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Discussion Starter · #1 ·
Guys, yesterday I was driving and I lowered the right back window all the way. As soon as I lowered, this weird acoustic booming sound could be heard. When I say, weird, I mean WEIRD! I was like a bass drum beating very fast perfectly in time. But, it was so loud and deep that it hurt my ears. I mean, it was overwhelming that I just couldn't stand it. It's hard to explain but it was very overwhelming and forceful. I lowerd the other back window and it go even worse! If I have all windows down, it doesn't do it nor if I have any combination of front windows adjusted. It was like something out of a moive sound effect. Maybe some one has experienced this? I don't know what the hell it is. If you have ever been outside and had the wind slap you right in the ear; that's exactly what it like but in a rhythmic fashion. Cheers, -C
 

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Cliff330i - Have you had the HK fix? If so, could the pressure relief between the cabin and trunk blocked by the repair materials, hence changing the acoustical characteristics of the cabin?

Just a thought
 

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Cliff330i said:
Guys, yesterday I was driving and I lowered the right back window all the way. As soon as I lowered, this weird acoustic booming sound could be heard. When I say, weird, I mean WEIRD! I was like a bass drum beating very fast perfectly in time. But, it was so loud and deep that it hurt my ears. I mean, it was overwhelming that I just couldn't stand it. It's hard to explain but it was very overwhelming and forceful. I lowerd the other back window and it go even worse! If I have all windows down, it doesn't do it nor if I have any combination of front windows adjusted. It was like something out of a moive sound effect. Maybe some one has experienced this? I don't know what the hell it is. If you have ever been outside and had the wind slap you right in the ear; that's exactly what it like but in a rhythmic fashion. Cheers, -C
Its a resonance... most cars I've had have this. Some combination of interior volume and roadspeed will create this. Just like a wind instrument, why it makes the noise.

Nothing to worry about.
 

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Discussion Starter · #9 ·
It's very interesting to me because I have never had this problem on any other car I have driven. Actually, it's more annoying than interesting but I love too many things about this car to be *****in' about stuff like this. Thanks for the insight gentlemen. :thumb:
 

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Odd. I've NEVER driven a car that didn't do this. That said, I have very sensitive ears. Above 10MPH, I'm comfortable with either ALL windows down or ALL windows up. Nothing in between.
 

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Cliff,

I have an '02 i also. I've notice exactly the same noise- very annoying. I've had it occur when I accidently hit the auto-down on the rear window instead of just cracking it open. The noise was so loud the first time it happened I thought I had a flat and the tire was coming apart. I'd guess it's some wierd resonance with the vehicle interior volume and the air passing by the window. It's a little annoying, but the car is so excellent otherwise, who cares:dunno: . Just use the air and leave the windows closed on the highway.

Mark
 

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Cliff330i said:
Guys, yesterday I was driving and I lowered the right back window all the way. As soon as I lowered, this weird acoustic booming sound could be heard. When I say, weird, I mean WEIRD! I was like a bass drum beating very fast perfectly in time. But, it was so loud and deep that it hurt my ears. I mean, it was overwhelming that I just couldn't stand it. It's hard to explain but it was very overwhelming and forceful. I lowerd the other back window and it go even worse! If I have all windows down, it doesn't do it nor if I have any combination of front windows adjusted. It was like something out of a moive sound effect. Maybe some one has experienced this? I don't know what the hell it is. If you have ever been outside and had the wind slap you right in the ear; that's exactly what it like but in a rhythmic fashion. Cheers, -C
Welcome to the wonderful world of acoustical physics.

Ed
 
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