so i tried googling and searching all around on writeups and such on how to install subs on b5's and i just cant find any legit how-to's. from what i see, you gotta get a hi-lo converter and tap it to the stock amp... but i have a couple questions on this... how exactly do i know which wires are which? if i tap into the left and right of the rear speakers will that kill my rear speakers? i want all of my speakers working and if tapping will make them not work then that would be a bummer... also whats a good spot to route the power cables? the audio store is charging 160 to install it for me but i just hate the feeling of others working on my baby... i dont want em to break a kick panel or something trying to route the wires... any help would be appreciated thanks guys

 

What you need is a frequency converter, one that converts to lower frequencies, then hook up the converter wires to the rear speakers, you might only need to do one speaker or both rears depending on what converter you get. Just splice into the wires of the speaker, don't cut them if you don't have to, then hook up the + of the converter to the + of the speaker and the - of the converter to the - of the speaker. Then you need to run rca cables from the converter to the amp you bought for your subs, then hook up the subs to the amp. Then remove the lower door panels on the front and rear doors then run the power wire up to the front and through a gromet in the firewall, then ground the amp to a good ground somewhere in the trunk, then run the remote wire through the same spot you ran the power wire and hook up the remote wire to the positive wire of the headunit, stock radio. Look up the wiring diagram for the stock radio and see which wire is the power wire for the stock radio and splice into it and connect remote wire.

 

Here is a link to a DIY I did a few years back.

Amp & Sub install

Doug

 

thanks... would tapping into the speakers kill the speaker tho? like you said in your write up u should tap the the drivers rear speaker... but will that kill the speaker ur tapping into or is the speaker fine?

 

tapping into speakers won't kill the speakers its going to distribute the watts evenly and all the speakers will be under powered. also going to the dealer to have them run a power cable? seriously? If you can't run a power cable from the battery to the trunk you shouldn't be touching anything else.

 

^ LOL.

Running power cable is probably the least you'll have to worry about when installing a subwoofer. Its as simple as hooking up the cable to the battery and finding a way/hole to go through the firewall into the cabin.

 

There is a hole,going through the firewall under the driver side foot well. I ran my power fire for my Pioneer head unit,through it.

I had one problem,though. Water was coming through the hole,every time i got a car wash,water and suds were on my A4 weather rubber mats.

I think the water was traveling,on the power wire and dropping on the mat.

I put some rubber glue,in the whole,to cover up the gap. That solved the problem and haven't had any water or suds,leak through that hole,ever since.

 

lol sorry guys... i ment audio store not audi store... and yes i know how to wire the power and what not... i am a mechanic i work at a shop (for a year now) and im not that retarded... my question was how to install the hi-lo converter... but its okay now though because i had the audio place install the hi lo converter for 30 bucks... i wired the power cable into and through my ecu box and into the left driverside panel ... under the kick panels and to the back seats and i mounted the amp on the back of the rear seats... took me about 20 minutes to route everything. sorry for the confusion guys lol

 

Where you are tapping is actually before the high level speaker wire where it is still a low level signal or RCA voltage. If you are not convinced take your deck out and have a look at the back and you will see a diagram like this with line out.



These wires are the exact same wires on the connector leading right from the back of the deck all the way back to the rear speaker, where it is a pre amp or low level signal. This is where you tap in and NO you do not need a line level converter.

Like I said in my DIY post

"You don't need a high to low level converter as there is already a low level signal at the driver's rear speaker that you can splice into. If you use a line converter you are taking a low level signal from your head unit, converting it to a high level signal through the stock amp, then converting it back to a low level signal with your hi-low converter, then converting it back to a high level signal through your new amp to your speakers. If you hook it up with the below method, you take a low level signal from your head unit and your new amp converts it to a high level signal for your speakers eliminating 2 conversions which introduce signal degradation and distortion. So there is no need to tap into both left and right speakers as all the connections are located on the driver's rear speaker."

If anything it will hurt sound quality let alone cost you whatever for the part and $30 to install. If the above statement doesn't convince you to not use one then I give up.

Doug

 

thanks doug... i appreciate the help!