Look, I know we're Bonneville guys here, but I ran into this problem back in March, and posted on clubgp, but nobody replied. I guess first I should ask, do Bonnevilles come with the same Bose system that the Grand Prix has as an option? (My wife'* is a 2001 GP GT).

If so, I was considering keeping the factory head unit, but replacing the Bose amp and speakers with aftermarkets. Ideally I'd wire the new amp up to a factory-compatible wiring harness connector that would plug into the factory harness exactly as the Bose amp did, -but nobody makes an aftermarket harness for that connector. I suppose I'd have to get another Bose amp at a salvage yard just to chop the connector off it.

Even so, I question how the Bose system powers the front speakers. They are wired from the HU to the trunk amp, back up front to the doors. But are they really powered by the trunk amp, or do they just pass through the trunk amp unchanged?
-Nobody has been able to answer that.

I ask, because there are conflicting reports that the Bose Amp only drives the rear speakers, and that the HU provides the current driving amplification for the front speakers. But if that is so, I don't understand why they'd bother to route those wires back to the Bose Amp in the trunk, then back to the speakers in front.

Also, I think there is an error in the wiring diagrams for the factory bose system:
The description for pin 11 on the HU says "Speaker Return -Left Front"; but the HU does not directly connect to any speakers, and there is no corresponding "black+white" wire on any of the speakers or the Bose Amp. This looks like an error to me.
Connector diagrams here:


http://mywebpages.comcast.net/alitak...x/audio.html#5

the Bonnes did come with BOSE in the 97+ models.

you just go with line level converter for a aftermarket amp, and them into your speaker leads....

Im not familiar with the BOSE in the GP, but it would seem that the BOSE amp would power all the speakers in the GP

Whoa, check this out. Pacific Accessory Corporation sells a device that plugs into the factory harness to add an amplifier (or completely replace the factory amplifier) that sorts out all the wiring headaches. Looks like *JUST* what I was wanting!
http://www.pac-audio.com/oem1kits/ao...or+AOEM-1+kits

I'd agree you found the answer!

I had a caddy seville with Bose system

The speakers were integrated into the panels and sold
as units like that. Amp/speaker panel inserts. Bose
is notorious for very low ohmage (seen 2 ohm drivers)
custom notched amps to drive them....

ANY audiophile worth his salt cant stand them and you
couldnt give me any 5.1 home theatre bose crap
but (most ashamed'ly) I run 301 series IV '* as rear
speakers in my home theatre. Just cant find decent
bookshelves with 8" drivers.

Anyway Bose speakers/crossovers are very decieving
and use a good deal of electronic trickery to avoid peaks
- and distortion..... very tricky

The caddy was about impossible to rid myself of it so
it was live with it - the newer GM'* seem to be more
favoriable for the hacking.... Good Luck!

The 97-98 Grand Prixs with the premium sound (Bose wasn't an option until 99) had an amp under the package tray that powered the rear 6x9s (low passed) and 4" (high passed). The door speakers were directly powered via the head unit.

Bose equiped cars use 2 ohm drivers all the way around, and all are powered from the bose amp. If you want to replace the speakers in this car you will have to use aftermarket amplification using either high level inputs or installing line output converters/factory amplifier integration piece. I personally would suggest replacing the head unit along with the door and 6x9 speakers. You have the option of running new leads to each speaker and leaving the factory wiring unmoddified, or bypassing the Bose amp (can be done various ways depending on how crafty you are). When I run into this situation when working on a customer'* vehicle I typically use an aftermarket wiring harness(es) and re-pin the leads in order to build an amp bypass plug. Keep in mind you only want to discontinue use of the Bose amp if you looking to replace the speakers with non-factory equivilents.