Richard Solomon

After relighting my trunk, I had some odd thoughts about the Bose sub - so if anyone who pulled theirs out wants to part with it, please drop me a PM.

SamLV

It isn't that bad if you play with the surround effect and spend some time.

It could be better, but it doesn't suck. I was unimpressed with the B&O especially for the price. But you are right if you mean you could install something aftermarket and get an improvement. I used to do that for myself and others until the construction of cars got far out of my league to reassemble. Too many leftover parts....

proppilot

There is no need to disconnect the battery

r1racer

I have mine tapped on the fronts...I ha a feeling something wasn't quite right. Great info as always.

subterFUSE

I never tested the rear Bose outputs, but the front door midbass does not play any signal when the system is fed a 40Hz sine wave test tone. Absolute flat line. No signal. So that means the front midbass is crossed over quite a bit higher than 40Hz. So definitely NOT suitable for tapping a subwoofer signal.
My assumption is that the rears would be crossed over the same, if not even higher.

I'm about to do a MAJOR upgrade to my system soon. One of the additions will be the MObridge DA1 preamp. That device gives an optical digital output from the MMI, and bypasses the Bose amp completely. Clean, digital, full range 2-channel stereo signal which can feed my DSP.

Cameronvs

Thank you for posting these instructions. Saved me a lot of time and headaches!

amberin10

subterFUSE,

I have been following your build information on the Audi and DIY forums. Thanks for all the valuable information you have shared.

I am planning a stereo upgrade to my 2013 A6 Premium Plus base stereo and was interested to hear how you made out with the DA1. In particular, was interested to learn if you were able to integrate the DA1 without impacting the other systems chimes/alerts/mics/Bluetooth/etc.

When I called mObridge they indicated the DA1 was not compatible with C7 but I was skeptical given your intent and the research you seem to put into these things.

Thanks for the assistance.

Allen

subterFUSE

I have not yet installed my MoBridge DA1. There is a very major upgrade planned for my system soon, but we are still awaiting the official release of a new DSP product which I have ordered. That should be coming in early November, and I hope to get the upgrade going at that time.

The information you received from MoBridge seems to be contradictory to what I have been told from a couple of sources. First, MoBridge told me via email that the C7 does work. Then, I had confirmation from an audio shop in the Bay Area which just did an install with one on a C7 S6 with Bose. They said it worked just fine.

When I was first researching the MoBridge for my car, I got a hold of some Audi Repair documents which detailed the audio system wiring and components. In those docs I learned that there were as many as 7 microphones inside the car. 4 of those mics are for the Bose AudioPilot noise compensation. The remaining 3 are located in the overhead console with the dome light. Those mics are responsible for the voice commands and bluetooth phone. One of those three mics is connected directly to the Bose amplifier. I made the assumption that if that one mic were effectively bypassed (by using a MoBridge DA1 preamp) that this would cause problems for the voice controls and/or Bluetooth phone. However, the report I got from the shop which installed a DA1 in another car was that the voice control and bluetooth still worked fine. So I went ahead and purchased a DA1 for myself and will give it a try soon.

Have I seen it working yet? No, but I am optimistic enough at this point that I purchased one and will give it a try.

The 4 Bose microphones are all connected to the Bose amplifier. They actually have their own wiring harness, which is the middle harness of 3 you will see when you open the compartment door in the trunk. The smallest harness on the left side will be the MOST fiber optics cables. The large harness on the right contains the speaker outputs.

Currently I am using the speaker outputs connected into my Audison BitOne DSP. This method has been working just fine so far. My only criticism has been with test measurements of the Bose signal. Bose has applied some very strange equalization to the factory source. Bass is rolled off very early, and there is a very sharp and big dip in response at around 200Hz. I'm assuming that they were trying to kill off some resonance issues in the cabin. All cars have them. But since I am trying to take control of the audio processing myself, the Bose EQ is no longer desired. Defeating that EQ isn't easy, however. My Audison BitOne attempted to correct it, but could only do a little bit to level out the overall response. It could not cure the big dip at 200Hz.

My solution thus far has been to avoid using the MMI as my source for music. My Audison BitOne processor has an AUX input which accepts standard RCA inputs. I got a small device called an iStreamer 12V, which is a little outboard D/A Converter designed specifically for iPod/iPhone/iPad. It bypasses the iPod's internal DAC and outputs a clean, jitter-free analog signal. I run that signal directly into my processor and listen to my music that way.

I tested the signal coming out of the iStreamer the same way I tested the Bose factory signal. The iStreamer output was a nice flat-line response, as expected. Only a small roll-off at the top of the frequency range, which I was able to EQ back flat with minimal effort using the BitOne's input EQ.

My DSP has a source control **** which we installed in the ashtray. I simply set the DSP source to AUX, and then I control the music on my iPhone. I don't have any control over the music from the MMI when I use this method, but the sound quality is better which is more important to me. If I want to listen to radio, or take a bluetooth phone call, then I just hit the source button on my DSP control and the system switches to the MMI as the source.


My hope is that when the MoBridge is installed, the Bose EQ will be bypassed because the DA1 intercepts the audio signal before it arrives at the Bose amplifier. Assuming the Bose amp handles all of the audio processing, the DA1 should give me a nice, clean signal. It outputs via optical digital.


I am also going to add a new media player from Audison. It has an internal SSD drive capable of storing and playing FLAC audio files up to 24 bit 96kHz, and outputs in optical digital. I'm going to run that directly into my new DSP for a fully digital source with no D/A conversion until the signal leaves my DSP. The media player will display its visual output on the MMI monitor so I can see which music is playing. It is controlled either by an included IR remote, or by an iPhone app. The device can also stream FLAC files from an iPhone using WiFi, which is a better solution than the MMI Bluetooth streaming.


I'll be sure to post the new build log once it gets going.

amberin10

Thank you very much for taking the time to reply, it is much appreciated.

After receiving your reply I spoke with the installer I am working with to see if a similar approach was viable given our budget. Unfortunately in my case, additional equipment beyond just the DA1 would be needed which would result in blowing through my budget.

Would just mention that I saw one of your posts on a DIY thread concerning Porsche Cayman which inspired me to add a DSP to the plan. As of this moment my plan is as follows:
- replace front dash and front door speakers with Helix Competition C63C (3 way)
- deactivate dash center speaker
- leave stock rear door speakers
- replace sub in rear deck with 2 Dynaudio Escotec MW182
- add DSP. one of the Helix DSPs, not yet sure which one
- add amp, Helix A4

Once again, thanks for the response. I look forward to hearing how things go.

Allen

DVE

What about this?

MS-8 | Car Audio DSP, Powered Digital Sound Processor | JBL US