Hello chaps, AndyMac helped me loads with a speaker upgrade in my old S3 which I have reciently sold. I have just bought a 2003 S4 without Bose and am wanting to carry out a similar stealth sub/amp upgrade. I've been searching the forum but can't find the info I'm after... At the rear amp, on top of the o/s/r wheel arch, which colour wires go to the rear door speakers? I've bought the BP RCA preout lead as eventually I want to amplify my front door speakers too. I'm planning to replace the sub in the rear parcel shelf and add an amp. Can anyone recommend an amp (at a reasonable price)? I used a Kenwood last time partly coz it was a good price. It made a huge difference. Any help would be much appriciated Thanks in advance Antony.