Keech

I have installed an Alpine CDA 9857 in to my Audi A4 B6 replacing my failed non-Bose, non-Nav stock head unit. I used this adaptor from <a href="http://www.autotoys.com/x/cust/product.php?productid=1194#"> autotoys </a> to connect the head unit to the amp which powers the sub and rear speakers as well as connecting to the front speakers. The settings on the head unit only allows power via the internal amp or an external amp, not both. As a result, I am getting power to either the front speakers or the rear speakers at one time.

As I see it, my two options are installing a two channel amp to power the front speakers or buying a different head unit. Of the products I looked at in the Alpine line, all have this same on/off feature with the head unit. Is this common for all brands? I have owned home stereo equipment which would allow both the usage of a receiver's internal amp in conjunction with an external amp. Are there any other options? Can I re-wire something to make this work?

Thanks in advance.
Keech
BTW, I have for sale a blitzsafe adaptor (RCAs out) for an iPod if anyone is interested.

avincar

I interpret what you are saying as "the Alpine HU allows me to turn off the internal amp".

However, Alpine has been supporting deck-AND-amp systems since around 1984 (then called 'Bi-Level" on the faceplate of 7273 cassette decks and the like).

Are you certain that with the internal amp on, you get no output to the rear speakers on the speaker wires?

As another test, do you get audio from all sources? A common problem in your scenario is crossing up Alpine's blue and blue-white wire, which means that the rear amp only turns on with radio and not CD. This can further goof up your testing and make your results seem crazy.

HIS4

I agree with avincar that this may be due to installation error. The power antenna lead is a good place to start.

Keech

There *is* sound coming from the rear speakers but at such a low volume I couldn't hear it. I don't think the sub is working at all though.

I was looking at the manual which explains to turn off "Power IC" when connecting an amp, so I assumed they weren't working, along with the low volume. Is the mismatch in volume typical in situations like this? I have to set the fader to -7 (out of 15) to get a balanced sound. I have no experience in after market stuff in autos.

The speakers are stock. I do get sound from all sources: tuner, disc, sirius, and iPod.

Thanks.

MacSub

You'll have at least twice the power going to the fronts compared to the feeble 2 x 20w going to the rears via the Audi amp, so there will always be a big imbalance. I just ran the rears off the HU, amped the fronts and added a stealth sub behind the rear boot panel. Completely removed all the Audi garbage. Now sounds excellent.

Keech

Did you run new wire to the speakers I am not sure how those are wired or where the Audi amp is located.

MacSub

so the amp is bolted to the tupperware sub in the righthand cubbyhole, presumably it's similar on the saloon.
I can post the wiring pinout if you need it, but it might be different on the saloon. I had to trace them back to the rear door speakers to find out which was positive &amp; negative, but I think the speakers are in the rear shelf on the saloon so it should be pretty straightforward?

Keech

so knowing the amp is near by is very helpful. Thanks again.

Heyrenzo

... and bypass the amp altogether?

MacSub

and you are fitting an aftermarket HU (as the Audi HU as no internal amp for rear speakers).