Originally Posted By TheCustomer

At the very least I suspect the system needs a front/rear balance control to get sound from the door speakers.




First, congrats - great colour choice. I'm sure getting the balance sorted will improve the sound you get from the door speakers. But, if the S5 is built the same way as my 'Max then the wires to the door speakers will be the flimsiest twin strand telephone bell wire, not up to the job at all and will chafe through where the plastic sleeving passes behind the door hinge. I binned the factory head unit/amp and speaker cabling, but kept the speakers as they worked better than my ears. If you are upgrading any bits and pieces, take the opportunity to check out the speaker wiring.

Stuart
"There's no skill substitute like cubic inches."