, but they wouldn't consider it twice as loud.

 

[Shizzrock]

Yeah, the dB scale is definitely misunderstood, and is different than perceived loudness. While 3dB corresponds to a doubling of acoustic power, most acousticians agree that a change of 10dB sounds about "twice as loud". Another adage is that a change of 3dB is noticeable by most people, but 2dB is not.

So according to the measurements in the video, if accurate, means most people would notice that 19" sport tires are louder, but they wouldn't consider it twice as loud.

I always post to clear this up, but 3dB is a doubling of power, which is a 10log scale. All of the measurements people use in these tests are SPL measurements, which use a 20log scale. So 6dB is an actual doubling of sound pressure, as in, when you double the pressure of sound waves to your ear drums expressed in pascals, it is expressed as a 6dB SPL increase. 10dB is commonly used as a perceived doubling of loudness, so that is correct. 3dB would be a small noticeable change, but technically 1dB is the smallest noticeable difference, hence why it is used in the scale.

Edit: An interesting fact is you actually need a tenfold increase in power to achieve a perceived doubling of loudness. So when people are looking for stereos, thinking a 50 watt amp is going to be twice as loud as a 25 watt amp, they will be disappointed. You would need a 250 watt amp to achieve twice the loudness.

 

[Magnets!]

This. I'm an acoustician and the best way to reduce cabin noise is to deaden the vibrations in the door panels with heavy insulation. The best stuff is asphalt based and would add substantial weight, reducing your mileage. Yes, the Model X is quieter, but also way heavier and less efficient.

Premium car manufacturers know this very well, which is why an Audi E-Tron has a curb weight of 5643 lbs, Model X is at 5185, and the Model 3 is at 3627. Heck my wife's Outback is 3902 lbs, and is much quieter than my M3. I don't think Subaru is considered a premium car, it's cheaper than mine, but heavier which makes it quieter.

There are numerous threads on the Tesla forums where people have lined their doors with dynamat or noico and it doesn't seem to make much difference in the noise.

 

[postersw]

I agree that my new M3 is definitely noisier than my 2014 Subaru Outback, even though it is twice the price (and my Outback is noisier than my BMW 328). Also the noise is road noise (actually tire noise) at freeway speeds (running tires as 40 psi). I find this pretty disappointing.

As an FYI, I installed the door gasket kits that are mentioned in other threads - this definitely reduced the higher frequencies in the tire noise, but left the lower frequency rumbles the same (that noise is probably being transmitted through the body as opposed to sneaking in past the door gaskets).

 

[Alketi]

I measured a 1dB difference before/after using one of the door gasket sets on Amazon. This was measured on the same three sections of highway at roughly 70MPH. Not all that impressive. I didn't capture the waveforms, but I agree with @postersw that the majority of road noise seems like it's lower frequency and as such is unaffected by adding door seals.

 

[UrsS]

Tire noise depends on the road surface. My Model 3 (early version VIN ...05641) was unbearably / headache noisy on rough asphalt roads. So I lathered sound deadening material wherever I could and got it so I could drive the car. It is still loud, but does not give me a headache any more.
I wish the Bridgestone Turanza Quiet Track were available, but they are not for the Model 3 18" wheels.

 

[cucubits]

The perceived noise also depends a lot on what you are used to. How silent was the car you had before the Model 3.

I've been on a drive test recently with the 3 and (depending on the road surface or course) up to about 60 - 65 there was more road noise than wind. Above that, it's pretty noisy.

To be honest, it sounded almost as loud as my wife's VW Beetle at most speeds. This is not good is you consider that the Beetle has the aerodynamics of a potato.

When/if I get a Model 3, I will plan on heavy soundproofing.

 

[cab]

There are numerous threads on the Tesla forums where people have lined their doors with dynamat or noico and it doesn't seem to make much difference in the noise.

Yep, so far no one really seems to have found any "smoking gun" with regard to sound deadening the 3. It is EASY to spend a lot of time and money installing deadener and blockers only to get middling results. I actually have a feeling the battery compartment (which should BLOCK a lot of road noise) actually acts like a bit of a drum on these cars. Not too many folks go to the trouble of pulling the front seats either to deaden the floors and cover them with MLV. As a bonus, the interior of the doors appears to be a lot more of a pain to access as well. Finally, all of these are just "chasing" noise and vibration that Tesla lets into the cabin and chassis. Most folks aren't going to be messing with stuff like bushing compliance or adding 50 lbs lead weights to surfaces to absorb vibration.

One idea would be to drive down a noisy stretch of road while someone else records video with their phone. They can move the phone around the cabin (i.e. near windshield, roof, doors/side windows/side mirrors, floor, etc. - repeat from rear seat area) and then play those videos back (from a PC - better speakers), listening for the loudest areas...the video part of the feed serves to record WHERE it was loudest. In my own cheesy version of this (while driving) the sound is typically loudest near the side mirrors. You can also do something similar as a solo driver by just laying the phone down while recording in an area, stop, change phone position, repeat.

A more sophisticated test would actually have a little mixer recording using 4 or 5 mics simultaneously (each positioned in different areas)...you know, like Tesla should have done!

 

[Zcd1]

I've been considering adding one of those trim pieces that covers the bottom of the parcel shelf, like this one:

Rear Trunk Soundproof Cotton Mat SoundProof Protector For Tesla Model 3 17-19 | eBay

Seems logical that the metal, unlined shelf transmits some noise from the trunk area, particularly with the big ventilation hole in the middle. This has slots to allow for ventilation/pressure relief, but I'd think would tamp down the noise some. I'm not a big fan of the price or the fact that it takes 2-4 weeks to ship from China, but I'm thinking about it...

The other obvious thing is the glass roof. With my previous Audi S6, even just having the moonroof sunshade open added to the noise level, so having MANY square feet of glass reflecting every sound all around the cabin of the 3 can't be helping. Power-retractable sunshades would be ideal, IMO, but I prolly wouldn't want to pay whatever that might cost, if it existed...

 

[KenC]

Bought one, and installed it. I can't tell if it helps, and no, I didn't do any pseudo-scientific testing. Just know that the piece I bought doesn't seem to completely cover the area near the back seats. Perhaps, one of the other eBay sellers has a better fit.

Besides that, I've added the door seals, the roof glass seal, the mesh screens for the roof, and as a whole, the car seems quieter. At least the frequency has changed. I have no idea which piece has helped the most, as they all probably help a tiny bit.

I've been considering adding one of those trim pieces that covers the bottom of the parcel shelf, like this one:

Rear Trunk Soundproof Cotton Mat SoundProof Protector For Tesla Model 3 17-19 | eBay

Seems logical that the metal, unlined shelf transmits some noise from the trunk area, particularly with the big ventilation hole in the middle. This has slots to allow for ventilation/pressure relief, but I'd think would tamp down the noise some. I'm not a big fan of the price or the fact that it takes 2-4 weeks to ship from China, but I'm thinking about it...

The other obvious thing is the glass roof. With my previous Audi S6, even just having the moonroof sunshade open added to the noise level, so having MANY square feet of glass reflecting every sound all around the cabin of the 3 can't be helping. Power-retractable sunshades would be ideal, IMO, but I prolly wouldn't want to pay whatever that might cost, if it existed...

 

[cab]

I've been considering adding one of those trim pieces that covers the bottom of the parcel shelf, like this one:

Rear Trunk Soundproof Cotton Mat SoundProof Protector For Tesla Model 3 17-19 | eBay

Seems logical that the metal, unlined shelf transmits some noise from the trunk area, particularly with the big ventilation hole in the middle. This has slots to allow for ventilation/pressure relief, but I'd think would tamp down the noise some. I'm not a big fan of the price or the fact that it takes 2-4 weeks to ship from China, but I'm thinking about it...

The other obvious thing is the glass roof. With my previous Audi S6, even just having the moonroof sunshade open added to the noise level, so having MANY square feet of glass reflecting every sound all around the cabin of the 3 can't be helping. Power-retractable sunshades would be ideal, IMO, but I prolly wouldn't want to pay whatever that might cost, if it existed...

If you can live w/o the view, you can put up a screen and put either 3M thinsulate or perhaps melamine foam between it and the glass.

 

[Mnuu]

I like the objectivity in these posts.

Before buying the Model 3 I did some light research and fell on forums from Tesla fanatics claiming the noise comes from the absence of the engine noise. I now know that I should have done better research. I own a Tesla Model 3 Dual LR, coming from a BMW 5 series. And whilst the Tesla is way more expensive, the sound is worse than in a... VW Golf.

I noticed when coming back from holidays that the noise was significantly lower than what I experienced while going. I thought first that I was getting used to it and that things were not that bad. Until I found the reason: when the tires are flatter, the db's go down significantly. I was thinking about leaving it that way, but unfortunately (and understandably) battery performance runs down as well...

So I guess we are stuck with lots of noise. For people owning a silent car and valuing low noise, the Tesla Model 3 might not be your best choice. Maybe wait for more options before switching to EV.