Papabaehr

I have a 2013 A6 Prestige with Bose system. Ive always done aftermarket audio work on my prior vehicles without an issue, but that was working with aftermarket headunits with preamp RCA's. That being said this car has MMI and the strange Bose Stereo. I noticed the back panel vibrates on bass hits from the weak factory sub. Ive ordered Dynamat extreme and enough extra to take care of other spots besides the rear metal panel the factory sub sits in. That seems to be the main spot of vibration...anyways Im going with an aftermarket Amp and subs and a line converter. Heres what Im going with-
JL XD600/1 amp
JL HO110 W6v3 Ported HO WedgeTM Enclosure
Audiocontrol LC21 2 Channel Line Out converter and sub control
obviously nice 4 awg wiring kit high end Rca's

Ive read things on here about getting different issues in sound quality based on which wires you tap into. Im not sure why, but to those who know, If I run the speaker level wires to the audiocontrol processor, which ones am I best to go with. I know others have this setup and well. I need to know via a picture or good description of the best wires to tap and where they are exactly in order to get the signal to the audiocontroller which I can then run RCA's preamps out to the amp then the sub. Thank you all!

WuMu-tien

If no one has a handy 2013 A6 Wiring Diagram, you might consider a one month subscription to Audi's Erwin USA Portal. The portal has wiring diagrams for each vehicle year and type that are quite complete and include the Bose stuff. The relevant URL is: https://erwin.audiusa.com. While this is not directly responsive to your question, it will let you know what your range of choices is for tapping signals sent to/from a given component and explicit wiring paths and component locations.

The portal also has the Audi factory tech bulletins and repair manuals as well, if you prefer to do your own work in vehicle areas other than sound systems.

Papabaehr

I heard the sub wires can be tapped but others on here have said they get better results tapping the rear speaker wires? Not sure why so wanted to know before I do the install. If the signal from the BOSE amp to the sub is intercepted and run to the Audiocontrol line out convertor and there is a built in cross over on the BOSE amp only allowing signals of say 80hz and up through will that mean My aftermarket amp and sub will only be able to produce signals over 80hz? Need someone with some knowledge of our car and aftermarket audio equipment to help....