Noise, Vibration, Harshness (NVH) infoPosted by daniel-crotty on March 23, 2022 at 5:06 pm
I have watched a few of the Vids of Aptera being driven. Almost everyone I know was disappointed in the noise level. That, I pointed out, was a beta, etc. version being driven with windows down. Those had a loud electric motor whirl. Blah, blah.
Still, it does raise the point. One of the big selling points for me is/was how quiet people are saying it is.
I just finished watching a new Sandy Monro Vid on a Tesla and they took it for a Test drive. That was quiet. I expect Aptera to do as well if not better.
So! I do want to hear what other are thinking. It would be nice to get some Db levels stats. Yes, it is hard to do now since we do not have a production model yet. Especially, let’s see a YouTube video of a test drive and hear it in action.
- 18 Replies
- MemberMarch 23, 2022 at 5:45 pm
In all those videos with the test drives. The windows where down I believe.
- ModeratorMarch 23, 2022 at 6:46 pm
Where does noise come from vis-a-vis a typical Tesla? A thought experiment, based on no knowledge. (Always risky.)
– motors. Front pair, in-wheel, in separate housing, should be quieter. Rear one in AWD, harder to see how well it can be isolated, but I’d guess equivalent to a Tesla.
– drive train gears. In-wheel motors don’t have those, or at least not many. Advantage Aptera.
– tires. Similar to motors, but pretty specific to tire vendor. For my current ride, winter tires are by far the biggest noise source.
– door, window, and hatch seal leaks. Quality question. Sandy Munro’s Plaid had a badly done seal that drove him nuts. I can imagine this is harder than non-professionals (like me) would think.
– piece rattles. Another quality question. Simpler and lighter details should be better than most.
– exterior surface turbulence. Aptera should perform better, between streamlines and composite.
Overall, it seems to me that it will depend on quality design and assembly, but there is no reason my Aptera should not be quieter than my Model Y.
- MemberMarch 23, 2022 at 9:32 pm
Actually, it was an alpha: At present there’s only one beta and it’s little more than a test rig.
It’s actually not hard – it’s IMPOSSIBLE to release any sort of information about a production-quality vehicle that doesn’t exist. It would be akin to standing inside the framing of an unfinished house and talking about how drafty it’s not going to be.
Did you note that Sandy was astonished by how much quieter the NEW Model 3 was than the one his company bought a few years ago? The addition of acoustic glazing in the doors makes a HUGE difference.
- MemberMarch 25, 2022 at 3:48 pm
Just a few months ago we were talking about pedestrian safety noise makers, now were talking about how quiet we want it. One thing I know is, don’t bother installing an AM radio. The motor EF and the regen braking EF is noisy on an AM radio, at least in my Prius. For myself I hope the Aptera is not too quiet. I need something to keep me awake that’s not music. Talk radio is usually on AM, and I don’t carry a cell phone.
- MemberMarch 25, 2022 at 4:39 pm
Honeycomb composite construction, motors outboard, most aerodynamic shape possible. There is no way that the Aptera is not the quietest car available.
- MemberMarch 25, 2022 at 9:47 pm
Watch the Beta test ride video, noise problems seem to be solved.
- MemberMarch 26, 2022 at 2:48 pm
Thanks Oz for the offer. I loved my 62 VW bug with no gas gauge and only 36 horsepower, but we would need a recording of the outside to help warn pedestrians we are coming.
Tim, There is one way to make the Aptera NOT the quietest vehicle around, just put some knobby tires on it. I just replaced a summer tire on my Prius with an all season redial tire and now its as loud as it was before I replace the front worn out wheel bearing. Imagine what it would sound like with snow tires on dry pavement.
- MemberMarch 26, 2022 at 4:07 pm
LEAVE MY QUIET car alone or, make it even more quiet! I don’t even want the noise to alert people I’m coming. That extra noise is a health hazard to my ears.
I’m ok with giving the people a watch that beeps or vibrates if a car is coming. A little signal to the watch that intensifies the closer you are to the running car.
If you really want noise, do what Hyundai did (or so I read). They play engine sounds over the speaker on a Veloster. At least that way its only your own hearing that is being ruined.
Quiet is a HUGE benefit of Aptera. You can put a glass-pack muffler on it, but it would not make it any quieter, or louder.
Imagine! Sitting on a NY City street and hear the children playing.
If I could just get a legal limit the volume on the Sound systems … !
Now, about those horns 🙂
- MemberMarch 26, 2022 at 7:18 pm
The audio you hear on a YouTube video is vastly different to the actual sound inside a moving EV. Yes, they are absolutely silent – when they are not moving. The lack of background engine noise allows you to hear every other sound they make, though – like the fans and pumps. You can hear people talking in vehicles next to you at stoplights. When they’re rolling, however, you do hear road and wind noise much more clearly – again, because there’s no engine noise and vibration to mask the sound. Manufacturers have to put a lot of effort into damping those sound to an acceptable level. Usually you hear a slight whine when accelerating and when braking but, other than that, there’s very little sound generated by electric motors.
Because Aptera is so “slippery” we probably won’t have to deal with much wind noise and, because the front wheels are outside the body of the vehicle, a lot of the tire noise will dissipate into the airstream instead of resonating in a wheel well.
“Quietness” is a relative concept. All EVs are more quiet than ICEs, but not all EVs are equally quiet: I’ve found the Ford Mach-e to be quite noisy while the Kia EV6 was nearly silent in comparison. A 2018 Tesla Model 3 is significantly noisier than a 2021 Model 3. One thing of which I’m certain, though, is that Aptera will make their vehicle as quiet as they can.
- MemberMarch 27, 2022 at 1:37 pm
Do you think an AWD version of the Aptera would be noisier because the rear wheel motor is not outside the body?
- MemberMarch 27, 2022 at 2:40 pm
Doubtful. Motors are generally pretty quiet. The road noise should be about the same, hard to see how the presence of a motor would change the road noise except for maybe changing the resonant frequency.
I have a 2019 Model 3 and the wind noise is pretty terrible, my old Volt was much quieter. I think Tesla’s problem is the use of frameless windows, the Volt had conventional window frames. The top half of the Aptera window is fixed which should help, the question is if the seal between the movable part of the window and the fixed part of the window will be tight.
- MemberMay 2, 2022 at 5:39 pm
What is Aptera doing to address noise, vibration and harshness, NVH? What sound deadening materials will be used and where? How will the harmonics of the hub motors (unsprung weight) and ride quality (suspension) be addressed? Will it have double pain glass to reduce noise? I own a Tesla M3 and it’s not the quietest, most comfortable car I have ever driven. Also, what are the specifications of the tires? What manufacturer will be used? I assume a flat repair kit will be included.
- MemberMay 2, 2022 at 6:21 pm
They claim the monocoque composite body is inherently quiet. In the discussion video about the wheelpants, they mentioned supports in the outside panel on the front wheels to reduce harmonic vibrations, so we know they’re thinking about it. The compound curves on the large structural components will also stiffen the body.
- MemberMay 2, 2022 at 11:59 pm
Much of the noise from an ICE vehicle is engine, tire, and air. All of these are significantly reduced by Aptera’s design. I can compare my 2001 Honda Insight that I drove for 15 years. It was relatively aerodynamic and had low rolling resistance tires. It was quiet enough that I was often unaware that I had reached 90+ mph on my interstate commute.
- MemberMay 3, 2022 at 7:32 am
I hope they are paying attention to it. I also have a Model 3 and the noise is really annoying. I previously had a Volt which ran around on little cat’s feet when it was in electric, when I got the Model 3 I was surprised by how loud it was. Tesla’s big mistake are the frameless windows, they always sound like a window is open. The top part of the Aptera’s windows are fixed but there is a lower window that rolls down, hopefully it won’t suffer from the same problems as Tesla. Newer Tesla’s have double pane glass and better seals which are supposed to help. Tesla also skimps on the sound deadening material, that’s something that’s cheap so there is no excuse not to put it in every place that needs it.
- MemberMay 3, 2022 at 7:49 am
You’re asking a lot of questions that won’t be answerable until the Delta development phase – and Aptera is currently in the Beta phase.
MOST of the acoustic materials used in metal-bodied vehicles is to stop “oil-canning” – the sound made by flexing panels of metal. It’s applied where needed – just watch a Sandy Munro tear-down video.
Munro has also spoken to the fear of hub motors as unsprung weight and the effect it does NOT have on vehicle ride, handling and performance.
Aptera’s opening door windows are relatively small and are NOT in an high-pressure area of the body where they will be buffeted by wind. Although I know the benefit of acoustic glass, it’s more than twice as thick as regular door glass and more than twice as heavy, requiring beefier, heavier mechanisms to move it.
Having compared a 2018 M3 with a 2022 M3 I can assure you that they are entirely different vehicles when it comes to passenger comfort: The 2022 seats are vastly more comfortable and supportive and the interior is, easily, twice as quiet.
Aptera rolls on 195/45 R16 LRR rubber – one assumes they’ll go with whichever tire they deem most suitable to the vehicle’s needs. Yes, most vehicles come with a flat repair kit nowadays – but they’re an inexpensive addition, if not provided by the manufacturer.
- ModeratorJune 15, 2022 at 8:49 pm
A fair amount of NVH engineering can be done in simulation and I presume that has been happening. “Delta” engineering is well underway, I believe, and that’s when it has to happen. (The public view is Alpha and Beta and should soon be Gamma, but it is a continuous and overlapping process.) Once Gammas start getting built, fixes might be identified physically. I’d guess that minor fixes to Deltas (and Paradigms) might even be needed. No one said it would be easy.