My dad's new mercedes c-coupe has a bose system that has odd behavior. Wondering if any of you guys have heard of a system like this. The sound gets louder once you reach about 40 mph and then once you slow down at a light it gets really soft again. Anyone know why it does this?

 

High end cars do that, they automatically adjust the volume according to the ambient noise inside the car.

Some head units do that as well.

Look at the car's manual to turn the "feature" off.

 

heh, my girlfriend's new saturn has this... it is just becomming more prominent on cd players, you just notice it more on the mercedes because they are quiet on the inside already...

 

Thanks. I'll check that out.

 

It is called auto loudness adjustment, it automatically raises the volume of the music to compensate for road noise at higher speeds.

 

thats what it is supposed to due to compensate for road noise at higher and lower speeds and my advice is o get rid of the BOSE system any pro installer will tell you the same because you cant work on them you can upgarde you just replace it when it breaks or you just get a whole new system now.
each speaker has it own amp when the speaker blows and it will blow you have to replace both speaker and amp for a top end price when you could just get a sick sytem to start.

 

Actually may of the new Bose systems are 4 ohm drivers with external amps, not like in the older days when they had a 1 ohm driver with an amp attached to it. At the shop I work, we hooked a nice amp, such as a JL3004 in an 02 Escalade or Alpine MRVF307 into a SLK320 and the factory Bose speakers sounded to much better.