As per PM, all non Bose 8L's have the same speakers, 4" components in the front and 6.5" coaxials in the rear. They are all 4 ohm impedance and are specific to the 8L (no other Audi models use them). Bose was still a £500 option on the S3 so not standard on any 8L. With the Bose setup the speakers are 1.5ohm impedance so even if you can find 2ohm aftermarket units they will still suck less power from the Bose amp so you are better off sticking with OEM if one is blown or crackling.