1995 A6Q- Bose Speaker Problems

[Ti Kan]

Steve Meyer writes:
> There is an aftermarket head unit in the car, but
> factory Bose speakers. I thought at one time you
> couldn't interchange an aftermarket head unit with the
> amped Bose system.

I think your car originally had the Gamma radio, but I don't know
enough about the Gamma Bose system to give you specifics, but I'll
describe some generalized Bose setups and you can determine which
matches your car's system.

On some Bose systems, the head unit has special frequency response
equalization that matches that of the speakers/amp combination.
Replacing that with an aftermarket head unit (with a "flat"
response) would ruin the resultant combined response curve.

Bose speakers generally come in two styles, one has an internal
amplifier, and another style with unusually low impedance and is
driven by a special outboard Bose amplifier.

If your car's setup is the first style, you probably can't simply
replace the Bose speakers with standard units because that would
lose the integral amplifier, and the radio outputs only a line-level
output to it.  The way around that is to add an external power amp and
wire it up appropriately.

If your car has the second style, then you will also need to replace
the Bose amplifier with a "standard" aftermarket power amp, and drive
the standard speakers with it.  The Bose amp has frequency response
equalization that matches with the specific Bose speakers.

> If so can I put in after
> market speakers, do I need to try to find used Bose
> speakers, or just the whole system and re-wire a new
> one?

You can have your Bose speakers and/or amp repaired (depending
on which is at fault).  Try this outfit:
	http://www.carstereohelp.com/
They specialize in Bose car audio service/repair.  I have no experience
or affiliation with this company, but came across their web site and
thought it might be useful resource for some.

> There also seems to be terrible radio reception. I
> have't checked to see if it is just a losse antenna
> connection or are there problems with the antennas
> imbedded in the rear window?

Some Audi radios supply 12V power to the car's antenna amplifier.
Your aftermarket radio probably isn't doing that, so you are not
getting antenna amplification.  I don't have the wiring diagram
for your model of A6 to check, but if you have the family album
you could verify this.

-Ti
2003 A4 1.8T multitronic
2001 S4 biturbo 6-sp
1984 5000S turbo
1980 4000 2.0 5-sp
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