Audi S4 and BOSE wiring

prophet · 04-11-2004, 09:39 PM

Argh. I just typed up a nice description, only to hit the back button on my mouse by accident.

Here we go. Again.

I'm working on an 2001 Audi S4, with the premium BOSE sound system.
I removed the stock head unit, and replaced it with a 7" Touchscreen Liliput LCD.

The LCD works very well, and I have no complaints.

My question is that of wiring.
I purchased a 360W Alpine 4-Chan. Amp, and a subscription to Bently Publishing's Wiring Diagrams for the S4.

I used wiretaps on the wires used by the stock speakers, and ran new wire into the trunk, where the amp is.

I connected the speaker wires to the amp, and a remote wire (+12V) from the stock head unit's wire harness.

After all of this work, I realized that the amp. installation kit I had baught didn't come with (or I had managed to loose) the 8 gauge wire crimp used to connect the power wire to the amp itself, and the ground wire to the amp/ground surface...
Anyways, today was Easter, so nothing was open - I'll wait until tomorrow to buy the crimping connectors... but before I do all of that, I want to get some people's opinions:

Will this even WORK with the stock BOSE speakers?
Has anyone does this before? If so, which wires did you use to tap off of, and run new speaker wire?

*also*
Where the heck is there an existing hole in the firewall, where I can I feed the power wire from the battery of the car, to the trunk for the amp? I've had no luck finding anything! Drilling an S4 dosn't sound like such a hot idea to me...

Any comments or suggetions would be great!
Feel free to email me:
prophet@scrapcode.com

Thank you all very much,
-Bradley.

cdm · 04-11-2004, 09:49 PM

if your bose is anything like my nissan's no. bose speakers use a 1OHM resistance that you must match before they sound anything decent. of course, you could have "normal" bose speakers that will work right in. try and see but be prepared for failure.

prophet · 04-11-2004, 10:00 PM

Yeah. I've heard of the OHMs on the speakers casing horrible problems - but I'm not too sure if it will with this setup.
If there is a conflict, will I blow the speakers?
I'm trying not to destroy anything

jojor512 · 04-11-2004, 10:27 PM

the audi S4 is one of the more difficult cars to do an install in. There is no hole in the firewall to pass a wire through, and the engine bay is very packed & hard to work in. You'll have to drill a hole, good luck not hitting anything. Might want to look into having a proffesional do it if you're not comfortable, i know we all hate admiting defeat but its not worth drilling into your S4 unless you know what you're doing. Don't even think about trying to get power from the fuse panel...

prophet · 04-11-2004, 10:41 PM

Definatly wasn't thinking about the fuse panel.... heck no.

Yeah - I suppose bringing it to a professional installation place would be our best bet. I most definatly don't have a drill that powerful / sharp, nor do I have the motor skills to steady my hands while drilling the hole.
I have enough trouble taking panels off the car, let alone drilling!

Thanks a lot!
Any other suggetions would be great!
Thanks.
-Brad.

jusatry · 04-11-2004, 10:52 PM

Quote: Originally Posted by prophet

Definatly wasn't thinking about the fuse panel.... heck no.

Yeah - I suppose bringing it to a professional installation place would be our best bet. I most definatly don't have a drill that powerful / sharp, nor do I have the motor skills to steady my hands while drilling the hole.
I have enough trouble taking panels off the car, let alone drilling!

Thanks a lot!
Any other suggetions would be great!
Thanks.
-Brad.

NEGATIVE GHOSTRIDER!

you can do this. If your S4 is anything like my A4 (engine aside

), there is a distribution block under the knee bolster on the driver side. It has 3 bolt connections on my car - and there are a good number of low guage wires coming in from the engine bay already. I would just reccomend not tapping a nut that has a lot of wires already (we assume thosre are important).

Hope that helps - post back with results!

jusatry · 04-11-2004, 10:54 PM

Quote: Originally Posted by cdm

if your bose is anything like my nissan's no. bose speakers use a 1OHM resistance that you must match before they sound anything decent. of course, you could have "normal" bose speakers that will work right in. try and see but be prepared for failure.

In my 2003 A4 running the sonica theater on 4 channel sound into the BOSE amplifier line in feed sounded great. I was worried before i did it (impedence and all), but it turned out great!

just letting everyone know, bose isnt has hard as it seems

prophet · 04-12-2004, 04:45 AM

Wow. This is the first thread I've seen that actually has people with some GOOD bose stories!

jusatry,
how did you wire your system?

jojor512 · 04-12-2004, 11:31 AM

Quote: Originally Posted by jusatry

NEGATIVE GHOSTRIDER!

you can do this. If your S4 is anything like my A4 (engine aside

), there is a distribution block under the knee bolster on the driver side. It has 3 bolt connections on my car - and there are a good number of low guage wires coming in from the engine bay already. I would just reccomend not tapping a nut that has a lot of wires already (we assume thosre are important).

Hope that helps - post back with results!

um terrible idea, please don't say stuff like this because someone will do it........................................... If you connect anything to that panel there's a good chance you will overload your audi electrical system which can get very pricey to replace. Those connections are not designed to hold anything remotely powerful. Believe me on this, any and every installer will tell you this, as will any audi dealer. You need a DIRECT connection to the battery. Three's a lot more going on in your described "block" than just distributing power.

prophet · 04-14-2004, 02:09 PM

The speakers are installed. The amp is hooked up (after a lot of problems with the remote turn on wire)

I'll post soon with installation pictures, and detailed instructions - because it seems as if there arn't any real good FAQs on Audi BOSE systems and using the stock soundsystem with an aftermarket deck or a CarPuter.

Anyways, for those of you just looking now, I'll give you the setup:

My goal was to keep the BOSE speakers in the car, and to install a carputer, with a LCD in the dash, controling a laptop in the trunk.

Apparently, this is a contraversial thing to do. Every audio installation place I went to had a different opinion, including online forums, too. Some say "Of course it can be done.", others say, "Don't even try - it will NOT work, the OHMs are wrong.", and some even say, "If you do it, it'll work, but sound horrible. You'll get popping, scratching, and all sorts of distortion - don't waste your time.

This is not true. The 2001 Audi S4 has the premium sound system, and works VERY well with the laptop I installed. I did, however, have to install an aftermarket amp. This might not have had to happen, too - but I figured it'd be a good thing to do since the BOSE speakers have amps of their own, usually one per speaker.

I didn't want to fiddle with THAT much, so I figured giving the speakers power the "normal" way was my best bet. The amp I chose was an Alpine 360W 4-channel Amp.

I tapped into the speaker wire coming into the car from the doors, using wire taps (pick some up at radio shack), and ran the new 16 gauge speaker wire to the amp in the trunk.

In a later post, I'll include the wire locations, and the wire colors - but I can't recall them off the top of my head, and I don't have the wiring diagrams handy at the moment.

The remote turn on wire for the amp was a REAL hassle. I looked at some documents online that said some white wire, or some purple wire were the switched +12V power source that an aftermarket amp needed to power on.
These wires did nothing for me. It took a good couple hours to sift though all of the wiring diagrams I had printed out from Bently and find that there was a +12V wire going into the stock head unit only powered when the car is running (switched)... That wire, as I remember, was a semi-thin RED AND BLACK wire - which wasn't even labeled on the diagrams on the forums. I gave that wire a try, and connected it to the amp - it worked wonders!

The system is nearly complete - all of the speakers work perfectly fine, with the exception of the subwoofers. (I believe I tapped the wire in the wrong location for their use...) The sound quality is still BOSE - exceptional, in my opinion. Loud as anything, and clear as hell.

Stay tuned for a REAL detailed guide, and a bunch of pics that my friend and I took during the process. (we plan on making a cardboard childrens book of the both of us messing around, eating bondo, and mounting LCD screens... =D )

jusatry · 04-14-2004, 03:05 PM

Quote: Originally Posted by jojor512

um terrible idea, please don't say stuff like this because someone will do it........................................... If you connect anything to that panel there's a good chance you will overload your audi electrical system which can get very pricey to replace. Those connections are not designed to hold anything remotely powerful. Believe me on this, any and every installer will tell you this, as will any audi dealer. You need a DIRECT connection to the battery. Three's a lot more going on in your described "block" than just distributing power.

Well I had heard from many a source that the dist. block was safe to use, and nad i have been using it for my subwoofer amp for 5 months now with no problems with the elc system......which i had an installer do. Have you had personal exp with friends or something that had problems? If so i would like to hear about it. What if i used a capacitor in the trunk, would that help? I guess i could re-run 8 guage wire from the battery again, but is there a hole in the firewall? Anyway, please post back with more specifics - i would love to hear them.

infinkc · 04-15-2004, 12:08 AM

ive wired a few bose systems up in audis before, ive used a sound adapter to lower the levels of the inputs to the speakers and using an aftermarket amp and that has worked well, also i have directly used the bose amplifer inputing low level to it and that has also worked. the best way still is just to change out the speakers and use an aftermarket amp.

jusatry · 04-15-2004, 12:27 AM

Quote: Originally Posted by infinkc

ive wired a few bose systems up in audis before, ive used a sound adapter to lower the levels of the inputs to the speakers and using an aftermarket amp and that has worked well, also i have directly used the bose amplifer inputing low level to it and that has also worked. the best way still is just to change out the speakers and use an aftermarket amp.

hey infinkc -

whats your take on the dist block thing? You think its unsafe or unwise to wire power from there?

Thanks!

brrman · 04-15-2004, 10:05 AM

Quote: Originally Posted by jojor512

the audi S4 is one of the more difficult cars to do an install in. There is no hole in the firewall to pass a wire through, and the engine bay is very packed & hard to work in. You'll have to drill a hole, good luck not hitting anything. Might want to look into having a proffesional do it if you're not comfortable, i know we all hate admiting defeat but its not worth drilling into your S4 unless you know what you're doing. Don't even think about trying to get power from the fuse panel...

You can send your main power line through a grommet in the ECU box (which I did with no problems whatsoever) or the grommet that the hood release cable passes through. Anyone who has had to drill through the firewall in an S4 or an A4 has not done enough research into alternate possibilities.

Quote: Originally Posted by jojor512

um terrible idea, please don't say stuff like this because someone will do it........................................... If you connect anything to that panel there's a good chance you will overload your audi electrical system which can get very pricey to replace. Those connections are not designed to hold anything remotely powerful. Believe me on this, any and every installer will tell you this, as will any audi dealer. You need a DIRECT connection to the battery. Three's a lot more going on in your described "block" than just distributing power.

uh - that's absolute bull****... sorry. Two posts on that dist block ARE direct connections to the battery. The only one that isnt is the x75 post - which is switched power.

Quote: Originally Posted by jusatry

hey infinkc -

whats your take on the dist block thing? You think its unsafe or unwise to wire power from there?

Thanks!

The dist block under the knee bolster has 3 main bolts. One is the 75x bolt - thats switched power, only on when the ignition is on or the key is in accessory position. The other two are constant power direct to the battery.

I have wired several things (remote lead, eq, boostgauge, auto dim rearview mirror) to the 75x post with no problems. Just make sure you fuse any line that you add to it, just for safety.

I would not run a a series of amplifiers off of it though. Better to do the traditional setup with 4-8ga wire from the battery so you have the added mainline fuse and an appropriate size gauge wire.

infinkc · 04-16-2004, 08:31 PM

i prefer wiring it directly to the battery if possible, the audi isnt that bad if you run the power thru the ecu box and out that gromet. Ive ran the power into the hood cable gromet, but the ecu gromet is 100x easier to do and cleaner since its closer to the battery. If you use the fues block terminals just be sure you correctly fuse whatever you hook to it, and make sure its not going to draw more than it can be rated to.