replaced tape player with cd unit but no sound
 

just picked up a audi concert cd player to replace my tape player and when plugged in and code put in I don't get any sound through the main speakers. can someone help

it most likely needs coding to your car.

If you have Bose and the car the headunit was removed from did not then the pre-outs will be disabled until coding.

Likewise

If you do not have Bose and the car the headunit was removed from did, then the speaker level outputs are disabled until it has been coded to say that Bose is not present.

Coding will need to be done with VCDS.

Does that mean you're getting "some" sound, if so from where, or none at all?

What car have you got exactly and does it have Bose or not?

I get sound on the back shelf but that's it

That's typical symptoms (I should know, read my recent threads! :rolleyes: ) of a Bose-coded unit in a non-Bose car. Back doors too?
You'll need someone with VCDS to recode the head unit (in the car). First research what the settings are. If it was an RNS-D I could tell you, but I gather it isn't.

Don't you know what car you have, or is it a secret? :ROFL:

Edit: This site: http://www.ibiblio.org/tkan/audi/radios/symphony2.html suggests the coding for one model is very similar to the RNS-D.
With VCDS you can see what it is now, typically 00117 or 00017 for Bose. Non-Bose will typically be 00207 or 00507 depending what rear speakers you have (Active or Passive).
As you have "some" sound they're probably Active - try changing the Fader and to see if they get anywhere near reasonable as it is now, by default they're relatively quiet.

I really wanted to keep it standard looking but I think I am going to go down the aftermarket route.
Looking to find a nice flush single din head unit or I might buy the double din centre console to fit a double din head unit.
I also want to upgrade the speakers all round, starting with the rear shelf ones