Audio Systems: Speakers, electric antenna, audi a4

Question
Hi, I recently purchased a new car stereo for my Audi A4...i removed the factory one fine. I was installing my new one and found the speakers wires are not clear to where they should go, after figuring it out slightly i started to wire it up only to find i have no noise what so ever?! I got an old speaker from my house and linked the wires from the new stereo to it and it worked. i'm thinking there is an amp somewhere thats gone or something but it's hard to see where it could be. Ivwe checked in the manual but no joy...can you help?

Answer
you know all the a4 are not the same they made that vehicle  90's to 2008

there is nothing wrong with the amplifier you just need to turn it on use the blue wire of the new radio for that   you also need the electric antenna cylinder   and wire it to the same blue wire all 3 together  

good luck