Bose questions for 1989

[Brent O'Leary]

I have an 89 vette with the Bose cassette option. It makes some
horrific high pitched whining sound when the unit is turned on even
without the engine turned on. It also
has a significant amount of engine hum when the car is running. I am
not much of an audiophile, but I find this unbearingly annoying, and was
considering either trying to fix
it myself or replacing the entire system with one of those Pioneer
1.5din CD units and some aftermarket speakers. I have a few questions
and was hoping someone might have some experience with this issue.

1. Is the non-engine related whine most likely related to the head unit
or amplifier/speakers. I assume the head unit as it comes out of all
four speakers. has anyone else experienced this?
2. I assume the engine related hum (alternator whine) is due to the
amplifiers. Has anyone had any luck installing the capacitor type
filters? Is there a central location
to install one, or would I need one for each amplifier?
3. Is it possible to replace the head unit with a newer Delco CD unit
and use the existing
bose speakers? If so, which models are interchangeable? Is it possible
to use newer system with newer bose speakers and use the existing wiring
harness? Anyone know of a good place to buy a delco-bose CD system
removed from a newer model (1990 and up)?
4. If I do go with the aftermarket system and box up the bose system,
what speaker sizes fit in the rear and doors? I don't need subs, and
amplifiers and all of that I usually end up only listening to AM radio
anyway, so a high power deck will be plenty.

If you have any answers or ideas let me know. If I do figure out how to
fix the problem in the existing stereo I will post a summary.

Thanks in advance

Brent O'Leary

[GUTH1]

I have the Bose cassette option in my 89 and have no probs. The unwanted noise
is probably the result of either 1. The unit itself gone bad 2. Someone did a
modification to the unit and it has affected it. In either case, any half
decent stereo shop should be able to isolate the problem.
When you move the sound from speaker set to speaker set, front and rear, does
the problem change? i.e. can you isolate it to a certain speaker? If not, I'd
take it in and get it fixed, unless staying "original" is not a concern.
^^
^^^^^
Las Vegas Sports Flyer
^^^^^
^^

[Ross Carlisle]

If you are not looking for a high end upgrade...I would just send the deck
in for a rebuild. (If infact it needs one) Im doing a system in an 89 now.
Finding the right combination has proven to be a real chore...and a bit
expensive.

Brent O'Leary wrote in message <3727E01E...@worldnet.att.net>...

[Alan Erickson]

On 29 Apr 1999 06:46:21 PDT, "Ross Carlisle" <rrc...@concentric.net>
wrote:

If the Hum or whine is coming from any of the speakers and it varies
with engine speed, then it is a bad capacitor or capacitors in the
power section of the speaker amplifier board. Needless to say, you
will have to pull the speaker to get at the amplifier board and
replace the leaky capacitors. The capacitors are a chronic problem
with the Bose Speakers.

AWE 88

[SHAWN CHAPMAN]

I think what you are experiencing is called alternator wine which is
caused by a bad ground. If you have an amplifier the ground wire should
be no longer than 6 inches and mounted securly to the frame of the car.
I would check the ground to your head unit as well. In reality your
components are "talking" to each other. It would be rather odd for this
to occur in a stock system but if someone has made any alterations or
added amplifiers it is very common. A few sollutions are to ground all
your components to one place on the body, or ground directly to the
negative side of the battery itself. Another area to look is where your
speaker wires or amplifier lead cables are running. Make sure they are
of high quality and kept as far away from each other as well as any of
the cars wiring harnesses. All of the above will keep them from
"talking" to each other.

[Brent O'Leary]

SHAWN CHAPMAN wrote:

> I think what you are experiencing is called alternator wine which is

Should I eat white or red meat with alternator wine?(sorry, I couldn't
resist).;-)

I am relatively certain that the problems I am experiencing are due to the
bad electrolyic
caps on the amplifiers for the Bose speakers. I did a little digging the
other night and it seems these are a big problem on all factory Bose systems
(thanks to all who responded). The stereo is all stock and has never been
modified or replaced. When I get a chance I am going to dust off my
soldering iron and attempt to replace the caps and check the grounds out on
the head unit. If this doesn't work, or if I screw up my amplifiers by
using too much juice on the iron and heating up my components too much,
I have decided I will get one of the Alpine 1.5 DIN CD head units they came
out with this year and box up the Bose until the originality of the car
becomes more important to me than it is right now.