In Line Output Convertor

[SPONGE]

Audi A6 having it professionally installed however, by site I want to ensure they are tapping into the Subwoofer speaker wire off of my bose system.

[SPONGE]

Does anyone have a picture of the subwoofer speaker wire to be tapped.

[dcc236]

You actually don't want them to tap into your Bose to std-sub wire. That is an amplified and Bose eq processed output.

It is best to pickup an unprocessed lin level out put. This can be done at the h/u or before the Bose amp. You then run that to your new amplifier and sub. Sorry, I have no pics.

[SPONGE]

I Thought the reason for the active LOC was it sums the signal again without looking for unprocessed output?

[subterFUSE]

The below post applies to the C7 Audi A6/S6 with Bose.

The subwoofer wires are located in the following locations on the T38 wire harness that plugs into the Bose amplifier:

Pin # 5 = subwoofer (-) [Brown/Blue wire]
Pin # 17 = subwoofer (+) [Brown/Gray wire]



I have an Audison BitOne in my 2013 S6 with Bose.

We tapped the following Bose outputs:

Front Tweeters (L/R)
Front Midrange (L/R)
Front midbass (L/R)
Subwoofer

7 outputs total. They are all active crossover at the Bose amp.
Keep in mind that I did a full system upgrade, not just subwoofers.

Here is my wiring diagram which I created. 2013 S6 Bose Wire Diagram - Audison BitOne Connections
Ignore the right side diagram, as that is for my amplifier and would not necessarily be relevant to you. But the left side shows all of the wire assignments and colors, and there is a picture of the T38 harness.

I tested all 7 of those outputs from the Bose with an oscilloscope and test signals. I can confirm that the Bose front midbass speakers do NOT receive any sub bass signal. I used a 40 Hz test signal and there was no signal present when testing the front midbass on my scope. None. Total flat line. I had to use the subwoofer output to get the 40 Hz signal to work.


I have not tested any of the rear speaker outputs from the Bose, however. So I cannot say with certainty whether they would supply a full range signal or not. But I suspect they do not, since the front midbass do not.

There are 4 rear speaker outputs from the Bose amplifier. 2 of those outputs go to the rear doors where there is a passive crossover, and it splits to a mid and tweeter. The rear deck speakers are called "Effects Speakers" in the Audi Repair Manual. I seriously doubt any of those rear outputs would provide a suitable signal for conversion to run a subwoofer.

Without actually testing the rear speakers, I do still feel confident that I can assume they also do not receive full range signal. My belief is that ONLY the subwoofer channel receives sub-bass signal. Therefore, if you want to add a subwoofer properly, you must tap the subwoofer output. Unless someone has tested those rear outputs and can confirm otherwise, this is the best info I can provide.

[subterFUSE]

You actually don't want them to tap into your Bose to std-sub wire. That is an amplified and Bose eq processed output.

It is best to pickup an unprocessed lin level out put. This can be done at the h/u or before the Bose amp. You then run that to your new amplifier and sub. Sorry, I have no pics.

The only way to get a pre-amplified signal in the C7 models with Bose is to purchase a MoBridge. The MoBridge will tap into the MOST optical system and provide an optical digital, stereo preamp signal. There is no "Line Out" from the head unit.

However, if you use the MoBridge then it will bypass the microphone for the bluetooth telephone and voice recognition functions. This is true because the microphone in the overhead center console plugs directly into the Bose amplifier.

The other option is to use a DSP processor or line converter to tap the amplified signal from the Bose amp and convert it to a preamp signal that you can pass to your aftermarket amps.
This option retains full functionality of the MMI features.


Based on my testing, the front midbass output from the Bose in the C7 models does not play any signal at or below 40Hz. I tested this will an oscilloscope.
Only the subwoofer output plays that low as far as I can tell.
Therefore, if you want to add a subwoofer then you will need to tap that subwoofer output. On the C7 models, the subwoofer wires are in Pin locations 5 & 17 of the T38 wire harness.

[dcc236]

What model A6 are we talking about?

[Haste]

Any way you can post that Bose Wire Diagram again? The link is not working.

Thank you!

[Christian@enfig]

What model A6 are we talking about?

Same question here.

[subterFUSE]

Any way you can post that Bose Wire Diagram again? The link is not working.

Thank you!

The best advice I can give is to purchase a 24 hour membership to Audi ErWin. Go and enter your VIN number and then download every piece of info you can find, including the wire diagrams.