Rob wrote:

Hey guys, looking to fit an aftermarket HU into my audi A4(99/00)
now as far as i'm aware there is 2 seperate wiring loom adaptors
available one being rca the other being non rca

I'm guessing your A4 is the Mk1 (B5) shape. Not 100% sure about this as
both my current and previous cars have been the MkII (B6), however I
previously had a 1999 A3 which used the same connectors so it's pretty
likely an A4 the same age would also be the same.

On the standard system, the rear channels are amplified, with a sub
mounted in the rear deck (or behind a panel in the boot in the A3 or A4
Avant), with the fronts being driven from the head unit.

The Autoleads adaptor connects to the rear line outputs and amp remote
connections on the head unit. However, the output level from the stock
head unit is considerably higher than on an aftermarket unit (it's set
up this way as it has to drive a long run of cable down the length of
the car), so you've got 3 choices:

1. If you're running the fronts off the head unit, set the fader towards
the "rear" position so the fronts drop to match the rears.

2. If you're running the fronts from an offboard amplifier, decrease the
gain on the amp to match the rears.

3. Fit a line driver such as a Vibe DeltaBox between the head unit and
adaptor harness.

Option 3 is the best (particularly if you're not using an offboard amp)
as then you've got the full range of volume control available.

The only problem I've found with the MkII A4 (and MkIII, not sure about
the MkI as I can't remember where the rear speakers are located) is that
unless you drop the level of the rears by 3dB you can hear them louder
than the fronts, as the tweeters in the rear doors are right behind your
ears. Unfortunately this also drops the sub level as well.

I've solved this by fitting a pair of 10" JBL subs in the boot... :-)

--
Glenn Richards Tel: (01453) 845735
Squirrel Solutions http://www.squirrelsolutions.co.uk/

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