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Mercedes-Benz pre-safe sound

mercedesbenzofnatick.com

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Re: Mercedes-Benz pre-safe sound

#31

Post by coke12 »

ChickeNES wrote: post #21
taylorlapeyre wrote: post #4

I lost most of my hearing in my left ear in a head-on collision with a drunk driver. No other injuries. The audiologist said that my eardrum was in the kind of state you usually only see in battlefields from exposure to large explosions. People are always surprised when I tell them this was my only injury, and as a result I've always wondered how common this type of injury is with vehicle collisions. This is the firs…

There was a blogpost I read a few years back written by someone who damaged their hearing after dropping a porcelain toilet lid. They actually ran some back-of-the-envelope calculations to estimate the decibel level, I recall it being shockingly high.

There was a pretty good HN comment thread about it: https://news.ycombinator.com/item?id=16723099

From the linked thread:

""" 5. The stupid toilet bowl lid only fell about 8 inches. How could it damage my hearing so badly? I looked up the speed of sound in ceramic, divided by the length of the toilet bowl lid (and divided by 2 since the fundamental vibration is a half wavelength). This predicts 3.5 kHz.

6. This frequency is in the audible range. Using the short dimension of the toilet bowl predicts another (higher) frequency. The toilet bowl lid probably resonated at both those frequencies and their harmonics, putting all the energy into just those specific wavelengths.

7. The toilet bowl lid was not chipped or damaged, so the impact energy went mainly into sound (& internal heat) Maybe like half the impact energy went into sound energy. This lid was concave up like an antenna, near my face when it hit, focusing the energy into my face.

8. The energy travels into your inner ear and the cochlea. The pressure wave is strongest at some distance down the cochlea depending on frequency. Since the toilet bowl lid put all the energy into SPECIFIC FREQUENCIES, it was concentrated onto specific spots in the cochlea.

9. Apparently, this concentration of energy was enough to damage the hairs -- to bend them over like trampled grass -- and I was concerned it could be permanent. My hearing was only slightly better the next morning. It was like everybody was still talking at me through kazoos. """

Fascinating. Be careful around dropping shatter-proof ceramics, I suppose!

Re: Mercedes-Benz pre-safe sound

#32

Post by outworlder »

CaliforniaKarl wrote: post #6

I think this should be marked [2015], as the video included on the site was uploaded in 2015. But still, this is really cool! I also didn't know that the ear has a "self-defense" mechanism against loud noise. I wonder how that mechanism interacts with things like headphone audio being played at high volumes. Does the mechanism eventually wear out? How does that affect people who do sound effects/mixing/mastering for…

> Does the mechanism eventually wear out?

I hope not, because I have been able to control the muscle voluntarily and it is still works after almost four decades.

It doesn't go off by itself all the time though. It's more for sudden loud noise, I don't think it works at all for sustained loud noises.

Re: Mercedes-Benz pre-safe sound

#33

Post by chongli »

ChickeNES wrote: post #21
taylorlapeyre wrote: post #4

I lost most of my hearing in my left ear in a head-on collision with a drunk driver. No other injuries. The audiologist said that my eardrum was in the kind of state you usually only see in battlefields from exposure to large explosions. People are always surprised when I tell them this was my only injury, and as a result I've always wondered how common this type of injury is with vehicle collisions. This is the firs…

There was a blogpost I read a few years back written by someone who damaged their hearing after dropping a porcelain toilet lid. They actually ran some back-of-the-envelope calculations to estimate the decibel level, I recall it being shockingly high.

Porcelain toilet lids and the metal plates on weightlifting machines are among the most dangerous common objects when it comes to hearing damage.

I've heard of cases where the plates on the machine were stuck together with grease and the user had selected a much lighter weight than usual. A number of plates below the linchpin were all the way up by the bonds of the grease before slipping and falling back down. The metal on metal impact rings out like a bell, right next to the user's head (in the case of bench press). Really nasty!

Re: Mercedes-Benz pre-safe sound

#35

Post by MrEldritch »

outworlder wrote: post #32
CaliforniaKarl wrote: post #6

I think this should be marked [2015], as the video included on the site was uploaded in 2015. But still, this is really cool! I also didn't know that the ear has a "self-defense" mechanism against loud noise. I wonder how that mechanism interacts with things like headphone audio being played at high volumes. Does the mechanism eventually wear out? How does that affect people who do sound effects/mixing/mastering for…

> Does the mechanism eventually wear out? I hope not, because I have been able to control the muscle voluntarily and it is still works after almost four decades. It doesn't go off by itself all the time though. It's more for sudden loud noise, I don't think it works at all for sustained loud noises.

>I hope not, because I have been able to control the muscle voluntarily and it is still works after almost four decades.

Oh, is that how the brain rumblies thingy works? Huh, I never realized most people couldn't do that.

Re: Mercedes-Benz pre-safe sound

#36

Post by repiret »

trilila wrote: post #7

“Mercedes-Benz is constantly at the forefront of automotive safety technologies” - not really. Rear wheel drive, which is common in mb and bmw cars are a real danger in winter. Volvo claims, and seems to be, a safer and more at the forefront of safe driving choice.

In the past I have owned a BMW 330i and M Roadster, both rear wheel drive. I have never had another vehicle as easy to control on packed snow than either of those.

Re: Mercedes-Benz pre-safe sound

#38

Post by WrtCdEvrydy »

Swizec wrote: post #22
PaulHoule wrote: post #16

Earlier quoted context omitted.

Funny I was in a rollover in a Honda Fit and did not experience any injury or even pain. Some pyrotechnic device fired to tension the seatbelt but I only knew because I could smell it. I found myself hanging upside quite securely with my brain processing the strange sensation in being a place that was both highly familiar (my car) but entirely strange (being upside down.) I looked and saw that the back window had bro…

Modern cars are very safe. But luxury cars had pre-tensioners in the 80’s already. What do they have now that the rest of us will get in 2050?

Starting in 2019, you get backup cameras...

Luxury brands can actually stop you from going into a lane when a vehicle is there or minimizing the damage if you push it. Kinda like Tesla Autopilot but only when you're about to do something stupid.

Re: Mercedes-Benz pre-safe sound

#39

Post by tmacro »

MrEldritch wrote: post #35
outworlder wrote: post #32

Earlier quoted context omitted.

> Does the mechanism eventually wear out? I hope not, because I have been able to control the muscle voluntarily and it is still works after almost four decades. It doesn't go off by itself all the time though. It's more for sudden loud noise, I don't think it works at all for sustained loud noises.

>I hope not, because I have been able to control the muscle voluntarily and it is still works after almost four decades. Oh, is that how the brain rumblies thingy works? Huh, I never realized most people couldn't do that.

I realized it was rare, but I've never been able to explain what I'm doing to other people. Now I finally know!

Re: Mercedes-Benz pre-safe sound

#40

Post by rococode »

jedberg wrote: post #5

The Mercedes is known for being more expensive than most, but in most cases, it's worth it, not only for the luxury, but for the extreme attention to detail they put into safety. For example, when you get into one, it will adjust the tension of the seatbelt automatically to be ideal for each passenger. And of course this pink noise. And a ton of other little things that cost extra that most people will never notice.…

I was recently in the market and was impressed by the amount of safety features available in modern models (my old car being a 2011 model). In the luxury range everything had automatic braking for rear-end collision, back-up collision prevention, 360 camera, lane-keeping assist, etc.. (albeit often as part of a pricier package). I'm sure many other brands have similar features too.

A couple days after I got the new car, a kid ran out behind my car as I was backing out of a parking spot. It beeped and stopped me from backing up anymore. I think I would've reacted in time too, but it was quite reassuring to have the computer help out.

For me the most useful feature is the 360 camera, which is admittedly more convenience than safety. It starts beeping loudly before you bump into things, and shows you a top-down view of your surroundings on the screen. Super super super useful for squeezing into tight parking spots. Just this morning I had to get into a really tight spot, and I probably would've been pretty nervous without the camera haha.

It is a little scary though that the system has so much control over the car now. Makes you wonder what'll happen if it glitches while you're on the highway.

As an aside, I still haven't gotten used to the seatbelt pull which startles me every time, it's a pretty firm tug. The 2019 BMW models have that too.

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