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Comment by Turskarama | Hacker News Reader

With modern (unmodified) cars a lot of the time tyre noise is actually more significant than engine noise, so a switch to electric by itself won't do it.

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It depends, rolling noise is more important at high speed, but engine noise is more important at slow speeds. If you are next to a highway, it probably won't make a difference, but if you live in a city with a lot of slow traffic, it will.

Also, mopeds, even unmodified ones are way too loud, especially for the speed they are going.

For sufficiently low speeds, yes. The crossover point is not high. Something like 30km/h .

Edit: Source https://www.researchgate.net/figure/Propulsion-noise-the-tyr...

30 km/h is the maximum speed allowed in many cities (and a growing number of them) and even in cities where 50 km/h is allowed, the average speed is apparently around 30 km/h when traffic is minimal (in France, according to [0]) and 15 km/h otherwise. I think it's safe to say that electric cars reduce noise in cities, in fact I can observe it every day myself from my house.

[0] https://www.francetvinfo.fr/replay-radio/le-vrai-du-faux/une...

That's why electric cars are required to emit an artificial noise when driving under 30 km/h to alert the visually impaired pedestrians. The Renault Zoe car makes a very strange noise, almost like an alien flying saucer from a 60s movie.

I understand the need for these noisemakers, having been startled a few times by electric cars moving at walking speeds as without a noisemaker, they are effectively silent.

But these weird spaceship noises, I hate them, and for some reason, dogs seem the hate them too. So unnatural. I much prefer more typical noise like white noise, like a fan running. I think that studies have shown that white noise is particularly good for that purpose as the source can be located easily.

The fan on the engine is often louder than they engine at low speeds.

Anecdotally, I live in a large apartment building in car-centric Southern California, and individual cars driving into the parking garage outside my window don’t disturb me (I like to sleep with the windows open). It’s the larger work vehicles that are the problem. The engines in big trucks (moving vans, trash trucks, construction equipment) are not tuned how personal autos are, for a variety of reasons.

For sure it's different with trucks. Sometimes that works in your favour, like when it's bin day and you forgot to take the bins out last night.

In general though I don't really know enough to know why they can't make commercial vehicles quieter. In my experience at least city buses manage to be relatively quiet.

I'm impressed that your buses are quiet. In SF, the city buses rattle my entire house when they pass by a half-block away. It's more "vibration" than "noise", but the whole house shakes and I hear clattering of little unbalanced objects in the cabinets and so on. In the last 5 years I've never experienced an earthquake that shook my house any more than the buses that pass by every 10 minutes.

By far the most annoyance is caused by illegally modified cars and bikes.

I live in the southern US and these things with modified exhausts are everywhere. There's no car inspection and no regulations are enforced. You can hear them at all hours of the day even if you live several blocks from a major road.

It honestly makes living here really annoying.

I live in Toronto and modified exhausts on motorcycles and cars are quite common and annoying. I don't see any enforcement action whatsoever.

This is often repeated here, but from where I’m sitting it self evidently isn’t true. I wonder if it could be because in the US there are so many automatic transmissions, and hearing high revs is relatively rare.. but most cars here are manual and high revs (in traffic) is common place

Only at speed.

At any speed you'd do on a road, even on suburban back roads tyre noise can match or exceed engine noise.

You didn't specify a speed, so I'm curious how fast are your suburban back roads? I've seen signs from the US that show 40mph speed limits on purely residential back streets which is already faster than I can drive on literally any street within my city.

Residential roads here are max 30km/h (18mph) but also often 20km/h (12mph). Slow enough that the EVs should produce less noise, even though both produce tire noise.

Out of curiosity, where are you driving that 20km/h is a common speed limit? Is it actually respected?

40km/h where I am. Below that is only seen in shared traffic areas (basically pedestrian areas where cars are allowed to pass through).

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