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The rise of fake engine noise

washingtonpost.com

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Re: The rise of fake engine noise

#141

Post by seanp2k2 »

jvanloov wrote: post #113
ars wrote: post #48

Am I the only one that associates loud noise with a weak engine? To me a powerful car just has an acceleration whine, and that's all. It's like a rocket exhaust: the "wilder" it is the weaker it is. A powerful, well tuned, rocket has a very sharp, and clean (i.e. not noisy) flame. Same with a car - if it's making a lot of noise, it's poorly tuned or designed.

A muffler restricts the exhaust and will lead to decreased power from the engine, even for properly tuned engines. Removing the muffler will remove the restriction in the exhaust and undo the power decrease, and also increase the noise.

This is not strictly true. Some engines work better with back-pressure, and removing or altering the exhaust without re-tuning usually loses power: http://www.formula1-dictionary.net/exhaust_road_perf.html

Re: The rise of fake engine noise

#142

Post by seanp2k2 »

exDM69 wrote: post #127
WalterBright wrote: post #96

Earlier quoted context omitted.

> Am I the only one that associates loud noise with a weak engine? Evidently you haven't been to a top fuel drag race! Most definitely, the more power, the more noise. Top fuel is so loud it is like being punched in the chest.

A top fuel racer is very loud because they have short, per-cylinder exhaust pipes and are powered by nitromethanol ("top fuel"), which burns so slowly that the fuel is still exploding when exiting the exhaust pipes. They are also ridiculously inefficient.

They're very efficient if you measure efficiency in terms of HP for engine weight, which is about all that matters in drag racing :)

Re: The rise of fake engine noise

#143

Post by gpvos »

Svip wrote: post #97
ferrari8608 wrote: post #94

Earlier quoted context omitted.

I just wonder, why does it have to be engine noise in particular? If I saw a Tesla, Leaf, Volt, etc. I wouldn't expect any engine or exhaust noise. Beeping, maybe.

Beeping? Like a lorry backing up? Even a low pitch beeping would become annoying pretty quickly. It should just be a sort of hum.

Lorries are switching to white noise instead of beeping, because humans hear that better. https://www.youtube.com/watch?v=fa28lIGuxq8

Re: The rise of fake engine noise

#144

Post by nitrogen »

ncza wrote: post #131
pcthrowaway wrote: post #119

Earlier quoted context omitted.

As a cyclist it's often helpful to be able to hear the sound made by cars moving across a street, for example, when approaching an intersection where perpendicular traffic should stop, but may not.

As a casual slow cyclist myself I already find it impossible to rely on audio too Mich, visuals are always needed. I have had several near collisions with other cyclists in the past who silently sneak up from behind or around corners. Afterwards I made sure to always look around before changing direction and treat every obscured corner as potential "devil puppet on a spring box" (no idea what they are called :) ). I…

"devil puppet on a spring box" (no idea what they are called :) ).

I believe this is what you mean: https://en.wikipedia.org/wiki/Jack-in-the-box

Re: The rise of fake engine noise

#145

Post by exDM69 »

seanp2k2 wrote: post #142
exDM69 wrote: post #127

Earlier quoted context omitted.

A top fuel racer is very loud because they have short, per-cylinder exhaust pipes and are powered by nitromethanol ("top fuel"), which burns so slowly that the fuel is still exploding when exiting the exhaust pipes. They are also ridiculously inefficient.

They're very efficient if you measure efficiency in terms of HP for engine weight, which is about all that matters in drag racing :)

Well sure, that's why they use nitromethanol (which is worse in kJ/kg than gasoline, but it contains an oxidizer) and ridiculous engines.

But "efficiency" in the context of engines usually means energy conversion efficiency. And power-to-weight ratio is what you mean.

Re: The rise of fake engine noise

#148

Post by cm2187 »

seanp2k2 wrote: post #139
cm2187 wrote: post #134

Electric cars do not pollute. We should force electric cars to emit some thick black smoke to ensure people do not get surprised! I don't know in what world these regulators live in, but in my world 80% of pedestrians are walking listening to an ipod/iphone/iwhatever. We already live in a society where pedestrians do not hear cars. But let's make sure cars remain a nuisance to anyone trying to sleep in a city!

The cars don't pollute, but odds are that the electricity they run on came from burning coal, and lithium batteries aren't exactly environmentally friendly to manufacture or recycle. The rare elements required for the electric motors and batteries aren't earth-friendly to mine or refine, either. But the car itself doesn't obviously emit any of this, so the public image it presents is great, hence their popularity. Fo…

I don't disagree but I wasn't making a statement about the eco-friendlyness of electric cars, rather about a law defeating a technological improvement. Cars are by a large margin the largest source of nuisance in a city and for two reasons: noise and pollution. Electric cars are solving both.

Re: The rise of fake engine noise

#149

Post by cm2187 »

jon-wood wrote: post #140
cm2187 wrote: post #134

Electric cars do not pollute. We should force electric cars to emit some thick black smoke to ensure people do not get surprised! I don't know in what world these regulators live in, but in my world 80% of pedestrians are walking listening to an ipod/iphone/iwhatever. We already live in a society where pedestrians do not hear cars. But let's make sure cars remain a nuisance to anyone trying to sleep in a city!

At least some of the remaining 20% are blind, and only have engine noise to work on when trying to work out if its safe for them to cross the road or not. I doubt the simulated engine noise has to be very loud to alert those people to the presence of a vehicle, but it does seem unreasonable to ask them to just take their chances, or listen out for the sound of tires rolling along tarmac.

There are many other dangers not making noise. Bikes for example. Blind or not, no one should rely on noise to decide whether it is safe to cross a street.

People got used to live with cars, it will be only a minuscule increment to get used to live with silent electric cars.

Re: The rise of fake engine noise

#150

Post by edpichler »

I think all of this is normal. Sound is also an interface, for it connects one world to another. As in software, if you change drastically any interface, the users will not like at the first. That's why great changes needs to be done in small portions. With the past of years, these fake sounds can disappear of the industry, after the users get used to electric cars.
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