Hey guys

I'm planning to add a new sub using the wiring from the rear 7" subs (non-Bose system) on my '96 A8Q

ive read through some of the older posts of people who intalled custom subs and i have a few questions.

What do you guys suggest

Option 1

BTX 250 (2 10" subs, amp and crossover with controls) package tube sub

Option 2

CS-1200T tube Sub
Soundstream 2ch. Amp
custom wiring
crossover (Required?)

Options 3

Your suggestions?

Questions

1) Audi Radio code - is the radio code a 4 digit number? Nothing metioned on the radio card but a CD changer authorization number and another 4 digit number mentioned on the service booklet

2 How do i get all the bass to the sub instead of it beign reproduced along the other speakers?

3) Does the existing(non Bose) system have a built-in crossover ? if so where would it be located?

4) Jacobs has a product that can be connected ot the exisitng wiring to add an RCA Audio in to the system. i need this for the new Capruter ive built. Although im a little worried about the port of the VAG controller. Will there any problems if i splice the wires? I believe there connected in some way.