subterFUSE

As has been mentioned more than a few times already, I am something of a car audio nut. We removed the aftermarket system from my previous car before trading it. The majority of that gear will eventually end up in my new S6.

This thread will be my log for everything from the initial research and planning, to the installation and final results.

subterFUSE

The first challenge with integrating audio into the Audi is that we can't easily replace the source unit without losing a lot of functions for the car. The MMI must remain intact and act as the source. Gone are the days when every car had the standard DIN or Double DIN sized openings in the dashboard. It was so easy to buy the head unit you wanted and install it. Now we have radios and navigation integrated into the dash along with climate control, etc...

The solution to this has been to use a line output converter, or signal processor. Instead of using traditional Pre-Amp inputs, these converters can accept an amplified signal and convert that to a pre-amp signal. This allows you to connect aftermarket equipment to the factory amplifier without affecting any of the car's audio system upstream from that point.

In my previous car, we used an Audison BitOne to integrate into the BMW's Logic7 stereo. The BitOne will serve as the brains of my new installation in the Audi.


In addition to the BitOne, there is another piece of equipment which I am researching that will aid in the integration with the Audi MMI/Bose. That device is called the MoBridge M1000-M-DA1.

Click Here for Link to MoBridge site

The MoBridge is a digital pre-amplifier that can connect directly to the MOST fiber-optic network. It then outputs a Stereo pre-amp output via Optical Digital connection. This means there would be no Digital-to-Analog or Analog-Digital conversions, and we will get a digital signal which we can then direct into our aftermarket equipment.

The Audison BitOne has an Optical Digital input. So the MoBridge would connect to the MOST fiber network and output an Optical Digital signal. We connect the digital output to the digital input on the BitOne. The BitOne then processes that signal in the digital realm, and outputs a digital signal to my Audison amplifiers. The Audison amps connect to the BitOne via Ethernet cable. The signal remains digital all the way to the amp, where it is finally converted to analog by high quality, 24-bit Wolfson DACs and then played on the speakers.

I have been in contact with techs at MoBridge for a few weeks already. They have tested their preamp on the latest generation Audi cars, and it works. The only issue they had was with models that have the Engine Auto Stop/Start feature that shuts the engine off while pressing the brake pedal at a stop. The Start/Stop feature was causing their equipment to shut off. They were working on a firmware update to remedy the situation.
But, more importantly for me.... I don't believe the S6 has the Start/Stop feature. So I don't need to be concerned with this minor issue.

A more important issue potentially arises from the Noise Cancellation feature on the S6. Apparently there are microphones installed in the car which detect noise when the engine runs on 4 of 8 cylinders. The mics playback this noise out-of-phase from the Bose speakers to cancel the perceived sound for the occupants. Kind of like a giant set of Bose noise cancelling headphones. While this is a neat feature for a car, it would create problems if trying to integrate a high-end audio system.
I want the BitOne to do the audio processing, not a noise cancelling system from the car.

The folks at MoBridge claimed that the microphones were connected directly to the Bose amplifier. This is a topic which I must research to confirm, but if they are correct then that is excellent news. Since the MoBridge plugs into the MOST network, it grabs the audio signal upstream from the Bose amplifier. Anything that happens to the audio signal from the amp down would be nullified. That would include the noise cancellation, assuming they are correct about the microphones connecting to the Bose amp directly.

DeerHunter

Let us know what 4-cylinder mode sounds like once the noise cancellation feature is disabled. Looking forward to your updates to this thread.

subterFUSE

Visited Ultimate Auto yesterday to discuss plans for the audio system in the S6.

The primary topic covered was speakers for the front stage. In the BMW, I had a set of Hertz Mille 2-way component speakers. (6.5" woofer + tweeter) These were very expensive speakers when I bought them in 2009, about $2500 for the set. (2 woofers + 2 tweeters + 2 passive crossovers) I ran these speakers with active crossover from the BitOne processor.

In the Audi I want to go with a 3-way speaker active-crossover setup in the front. The Bose system already has 3-way speakers which will make the installation very easy. I should not need to cut any of the door panels and I can also keep the factory grills for a completely stealth installation.

The first question was whether to keep the existing Mille speakers and simply add the midrange speaker, or to purchase a whole new set of speakers. This was a question for the guys at Audison/Hertz so we gave them a call. My concern was that my Mille speakers are a few years old and they have made some minor design changes since then. I wanted to be sure that if I purchased a midrange speaker it would work well with the older woofer and tweeter. Luckily, they said this would work quite well, especially with an active crossover. In fact, one of the guys at Audison had added a newer midrange to his own car.

The Mille ML700 midrange speakers are currently on backorder until sometime in September. But I will plan on ordering a pair of these and keep the Mille 6.5" and tweeters. So the topic of front stage speakers is now settled.

I will need to purchase an additional amplifier to power the three-way speakers. I already have an Audison Voce AV5.1k amp which is 5-channels. That amp will run the 2 tweeters, 2 midrange speakers, and the subwoofers. 75 Watts of Class A power to the tweeters, 140 Watts of Class AB power to the midrange, and 1000 Watts of Class D power to the subwoofers. In order to power the 6.5" woofers up front, I need to buy an Audison Voce AVdue amp. This is a 2-channel amp delivering 260 Watts per channel.

I have decided not to install any rear speakers other than the subwoofers in the trunk. Still not 100% decided on the subs, but most likely will be running 2 JL Audio 10W6v3 woofers in a sealed enclosure. Or perhaps I might do 2 JL Audio 8W7 woofers?

Total system power will be 1950 Watts.



Signal chain will be as follows:

Audi MMI
MoBridge DA1
Audison BitOne
Audison Voce AV5.1k
Audison Voce AV Due
Hertz Mille System MLK3 (tweeter, midrange, woofer)
JL Audio subs (10W6v3) or (8W7)?

Delurker

Definitely keep us posted on this - I've been waiting for MoBridge to certify their unit for the new S6, as I've got a pair of Arc Audio amps and Focal 3-ways & 13" sub that I'd like to replace the crap Bose system in my S6 with. Not as fancy as your stuff, but I'm sure it'll be worlds better than what I'm putting up with now.

Same as you, I don't intend to put anything in the back besides the sub, I prefer the imaging with music coming from in front of me.

subterFUSE

I've been in contact with MoBridge already, and they said that it works with the latest generation MMI. The only issue they had was in cars with the Engine Auto Start/Stop feature. But I don't think the S6 has that, only the smaller engines.

The issue I am still trying to get confirmation on is the active noise cancellation. We need to know exactly how that is connected to the Bose system, and possibly will need to defeat it.

Another topic I need to get answered is how the tones for the parking assist work. In my BMW before this car, the parking sensor tones would beep via the stereo system speakers. That creates a minor issue for the MoBridge because the DA1 preamp only outputs a stereo signal. So the directional sounds from the parking sensors would be lost, with the tones playing from all speakers simultaneously.

The tech at MoBridge with whom I've been messaging told me that Audi uses separate tone generators for the parking assist that are independent of the Bose stereo system. I remain somewhat skeptical of this, however. I must confirm it on my own.

Delurker

Good stuff! I think I can live with the parking sensors not being directional, but I'm going to hope the MoBridge tech wasn't blowing smoke because it is nice to know which sensor is going off without looking at the display.

I think the Euro spec S6's have stop/start, but it's not on the ones they ship to the US.

I had heard that the mics in the car connect directly to the Bose amp; it may have some kind of internal processing for noise cancellation, which I wouldn't expect to be an issue if the amp is removed.

subterFUSE

To be accurate, the Bose amp is not actually removed. You can leave it in place. It will just be disconnected from the speakers.


I'm looking at a repair manual now and it does confirm that the Noise Cancelling Mics are connected to the Bose Amp. So there should not be any need to defeat that system if using the MoBridge preamp since it should intercept the signal upstream from the Bose amp.

I'm going to make a phone call to the MoBridge offices in California later today to see if I can speak with a tech about it.

subterFUSE

Just spoke with the guys in California who distribute MoBridge, Audison and many other brands. They said the DA1 works in the latest Audi MMI, except for the Bluetooth. A third-party Bluetooth system is required that can plug into the MoBridge.

Edit: Upon review of the Bose system wiring diagram I have here, I can see why the MoBridge would cause the Bluetooth to not work. The microphone for the telephone plugs into the Bose amplifier. The MoBridge would effectively bypass the Bose amp, so anything that is connected to the Bose would also be lost.

Unfortunately, that is a limitation which will force me to abandon the MoBridge idea. I don't want to lose Bluetooth, or use a third party option. The integration with MMI is really nice and I want to keep that.

Therefore, my plan will now be revised to simply using the Audison BitOne connected directly to the Bose amp via high level inputs.
We will have to disconnect the Bose AudioPilot microphones that are located in the headliner. There are 4 mics total. They look like little buttons in the headliner, two in the middle of the car and two in the rear.

DeerHunter

Why are you set on eliminating noise cancellation? If you can retain it, so much the better, I would think.