Make your own free website on


Back to a6retrofit website index

Will the real MMI please stand up? Difference between standard radio Concert/Symphony and the optional DVD navigation's MMI controls in B8 platform Audi A4 and A5 (by LoCal)

25.6.2008 (updated 22.7.2009) - A fellow Audi enthusiast LoCal sent in this contribution and I thought it would be worthwhile to publish here, maybe it can be of use for anyone thinking of some retrofits on the new B8 platform. Thank you, LoCal!

UPDATE 8.4.2009: The article below compares Audi MMI 2G with the Concert/Symphony radios in current A4 B8/A5 cars. In general, it also applies to the Q5. However, Audi is since late 2008 shipping the cars with third generation Audi MMI 3G when the navigation option is selected. MMI 3G is a new version of MMI 2G. For most of this article, you can think of MMI 3G same as MMI 2G.

As MMI 3G is much like MMI 2G in principle, the difference between MMI 3G and Concert/Symphony radios is the same sort as the difference between MMI 2G and the radios was. Most of this article still applies to MMI 3G too. Beware of some differences, though, for example MMI 3G does include memory card slots just like the radios do (which the MMI 2G did not include) - other differences in details are likely to exist as well, but the overall principle remains the same.

MMI, be it 2G or 3G, is a different system than the Concert/Symphony (or Chorus) radios in Audi A4/A5/Q5.

UPDATE 22.7.2009 - For an updated take on the radios and MMI, see also:

Summary of current Audi multimedia systems and history

See also this interesting guide to Audi multimedia systems (pre-MMI 3G):

Audi In Car Entertainment Systems

The New MMI Generation from Audi - Top-Level Multimedia and Communication (links added 25.5.2009)

UPDATE 20.6.2009:

Audi MMI 3G videos:

Audi | MMI Navigation plus Basic Information

Speculation and discussion about next-generations of MMI after 3G:

Audi MMI 4G in the next A8?

25.6.2008: When Audi introduced the latest-generation Audi A4 B8 (8K) in 2007 and the Audi A5 (8T), also based on the B8 platform, a year earlier, it made the MMI control logic standard on these mid-range models. All Audi A4 B8s and A5s (simply referred to as A4/A5 from this point on in this article) feature a screen (colour or monochrome) similar to bigger models A6/A8/Q7 and familiar MMI controls.

Less understood fact is, however, that unlike A6/A8/Q7, where it is a standard feature (although with a few different equipment levels), Audi actually did NOT make the actual, "real" MMI standard on the A4/A5. There are actually two entirely different technologies available for the A4/A5 media experience: on one hand the Concert/Symphony (and Chorus on some markets) radios which do not feature actual MMI (just a look-a-like, a pseudo-MMI if you will), and on the other, the navigation system(s) which do feature the actual MMI. This article is here to explain what the difference is and what this means for the car buyer/owner.

A bit of history first: Audi introduced its BMW iDrive like (although far superior) MMI, short for Multi-Media Interface, in the current generation Audi A8 back in 2003. For the user it featured a new user-interface complete with a full-colour screen and a rotating knob as well as a number of other control buttons in the center console below the gear lever that controlled the radio, CD, phone, navigation and car settings.

Beneath the surface, MMI in A8 introduced the standard MOST (Media Oriented Systems Transport) bus to an Audi, a superior data transport compared to the older CAN bus (which is still used for other functions in the car even with MOST). The MOST bus is a fiber-optic cabling loop going from one component to another inside the car. The whole MMI setup is decentralized - instead of an old-style everything in one radio/navigation box in the center console, MOST allows separation of components because it can transfer data, including fully digital audio data, digitally and faster than the older technologies would allow.

On an MMI system one can find components all over the car, e.g. a front control box behind the glove-compartment, CD changer and Audi Music Interface in the glove compartment, phone module below the drivers seat and a host of components in a small rack on the left side of the trunk (navigation, TV, radio, amplifier, speech dialogue system). All of these components move data using a fiber-optic cable that goes from one component to another in a chain/loop. (Well, all expect TV and the rear-view camera, which use a composite video cable to transfer video data to the front controller box because, I speculate, MOST bandwidth isn't capable of transmitting video data.)

The chain/loop nature of MOST is also, why, if one component in the MOST chain fails, the entire MMI goes blank. The car still works, but the media systems - radio, phone, etc. - are all out of operation.

Next Audi used this technology as standard in the A6 and Q7 introduced a few years later, this time, in some markets, offering two variants on the MMI: monochrome-screen MMI basic (and basic plus which featured a better radio/amplifier) and the 7" colour-screen MMI High. Both had the same controls beneath the gear level like A8 (although later some buttons were removed from MMI basic cars in some option configurations) and both used the same fiber-optic MOST data transport underneath. Some components like MMI basic plus amplifier and CD changer were shared by the MMI variants, others were different like the front control box (on an A6 MMI basic actually includes the single CD drive and the front controller in the same housing, unlike on MMI High where the front control box is separate from the CD drive) and the navigation box (CD navigation for MMI basic and DVD for MMI High).

So, that is the story behind the actual or "real" MMI - which also seems to be a retro-fitters dream since the decentralized components allow adding new options later.

Bear with me for a while more: As a sidetrack Audi also brought their MMI operating concept to the Audi A3, TT and last-generation Audi A4 B7 a few years ago in the form of revised navigation devices. Both monochrome screen (MMI basic-like) and 6.5" full-colour screen (MMI High-like) navigation devices are available for these cars with CD and DVD navigation respectively.

These navigation devices look a lot like the actual MMI, they actually also say Audi Multi-Media Interface upon starting, but technically they have very little to do with the actual MMI explained earlier in this article. For example, buying an "Audi MMI" DVD navigation disc won't work in one of these units, even if your car does say MMI on the navigation screen - you'll need a disc marked with e.g. "RNS-E" which refers to the navigation unit. Basically these are old-style CAN bus based all-in-one-box, souped up, pseudo-MMI radios that have the MMI controls placed on their front panels (instead of below the gear lever). In this regard they are "lesser" technology compared to the actual MMI, but ironically the navigation mode in the A3/TT/A4 B7 DVD navigation is actually far superior to the one in the actual MMI on A6/A8/Q7... (Rude surprise to many A4 B8 buyers because A4 B8 gets the MMI A6/A8/Q7 navigation, not the better pseudo-MMI A4 B7 navigation.)

Now, finally on to the A4/A5 and the true story about the MMI in these cars!

A4/A5 comes standard, depending on market, with one of the radios: Chorus (single CD, no SD, monochrome screen), Concert (single CD, SD, 6.5" colour screen) or Symphony (integrated CD changer, SD, 6.5" colour screen). The MMI controls are placed on the front panel of the radio/CD like on A3/TT/A4 B7, although the screen is separate like on A6/A8/Q7.

The place of the MMI controls may be the most visible and notable difference, and something that has come as a nasty surprise to many A4/A5 buyers that have previously only seen pictures of A4/A5 with MMI controls below the gear lever (where they are in cars with navigation/actual MMI). Some dislike it, some prefer it, but this is a very important thing to understand: if you do not order a factory navigation system for your A4/A5, the MMI controls will be on the front of the radio/CD unit instead of below the gear lever in the center console.

Like the reader probably has guessed by now, these standard radios have more in common with the all-in-one navigation devices of A3/TT/A4 B7 than with the actual MMI in A6/A8/Q7. They may look like MMI, but they are just souped-up radios. There is no MOST data transport in the car, thus lesser decentralization of components (and expansion possibilities) and the colour screens are 6.5" instead of 7" like on the actual MMI. The user-interface is also slower compared to the actual MMI. Unlike on the A3/TT/A4 B7 navigation units, Audi doesn't even claim this system is MMI, upon starting it actually says Audi Information System on the screen (although controls and graphics are very, very similar to the actual MMI).

The actual MMI, same as in A6/Q7, is available for A4/A5 in the form of CD and DVD navigation options. Selecting CD navigation from factory includes the equivalent of MMI basic with monochrome (red on black) screen, DVD navigation the equivalent of MMI High with 7" colour screen. (CD navigation not available in all markets.) Both versions include the MOST data transport, decentralization of components, separate CD changer, MMI control buttons beneath the gear lever in the center console - this is pretty much the same system that comes standard on the A6/Q7. It looks a lot like the standard A4/A5 radios do, but technically is a completely different beast.

So, other than the already mentioned location of the MMI controls, usability performance and a half an inch difference in colour-screen size (and addition of navigation obviously), what differences are there for the car buyer between selecting a one of the radios or the navigation?

For many, not a lot.

Both systems feature extensive car settings (although they differ a bit in a few details), both have pretty graphics and the same great MMI control logic. Both allow Audi Parking System Plus to display parking sensor data on the screen. The general audience won't care if there is a MOST fiber-optic loop or an old-style CAN bus doing the talking for them, they all pretty much work the same.

There are some subtle differences, though (in addition the not so subtle location of the MMI control buttons difference) that might be significant to more demanding buyers.

First, something the radios have and the MMI/navigation do not: an SD card slot for loading MP3 music. This is a feature of Concert/Symphony radios (not on Chorus though) and not present on MMI/navigations systems (although can be solved by getting Audi Music Interface and a separate USB card reader for the car).

Second, digital audio transport on MMI/navigation cars. At first this may not sound significant, but buyers selecting the B&O audio option have reported differences between cars that have one of the radios compared to cars with the MMI/navigation. B&O comes with a different amplifier depending on whether or not the car has the MOST data transport. On cars without MMI/navigation, audio from the radio in the front is transmitted analogically (radio is in line-out mode) to the B&O amplifier in the trunk, on cars with MMI/navigation this transportation is done digitally using the MOST bus. Thus MMI/navigation cars are able to offer some additional user-options for the B&O amplifier like some extra surround processing that are not present on cars without MMI/navigation. Some users have also reported inferior sound quality on cars without MMI/navigation, which might be explained by the analogue line-out audio transport instead of going all digital over MOST.

Third, expansion. Many options for A4/A5 depend on the presence of the actual MMI. These include the SIM Access Profile phone module (although a lesser phone-prep is available for the radios as well), full speech dialogue system, television as well as Audi Parking System Advanced with its rear-view camera. Obviously this concerns both factory orders and retro-fitting options. For example, the Dension 500 requires MOST, so available currently only for MMI/navigation cars. Choosing MMI/navigation greatly expands your options in this regard. Audi Music Interface (AMI) used to require MMI/navigation also, due to being based on MOST, but model-year 2009 introduced a non-MOST (CAN) version of AMI that is also available for use with the radios. (Audi information system ETKA shows two different versions of AMI, one for the CAN radios and one for the MOST MMI/navigation.)

Fourth, Drive Select. If you spec Drive Select for your A4/A5, the presence of MMI/navigation will move the Drive Select control buttons (and ESP, sunscreen and parking system buttons) from below the gear level to below the CD changer in the dash. Also, Drive Select drivers with MMI/navigation get an extra option, Individual, that allows them to more directly define Drive Select characteristics. Without MMI/navigation, the Individual mode is not available.

Remember to order navigation for your A4/A5 if you want the "real" MMI. Also, look forward to a third-gen version of said MMI in the Q5 later this year (with much improved navigation, DVD video playback and improved card media connections) and perhaps introduction in the A4/A5 model ranges in the future as well...

Oh - one more thing, nothing to do with MMI but a source of some confusion as well - if you want the aggressive LED daytime running lights (DRLs), make sure your car configuration includes the Xenon driving lights. Only with the Xenons does the A5 come with its signature LED light strips in the front, without Xenons you'll only get a few small conventional bulbs as DRLs.


UPDATE 12.3.2009: Interesting discussion about MMI generations below.

MMI 2G, 3G... but what was 1G?


By LoCal

Back to a6retrofit website index

DISCLAIMER, TERMS OF USE: Please feel free to share, copy, mirror, link to and use any information on this site freely, it is there to hopefully help you and others. However, understand that I am no professional, not affiliated with Audi or anyone and anything posted here may and probably does contain errors and omissions, so take it with a pinch of salt and use it at your own risk. I recommend always consulting a professional, your dealer or Audi when in doubt. The content on this site is provided as is, with no guarantee of usefulness, correctness or fitness for any purpose. Any advertisements that may show up on this site are displayed by the hoster of this nice, free web space, I do not benefit from them.

This site used to be available at: