teche21

I am having lot of road noise and wind noise problem in my new C300. And when I took it to the dealer they said it's normal wind noise and it is as designed. However after that I downloaded Decibel 10th app for iPhone and tested the noise level in my car and they were very bad. When i tested the AC system was off so that it can be as quite as possible in the car.

It would be great if other people on the forum with wind or road noise problem can also use such smartphone apps and post the readings in the thread.

My noise readings were Peak:92dB, Max:91dB, and Average 85dB.

Also here is a link showing average noise levels in many other cars: http://www.auto-decibel-db.com

Razzyh

Depends on a lot of factors.

Where was you holding/placing your phone.

What is the weather outside like

What speed did you test it at

What was the road conditions like

Etc.

teche21

So I held the phone in the center of the car between the front two seats, just above the center arm rest. Outside weather was clear with wind speed of 9mph. My wife was driving the car in between 70-75 mph and we were on I-5 in california, where road conditions were normal.

So, overall everything was normal, except the road and wind noise in the car.

cidtek

To be fair when comparing to other cars you have to use the same measuring equipment. Unless you have actually calibrated the app against an industry standard sound meter I wouldn't give it much cred.

arnold0523

I downloaded dB Volume on iPhone. Measured about 65dB when driving 50-75mph. Peaked 70dB at most. I can hear the wind noise (but maybe not that serious).

Please try using different software because I found out some sw are very sensitive to volume change and can easily peak at a high value. (I do not have a real dB meter so I can't say which one is accurate, but I believe mine is ok)

BenzC400

There is already a thread on this topic. I have used the Decibel 10th App and the Decibel Ultra (iPhone App). Decibel Ultra gives the most stable results. My reading with the decibel Ultra App were consistently 62-65 dB at 70 mph.

https://mbworld.org/forums/c-class-w...hlight=decibel

C400
19 inch wheels
Pirelli Sottozero run flat tires
DISTRONIC set to 70mph
Average condition highway

I found the Decibel 10th App to be overly sensitive. The reading bounces around quite a bit making it difficult to get a stable reading, so I don't know how valuable this will be. At its quietest, with no traffic nearby, my reading varied between 70-74 db at 70 mph. Sound dropped below 70 db between 60 and 65 mph. Passing traffic raised the noise level to the upper 70s db. Changes in pavement also caused significant swings in sound level.