: 98 Eldorado cassette only, want CD!

10-06-08, 04:09 PM
So I'm no audio n00b but I have yet to dismantal one of these cars so I have no idea how its ran and what type of output the head unites have. Now I DON'T have the Bose system but I want a STOCK head unit WITH a CD player..

Is the Bose the only option?

Can I plug in a Bose head unite and leave the speakers stock or would they need a amp?

I'm sure this was asked many times and I been searching the forums but if you could save me some time I'd appreciate it!

10-07-08, 03:42 PM
if thats what you want then i recommend you sell the car and find one with bose as its the only way you can get it to work...

10-07-08, 04:59 PM
wait what?!?!? I cant get the bose head unit and take the speaker outs to a amp? Why the hell not? :eek:

10-07-08, 09:47 PM
bose uses an amp and a brain box to interpret what the hu is saying to the amp
its a wiring nightmare
bose in a non bose car is about as possible as turning your Eldo into a plane

you want the stock look then go buy an ETC or an ESC with the bose option.

10-07-08, 10:23 PM
Option: purchase a 12 Disc CD player on EBay and buy a trunk mounting plate from a GM dealer or on the internet. A few cap screws fasten it on the mount by small holes on the carpet near the mounting boss. It is plug and play using the pigtail that you will find near the right side where the antenna is located. There is a jumper plug in your pigtail that must be removed. Then when you load the magazine and turn on your stock unit it will recognize the trunk mount player. CD's go face down in the player and CD #7-12 can be played by holding down a lower button until a beep signifys a CD higher than six. ie. Hold down button #1 until #7 plays, #2 for #8. The GM model player exist in many other GM cars and I believe Pioneer mfg'd it for GM.

The three volume set of GM manuals detailing this and all other installs can be obtained new from Helm.com in Michigan for about $125 or at a steep discount on EBay or from private sellers on the net. Mine has paid for itself twenty times over.

10-07-08, 10:25 PM
well if you can give me more info like where the "brain box" is located I can grab one and use the lead outs to feed my Slash amps and go from there. I'm a freaking certified electrician for christ sake I think I can handle a radio just give me all the info you have on the brain box and what leads run to it so I can chop the harness and run my own to this box and I'll be golden :p If I could find a cady with the BOSE this would be easy I'd just copy the wiring but none of my local yards have them so I kind if need this forums help if I'm going to get it done.


10-08-08, 12:06 AM
lol, I would just buy a stock headunit that has a cd player and take it to someone with a tech2 if needed

10-08-08, 01:40 AM
thats what I wanted to do but few posts up they say I need a control unit so whats the deal? :banghead:

10-08-08, 10:47 PM
cuz you do...
and its interfaced into the cars data class system

10-15-08, 08:36 PM
Its most certainly not impossible to put a cd player in your car. Its not even impossilbe to put Bose in your car, although it would take a lot of time and work. I recommend going aftermarket, you could use an aftermarket hu and your speakers should work fine. In my 92, which has Bose Gold, I have an aftermarket hu and all the bose speakers work with it. Seeing as how you dont have Bose, it should be easier to get a cd player in there.

10-16-08, 11:18 AM
I would listen to sts .hes the caddy stereo guru around here..never givin me bad info or advice

10-16-08, 05:07 PM
if you want a stock hu with cd player get a bose unit
tap into the speaker wires from it with an loc
run the loc to an aftermakerket 4 channel amp with quad rcas
and in theroy it could work, or not at all bose relies on the data system to interface properly...
i think your much better off with alot less stress going aftermarket, and since you dont have bose its worlds easier to do as you dont have to run new wires and replace EVERYTHING

10-17-08, 11:53 PM
I'd still rerun the wires for the resistance drop in the line but I really like to keep the car looking stock so I'll most likely keep the casset and use the changer option. redo the speakers and add a amp then go form there if the Stock HU quality isn't all that

10-18-08, 08:28 AM
the stock hu is maybe 100 watts rms MAYBE

your expecting far too much from a stock unit imho

cant have your cake and eat it too...

10-25-08, 11:47 AM
Ok guys,

I am in the process of converting my stock 97 STS to BOSE (CadillacSTS2003 knows the deal). First of all everything he said makes sense: IS REALY HARD to do the conversion, here is why:
On a stock system the HU is the one doing everything, the audio output goes straight to the speakers. On a BOSE system the HU is just part of the system, it is only there to house the radio, CD player, Tape and Chime. The BOSE HU only has a two channels stereo output for the audio (CD/TAPE/Radio) and one mono for the Chime. The audio signal goes to the second important player in the system the RIM (Radio Interface Module, called like that mostly for historical reason, the real name would be Sound Processing Module, but let’s stick with the GM nomenclature). This RIM is accepting as audio input signals: the 2 Ch. Stereo signal form HU, the Mono Chime signal and the 2 Ch. stereo signal from the CD Changer. These channels are processed by the RIM and split on 4 output channels – one for each speaker. At this point the signal is also volume control dependent. Each speaker has its own amplifier (one single channel amplifier for each).
Enough with sound, now let’s get to controls:
We did not mention one extra member of the sound System: the steering wheel controls module (part of the Instrument Panel Cluster) and ah yeah the Cellular Communications Module (for who ever will use-it).
All these devices except the CD Changer are part of the car data bus network; this is how they communicate with each other. On the other hand the CD changer is just a slave of the HU (although for the BOSE system the output of the CD changer is going o the RIM rather than back to the HU just so it makes thighs more complicated).
Let’s start with the HU, he is the one doing most of the work: CD\CD Changer control, Tape, and Radio. I have just one thing I am not sure about, and I believe (for the moment) that the volume control function if not handled by the HU as it is in a base system. Why do I believe this? Simple: the CD changer audio signal does not return to HU but rather goes to the RIM (remember?) and the question is: who is controlling the volume for the CD changer? Well definitely not the CD changer himself since the same unit works in BOSE and non-BOSE systems and we all know the HU controls the volume in the stock systems (the CD changer has just a constant line out signal). So using this logic I would have to disagree with CadillacSTS2003, an aftermarket amplifier can not be used unless it had a volume control feature. The BOSE HU provides just a constant line out audio signal (the same as the CD Changer). With my logic the BOSE HU acts just like the Steering Wheel Controls Module sending commands on the car data bus (like Volume UP/DOWN, and so on). The RIM does the actual volume control based on the commands received from the HU and steering wheel controls. Also, think about the treble and bass settings, is the same as with the volume. It is very strange why the RIM is not just a slave of the HU (same as the CD Changer) but rather is a device of equal rank with the HU part of the car’s data bus. It will make all the sense in world to be a slave…huh.
Ok now the RIM, he switches the input signal between the audio signal received from the HU and the one from the CD changer based on the commands received on the car data bus from the HU. The HU switches the output signal (sent to the RIM) between CD/Tape and Radio based on the buttons pressed by the user. The magic thing the RIM does is splitting the two Ch. Audio signal received (from either HU or CD Changer) in 4 based on a algorithm that takes in consideration the balance, fade and DSP (Digital Sound Processing) input. So the signal in any of the speakers can be delayed (and based on the delay you get all the sound effects). Speaking about DSP I have yet to see one single car equipped with this particular feature.
Also the RIM mixes over the regular audio signal (HU or CD Changer) the Chime (sent to the FL speaker). This signal is not volume dependent.
At the point when the audio signal leaves the RIM it is already volume controlled. Another attribution for RIM is controlling the power for the speaker amplifiers thorough two relays (one for the left F/R amplifiers and another for the right F/R ones).

So conversion, conversion…
hah, is not simple, not simple at all, the harness is COMPLETELY different, you need to:
- Change the HU (easy);
- Run extra wires to the HU;
- Change all 4 speakers;
- Run power wires to the speakers (for the amps),
- Add one extra fuse to the car fuse cluster (well the fuse alone is not a problem but you need to do the wiring too);
- Add the amp relays
- Add the RIM;
- Even the CD changer has to be rewired.
The only things left untouched are the power antenna and steering wheel controls, a looooooooot of work but I’ll do-it..

10-27-08, 03:16 AM
so I just need to hunt down the RIM and figure out the harness wiring and the rest is a cake walk :p Ill forget the Bose shit after the rim splice in my amps and be merry! :lildevil: