Steve71

From the Burmester web site, VNC (Vehicle Noise Compensation) is described as:

"A sophisticated noise compensation (VNC) makes sure that the sound is preserved with driving noises present to guarantee the best possible musical enjoyment – on the highway or in the city traffic."

Does anyone know what VNC actually does?

MALWR

Increases the volume as the speed or road noise increases? I haven't been able to find this setting on my vehicle yet though. It was very useful on my last Mustang but not such a big deal for me with the new C300.

StanNH

No, that's the auto volume control which is under the Vehicle settings menu. The VNC is built into the system and is supposed to adjust frequency response to compensate for ambient noise. Whether or not it actually manages to do that is open to debate.

XPS

I thought this technology works by emitting the opposite frequency of ambient noise to counteract it. Effectively, it's what we know as noise cancellation.

gfmohn

You're right; it's not noise cancellation. If it were, it would be much more effective, but I have never heard of noise cancellation without headphones. Without headphones, noise cancellation optimized for the driver would mess up the sound for the passengers. At a minimum. it would destroy the soundstage.

As it is, I turn it off. My other hobby is high end audio, and I can hear the slight degradation in the sound the VNC causes. My C300 does not have wind noise problems and is otherwise very quiet. It doesn't need ambient noise compensation below 70 mph, and I rarely drive on expressways.

jolt8631

That is interesting as Sales blurb tends to point toward active noise compensation - for example, BOSE, ref their AudioPilot system: "Sound reproduction quality is unsurpassed thanks to BOSE AudioPilot® Noise Compensation Technology. This first measures the background noise within the interior. Unwanted noise is then filtered out by special algorithms. BOSE AudioPilot® Noise Compensation Technology distinguishes between desired music and unwanted interference. It compensates for interference automatically – without the need for any manual adjustment of the audio system. The advantage: the driver can concentrate better on the traffic and in-car listening becomes an unrivalled sound experience."

StanNH

As far as I know, we have no control of the VNC. The AVC has an on/off function under the Vehicle menu, and it should be left off since it does introduce distortion along with unnatural volume fluctuations. VNC, however, doesn't seem to appear anywhere other than in the literature.

nvestr

I wonder if it's noise cancellation. My Acura MDX has active noise cancellation - there are microphones in the headliner that detect ambient noise and play the opposite frequency to cancel it out through the speakers. My MDX is one of the quietest vehicles I've ever driven with regards to road noise... Not out of question that this could be what VNC means...?

StanNH

I haven't been able to find a real explanation of how Burmester's VNC actually works, or what it does. Things like saying it enhances the listening experience don't really tell us much.

In other German cars I've owned with premium sound systems, there has always been some frequency adjustment to compensate for ambient noise. This typically reduces bass and enhances the treble response. On my C300 I have yet to hear any change in sound as interior noise increases, especially over rough road surfaces, so I really have no idea what VNC is actually doing. I suspect it is supposed to be altering frequency response though.

ManiacGT

What they do need to implement is a lower volume at startup. If I've been listening to loud music when I turned the car off, when I start it next it comes back on at the same loud volume which is heart stopping from silence. Again in the BMW volume is lowered at startup to prevent this heart attack from happening.

gfmohn

I did confuse Burmester VNC with AVC (auto volume control).

I don't think BOSE has anything to do with our Burmester systems. A search of the C-Class COMAND manual shows no reference to the word "BOSE."

Jeffy

I doubt it is using ANC (active noise cancellation) or they would brag about it more. The 'compensation' they are referring to sounds like boosting certain frequency bands of the music output to better mask or be louder than ambient sounds so the music still sounds good with changing ambient conditions.

kellens

I think this is their fancy talk for equalization for the car instead of the automatic volume you can select off, this is 'built it'. I saw the same acronym for the S-class in an ad.

Steve71

I think you're right Jeffy. If it was active noise cancellation, they'd be more vocal about it.

Yesterday I sent an email to the Burmester general contact address and asked what VNC is and what it does. If (when?) I get a response, I'll post it here.

jolt8631

I get that, I was simply demonstrating my point that many manufacturers talk about active noise compensation - I used the BOSE example as it was one I recalled from my research of purchasing my wife's car.

gfmohn

[Here are the full Burmester descriptions of their systems for the Mercedes S-Class and C-Class, respectively. The URL is http://www.burmester.de/en/Company/B...-Benz-S-Class/. The first system is the Burmester system for the S-Class.]

Burmester® High–End 3D–Surround–Soundsystem

The Burmester® High-End 3D Surround–Soundsystem provides its unrivalled listening experience by virtue of 24 high-performance speakers and 24 separate amplifier channels with a total output of 1.540 watts. At the same time an intelligent combination of analogue and digital amplifier technologies leads to a particularly fine and natural sound together with high performance reserves. While sophisticated analogue filter settings allow the best possible fine reproduction in the mid-range and treble frequencies, the digital amplifier - despite its compact dimensions – masters the highest dynamic peaks. The result is outstanding sound resolution and fine acoustic detail, combined with impressive impulse reproduction. This provides a rounded, warm and substantial sound experience founded on an impressive bass range.

The new, three-dimensional listening experience provided by the 3D-Sound and created by the Burmester speakers integrated into the vehicle roof is unique. In addition to the two speakers in the overhead console, another speaker is accommodated in the overhead control panel. A 3D–Sound algorithm was developed specifically for the Mercedes–Benz S–Class to create the unique listening experience made possible by these overhead speakers. The aim of the developers was to add a subtle spatial effect to the outstanding listening experience.

Apart from 3D–Sound, four other preset sound modes can be selected to suit every taste and audio source:

Pure – audiophile sound reproduction with no additional effects, for unadulterated musical enjoyment
Easy Listening – milder sound background for relaxed listening over longer periods
Live – appealing, dynamic sound background akin to live music
Surround – virtual surround sound

Using the so-called VIP setting, the sound quality can be optimised for any of the four seating positions. This function has been carefully configured for each of the sound modes shown above. The sophisticated sound compensation (VNC) has also been developed further. This ensures that the best possible sound impression is maintained despite changes in driving noise. VNC guarantees maximum listening pleasure at all times – whether on the motorway or in town.

As a visual highlight, the tweeters in the mirror triangles of the front doors are particularly sophisticated. When the head unit is switched on, they rotate by 360° and perform a screwing motion of ten millimetres towards the occupant. This ideally aligns the tweeters for an optimal sound impression.

If the ambience lighting is switched on, the two tweeters are illuminated in one of the seven available colours. The same applies to the overhead console, which is also elegantly emphasized by the ambience lighting and accommodates two of the three overhead speakers.

[This is what we C-Class pilots are missing out on. The accompanying photos show that this high-end system is identified by the logo "Burmester High End" engraved on the tweeters in the mirror triangles by the front edges of the front doors.]

[The following is the Burmester system we C-Class drivers get. This system is identified by the logo "Burmester" only (without "High End") engraved on the tweeters.]

Burmester® Surround–Soundsystem

13 high-performance speakers, a 9-channel DSP amplifier with a total output of 590 watts and amplifier/speaker systems configured specifically for the vehicle make for the first-class Burmester® “Wohlfühlklang”. If required the impressive listening experience can even be heightened. The Surround function generates virtual surround sound from a mono or stereo music signal to maximise the spatial effect. Front/Rear optimisation allows the sound to be specifically adjusted for the front or rear seats.

Thanks to highly advanced vehicle noise compensation (VNC), the sound quality is maintained despite driving noises so that the best possible musical enjoyment is guaranteed at all times – whether on the motorway or in town. The Burmester® Surround–Soundsystem combines digital and analogue filter elements. The systematic use of analogue diplexers in the medium and treble ranges ensures an extraordinarily expressive and natural spatial sound.

Additional features of both systems

Dieter Burmester personally attends to the fine-tuning of the system to suit the vehicle and its interior acoustics. As the founder of the company named after him, he not only has recourse to the very latest measuring systems, but relies on what the sound system was designed to please – the ear.

The innovative Frontbass system developed by Mercedes-Benz and used for the first time in a saloon car is a feature common to all the audio systems: the woofers are housed in the firewall, and use the almost 40-litre space in the cross-member and side member as a resonance chamber. Conventional woofers in the doors are therefore unnecessary. The midrange speakers in the doors are relocated upwards. This improves sound brilliance and allows additional stowage space in the doors.

[Notice the differences in the number of speakers and the rated power. Nevertheless, I am definitely NOT disappointed in my C-Class sound system!]

Steve71

I received the following response this morning:

"Thank you for your request which we would like to answer as following.

The interfere influences on your sound, so the driving noises, will be technically measured. By algorithms these influences will be compensated so that the sound can be preserved.

Please be informed that the function is a noise compensation not a noise cancellation."

My interpretation of this is that the system somehow measures "drive noises" and applies an algorithm to compensate. As he says it doesn't "cancel" noise, I suspect it increases sound levels for some set of frequencies based on what it measures.

Mike__S

Bose is simply a volume control trick. Ambient noise increases with speed, radio volume is increased. Many car radios now have similar, manual speed relative volume control (VW in particular comes to mind)

Burmester is implying that their multi-channel amp setup is also, somehow, frequency dependent, which may or may not be true. It sounds a bit mouse, if you ask me. True, fully balanced anti-noise signals are not possible over the entire sound field of a car interior, but I could see frequency biased spacial enhancement through the various speaker placements.

I just do not have the impression the Fender's, Burmester's, and Bose's of the car audio world are that clever. I say this because the C-Class Burmester speakers are just off the shelf junk with their brand name on it. And it sounds like it, too.

My suspicion on the even the high end luxury cars is that we get charged 5k for 2k of components and 25k of engineering time to make it fit the space available and not sound crappy. The rest, some 2 or 3k per car just goes straight into someone's pocket.

Car interiors are a very tricky box to get good imaging and sound balance. That alone is a huge challenge. Plus there is road noise. Even with 17" wheels and the acoustic comfort package there is still "white" noise from the tires on all but smooth asphalt surfaced. This alone pretty much kills any serious listening when compared to a quite living room experience. Just keep that in mind.

What I hope everyone is getting with the E-Class and S-Class, 3-d Burmester setup are ultra low distortion speaker components. Most car audio is total junk and the biggest problem is simple high distortion of mid-range and tweeters. I'm talking multi-percentage point distortion here. If Burmester simply delivers a midrange and tweeter package of less than 1% harmonic distortion, this is worth the money. Adding a DSP unit and multi-channel amp pathways is just frosting on the cake.

I tested an E300 with the 3-D Burmester this weekend and it is sonically quite good. Obviously a very clean low distortion sound. It has sharp attack and plays high dynamic range recordings faithfully without any signs of stress. It is far beyond the C-Class kit. So, it is a good system. Whether it is ~$5000 good is a separate question.

Mike5215

I think the vehicle noise compensation is a little more complex than speed dependent volume, and a lot less complex than noise cancellation. We tried to pin down the VNC circuit during the Focal/Audison upgrade. (It was kicking up a bunch of random low frequency bursts after the Audison DSP was installed). There were no cabin mics we could find after ruling out the most obvious locations. A support call to Burmester corporate was answered by someone who wasn't aware they made, much less supported, car audio products. Mercedes didn't know if there were mics, much less where they were.

In the end we defeated it by passing the signal thru a JL Fix82 integration unit before the Prima. No idea why that did the trick but it worked.

Mike__S

Mike5215,

Interesting. Now you have me wondering. I have realized that my 1970's education is not keeping up with technical developments very well these days, and I ought reduce my skepticism about some manufacturer's expensive, high-end audio systems.

The problem today is no one is taking the time to explain these things to the public, figuring they would not understand, or do not wish to take the time to do so. The alternative are highly technical academic PDF's explaining theories from which you become expert enough to explain it to yourself. And that takes even more time.

This is mainly because application specific, commercial organization research papers have become monetized on the web, making casual access problematic. A secondary source are published patents, however, so many today are speculative tracts filed by lawyers themselves making separation of the wheat from the chaff difficult for other lawyers, much less laymen.

Anyone seriously interested in noise cancellation or anti-noise may start with this somewhat odd article on acoustic gaming. It happens to both discusses the pertinent human hearing background, and discusses basic sound orientation techniques: http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf It gives required basic concepts through chapter 2.5

Based on that reading, your description of low frequency bursts would be just what is expected of anti-noise compensation, albeit in modified form. If limited to just the low frequency range, human hearing will not differentiate its orientation very well, if at all, so my skepticism regarding a full anti-noise algorithm nor another's question about using only headphones do not apply.

Directional sound orientation is frequency dependent and does not depend on angle of incidence. We do not orient low frequency sound at all, and starting at roughly 100 hz on downward even partial orientation rapidly requires a louder and louder signal exponentially.

This fact is an ideal happenstance for attacking all the low frequency thumps and bumps of road induced noise, but does not help too much for the wider and higher frequency "white" noise generated by tires on some running surfaces, particularly pitted concrete or rough asphalt.

However, from a brief web survey, it now appears that multi-speaker systems and sophisticated DSP can cope with such noise sources to the extent of 10db to 20db attenuation. This statement is based on claims in recent technical paper and patent abstracts. Recall that sound pressure (db) measurements are logarithmic, so 10-20db is huge if it gets cabin noise down into the 50 db maximum range or lower.

If I get more time, I will research the Mercedes/Burmester side of this some more. We have to consider that Mercedes and/or Burmester public information specialists are probably just as much in the dark as we are. Besides, they are also under orders. Corporations have been playing cat and mouse with the press and public for some decades already, telling you what they want you to hear and nothing more.

Mike5215

I think, and I'm just guessing, that VNC boosts audio system frequencies that are competing with ambient cabin noise...wind, tire, exhaust...to boost them to the extent they mask the noise. That would seem to require the system to be able to "listen" to ambient sound in the cabin, compare it to what it's putting out as audio, then analyze and compensate in real time. It seems very ambitious and costly in a system that frankly isn't great. I have no idea how it works, or even IF it works in any audible way. My system obviously no longer has VNC and I couldn't tell you the difference in ambient noise vs stock with the VNC active. Seems exactly the same to me.

Mike__S

The C300 probably does not have such a comprehensive system as I am describing. It would only be S-Klasse and E-Klasse Burmester 3d for which medium four figures are charged, OK?

This is little black box stuff, but sound augmentation theory has been around for at least three decades now. First automotive tests were in 1990's with a station wagon, because the equipment took up so much space! Those days have passed, and there is no reason single chip, dedicated, tuned digital signal analyzers are not available for automotive radio systems.

The best way to track this down is for someone to do a search of the W213 and/or S-Klasse parts catalogs for "microphone". The "Telephonics" voice microphone will be of limited bandwidth so other noises will not be picked up other the spoken word. Such a system will need a couple of full range microphones to feed information to the processor.

So, I'd suggest next step would be a microphone search in the parts catalogs. IF we find a part number different than the command system microphone and maybe a location illustration, we have hit pay dirt on the Burmester 3d system.

Mike5215

I have access to MB's entire online parts catalog (STAR EPC...you can too for the low, low price if $75 a year) and I can't find a cabin mic other than the one in the mirror housing for voice command and BT on my 300.

With respect to the difference between the $6400 3D Burmester in the 222/215 vs the standard Burmester, if MB holds true to form the systems share the same basic drivers, just more of them and with more amplification, plus a healthy helping of utterly pointless eye candy, i.e. Motorized and illuminated tweeters. The quality of the components doesn't change, just the quantity. My guess is the same VNC is carried thru the S, E and C. Might be tuned differently but the same basic gear.

Mike__S

Hum... That is not my experience with commercial, high-end home speaker makers such as B&W or Audiovector (there are others). Audiovector will sell you the same great Danish cabinetry with or without cabinet reinforcing, three different tweeters and two different mid-range diver sets. The highest level is a bit over the top price wise for a small gain, but between the other three, there are audible differences. As I said, and expect, the Burmester 3D ought to show different part numbers. If you have access, please check when you have a spare moment. Many of us would like to know.

Based on what I have heard in the 3D equipped E300 and the optional Burmester equipped C300, the speakers of the E300 had much less distortion and better transient response or better definition of transients. Mind you, this is for the 3D option, not the Package 1 Burmester, which probably does just have more speakers from an "off-the-shelf" source. After all, we are dealing in 100,000's of units, possibly the same ones as fitted to the C300. This scenario would meet both your and my expectations.

This higher opinion of the 3D option was established back to back with a couple recordings I am familiar with. For example there is a full orchestral 'splat' that includes timpani and base drum at the end of a Greig Peer Gynt Suite recording that sounds like everyone all hit together, on the beat. Then, you listen on speakers with tight base damping and excellent transient response for all speaker elements and you realize the timpani was a split second early. Undoubtedly not a standard of comparison for casual music listeners, but this is what sets great speakers apart from good ones that otherwise sound nice and musical. That kind of detail is no accident. It takes well made components of tight quality control and careful design.

Car audio amps are notorious, even today, for their poor electronics, high distortion, low RMS power and poor transient response. Then, most speakers are equally poor in quality. I made the point that just cleaning this mess up goes a long, long ways towards excellent sound. It is when we start having acronyms and non-standard terminology thrown about that my skepticism builds. This situation is a case in point.

That the Burmester 3D tweeters extend from the housing is another interesting point. Many excellent sounding, high end home audio speakers these days (again B&W and Audiovector, with which I am familiar) have an ambient air port behind the tweeter unit, or in some cases they are even free standing. It is difficult to get full dispersion from tweeter designs, and the rear port allows a wider listening field and a more open sound on the high end. This is partially listening space character and speaker placement dependent.

Here, with the tweeter in a corner, so to speak, it is an ideal case for lifting it out of the corner slightly so the high treble sounds are not so highly directional, but such that sound is also radiated off the glass of the windscreen and side windows. It is a lot of trouble to go to, but I do not believe it is pointless eye candy. Just expensive eye candy. Such details are why sound systems sound different from each other and some better than others.

I still have no technical details for what Burmester is calling VNC. As was pointed out, if it was technically brilliant, we should expect it to be explained as such, if in laymen's terms. Instead, we have relative silence and mumbo-jumbo from Burmester so far. Just the simple question of it being an active (digital signals processing) or passive (no digital signals processing enhancement) still a moot point, carefully disguised by vague terms of noise cancellation vs. compensation. The big question is if it is active or passive, and if active, how so and to what measurable extent in db between original noise and compensated noise components over what frequency ranges.

I for one have become quite curious about the possible design and mechanical differences, as $4,500 to $6,000 dollars is involved. One may not get rich worrying over 4 figure amounts, but one will stay wealthy into old age doing so.

Mike5215

I can check. I need a VIN for a car with and one without the 3D upgrade. If you can hunt me down those I'll run them through EPC.

The workhorse driver in all the new MB sedans, 3D or not, is a 4" woofer. They're in all four doors, and used as center dash and rear surrounds. I'll wager they're all the exact same unit, C/E/S, 3D or not. They'll have unique part numbers to the chassis they're assigned to, but within a chassis they'll likely be the same, base vs 3D. I may be wrong, would be interesting to find out.

With respect to the snazzy tweeters, the rotating baffle in the upgraded illuminated Burmester was preceded by the equally silly, also illuminated "Acoustic Lense" tweeters in the W221 Bang & Olfsen upgrade. To look at them, at first glance they're very exotic and expensive. But pull one apart and you have a cheap off the shelf 1" silk dome tweeter mounted horizontally and fired up into a cone shaped diffuser. Which of course wouldn't be necessary had the tweeter been mounted vertically, but would you spend $6400 with nothing outwardly visual to show for it? Mercedes bet "no".

When a car company sells you a "premium" audio system, there's always a healthy dose of marketing puffery and cosmetic sleight of hand along with the increased fidelity. It's not a total rip off, but the mark-up is such that for half the money you could build an aftermarket system that sounded twice as good.