Eilers

Interesting. would you have any figures Glyn?

I ordered the Acoustic Glass option, and my car will as i understand it, be one of the first to get it. So there are no live reviews yet for this option.

My car is being built today, by current plans, it should be rolling off the assembly line at 20:38 (in 4 hrs from writing this!)

StanNH

I couldn't really tell the difference when I test drove the two variants back to back. In normal cruising, inside the cabin of the C300, I can not hear the sound of the engine. I couldn't hear the engine inside the C400 either. The cabin is quiet, with a low level of background road/tire noise, and whatever engine noise is present gets pretty much masked by that. With music in the background, which is how I always drive, engine sound is a total non-issue.

There is a real difference in the engine sounds at idle, from outside the car, and during acceleration ... where the 4 can sound a bit raspy opposed to the much deeper sound of the V6. The 6 is a smoother and more robust engine, but interior noise is not a serious issue with either model.

floridadriver

Zero difference in engine sound at cruise, it's absemt in both. The C400 on 19" and summer tires is noticeably louder. I'd say your suspension differences would be a bigger difference than engines for this car. In rapid acceleration and idle the sounds are very different, a v6 sounds more 'cool', no doubt. A v8 will be better.

I wouldn't base the difference in these two models on sound. Neither as quiet as a Buick or Lexus LS, but good for the class.

Speaking of acoustic glass, for anyone with a C class, do we get that in USA? I know there no option or mention, but the window should have code in stamp for it being laminated AG, or on top of window when roll it down a bit, would feel it have have a small a ridge on top, not rounded. ????

Glyn M Ruck

I was in a new 4 banger yesterday just received as a company car by a lady family member. It is pleasant & generally quiet but I'm always aware of the engine. Yes, we were climbing up & down hills as is the nature of our topography. On a short bit of freeway it was quiet but with usual Conti SC noise. The minute you make it work you hear the drone.

EDIT ~ BTW this was an Exclusive RWD with Airmatic.

StanNH

I wonder if the 4 cylinder engine is tuned differently in SA. I've never heard anything like drone with the 2.0 we get in the States.

c4004matic

Me neither. Wonder if its a windows down thing. With the windows up the engine is almost inaudible unless you are leaning significantly on the accelerator. Also in other countries acoustic glass is an option. In the US its not even mentioned so I take it its standard.

Eilers

This photo shows the laminted side window. Photo is from one of the press cars at the official Portugal launch earlier this year.

floridadriver

That would be cool, I really don't know since no mention of it on their site. I never under-estimate MB wanitng to sake some extra coins out of us with options and MBUSA doesn't always follow logic. Hopefully someone here with the car can look at their front side windows and check.

Glyn M Ruck

Yes it's possible. Our stainless exhaust material might also be slightly different. On my old Jag with it's 5 silencer system it's surprising how a stainless exhaust sounds very different to a mild steel one that is otherwise identical in design & execution. Resonances are different. More rasp from the stainless.

That said many motoring scribes from around the world & here have made a similar observation to me. We have plenty of experience with this engine from the B Class.

Another thing I noticed yesterday was how much noisier the engine sounds externally once the Airpanel grill opens. It's DI character becomes very obvious. On Alexandra's car the left side of the panel lags the RHS on opening. Things like that drive me nuts.

I should warn you that I'm extremely anally retentive when it comes to cars & audio.

Glyn M Ruck

I read them somewhere. I will try to find them. The only car I have knowingly been in with acoustic glass is the S Class.

Eilers

Oh it will not be standard..

Windshields are always laminated BTW..

floridadriver

Gotta say that Chevy, Chrylser, Buick, Ford, Hyundai,Acura, many others have it as standard on several models. If purchasing it on your own from glass supplier, you're under $75 a window difference buying laminated AG vs tempered from an auto glass shop. It does make a scientific difference, especially 2,000 Hz to 6,000 ha range.

Glyn M Ruck

Seems Edmunds agrees with me as one of many examples.

http://www.edmunds.com/mercedes-benz...road-test.html

"Is It Worth Stepping Up to the V6?
The turbo four-cylinder blends power and fuel economy in a lightweight package, making the C300 4Matic feel like a proper small sport sedan. But the smaller engine is less charming under heavy acceleration, when quick sprints to highway speed generate a raspy racket under the hood. Although the cabin is nicely insulated from road roar, the noise of a four-cylinder under hard labor still sounds out of place in a Mercedes. It's a reality we're adjusting to as nearly all small turbo engines, luxury badge or not, share this characteristic.

But these are isolated moments. For most buyers, the C300 4Matic is the right combination of performance and efficiency, with sprints from zero to 60 mph requiring just 6.5 seconds during our testing. The V6 holds the advantage of power and refinement, at the expense of slightly more dulled handling. We also found the seven-speed transmission more prone to low-speed lurching while decelerating and braking when paired with the V6."

BTW there is a software patch coming/or available that changes the tranny behaviour under braking.

EDIT: Interestingly our local motoring press finds the 7 speed more settled behind the V6 & the ride more planted. Most of our W205's sold are RWD it should be noted.

StanNH

Yes, the 4 is not nearly as smooth when pushing it hard. But it still is a quiet engine when cruising, and is not at all intrusive under normal driving conditions. I don't think anyone would claim this is a great sounding engine under full throttle runs. "Less charming" is a nice way of describing it.

c4004matic

My other ride is an S2000 which has about the same HP as the c300. With the top up and the engine running at 8K it sounds like the motor is going to explode at any moment (happily it can do it all day every day, talk about technology!) by that standard the c300 under full acceleration is a symphony! Yes the 6 sounds has a more pleasant (to my ears) tenor's fortissimo but that doesn't take anything from the 4's excellent wail in sport plus at full revs. The 8's Basso profundo when flogged is also amazing!

Jinzen

The discussion of the exhaust or engine sound is pretty moot. Both C300 and C400 sound boring to bad.

I mean these cars are not AMGs, Ferraris, or even the Jaguar F Type R - those have tuned systems designed to actually sound great. Everything else is not really part of the equation, not really a part of the buying decision.

c4004matic

In fact not true. Almost all manufacturers tune not only their exhaust sound but also their intake sound to a greater or lesser extent. The manufacturers you mention simply tune to sound like a race car but stay within legal boundaries at low speeds. That race car sound may impress the neighbors but gets annoying after 15 minutes of highway driving at normal highway speeds. Same reason I think all Harley riders with straight pipes should get run over by semis.

Glyn M Ruck

I do not drive my cars at constant moderate throttle all day on a highway. The closest highway to where I live is 20Km's away. I drive round mountains, up & down fairly steep hills & in the city mainly. The 4 pot protestations would bother me. I'll stick to refined V6's as long as I can afford the gas.

floridadriver

While on topic of road and engine noise, can anyone in the states with a C please take and post a photo of top of driver window and/or the dot stamp? Thanks in advance

MBNUT1

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MBNUT1

Given all your rebuttals regarding the 4 banger sound I am tempted to give it another try. On the one test drive I made I found it off putting for a 40K+ car and the objection was not to full throttle but moderate acceleration where it sounded like many econobox fours. Certainly did not as sound as good as my nearly 20 year old 1.8T Audi engine (though that engine without balance shafts has a lot more vibration buzz). I absolutely agree that at steady state it is much quieter and smoother than my car.

Like my friend Mr Ruck I am very sensitive to these sorts of things and refinement is one of the primary reasons for my interest in Mercedes.

StanNH

I've owned big block Corvettes, BMW inline 6's, my current Porsche 981 S and a slew of other performance cars. I like the deep sound of a larger displacement 6 or 8 cylinder car, but I also have no great aversion to the higher pitched sound of a quick revving smaller 4. Some may not like the sound of the 2.0 turbo on the C300, but I don't mind it .... and don't think it detracts from the overall feel of the car.

That is, of course, just my opinion. You may not like the sound, or the performance this engine offers.

alsyli

I don't think that Jinzen's point. MB V6's have never been that impressive, IMHO, in terms of NVH. They've always felt rather... agricultural to me.

I haven't driven the C400, but the reviews I've read about the engine (possibly brief drives in other MB models) seemed split on the quality of the engine. Some say it's very smooth, some say it's surprisingly coarse and kind for unpleasant for 6-cylinder engine.

IMO, the difference btw a decently refined 4-cylinder and a kind of coarse V6 are not that substantial, esp if the 4-cyl version costs a less and gets better mileage....

My daily driving doesn't require much strong acceleration. The 4-cyl works just fine for these relatively low stress situations....

Glyn M Ruck

Here we have to differ ~ The M112, M272, M276 are almost turbine smooth. Yes in the case of the 90 degree models they require a balance shaft to make them that smooth whereas the 60 degree does not but the balance shaft does exactly what it is supposed to. If they have ever seemed agricultural to you then something was wrong.

The M276 does make some typical DI noises but it is smooth.

The M272 DOHC & it's predecessor the M112 SOHC are utterly smooth & quiet. They idle without a shake as well.

None of them protest when driven hard either & are willing to be revved.

Jinzen

I'd rather just get a V8 C63 AMG if it was really that important to the. The V8 is going to sound incredible - the same engine but detuned from the upcoming Mercedes AMG-GT.