The start of all this was the vacuum operated by-pass flap "Sports Mode" for exhaust noise. (B6 S4) , This made actual noise by by-passing one of the silencers. A variation on this was the exhaust-operated device (Kufatec).
Audi's from 2013 seem to use a vibrating "speaker" device bolted to the bulkhead to give more noise to the occupants. This is operated by it's own electronic module. Currently, cars seem to be using the car's own sound system (speakers) to give exhaust noise to the passengers.
Even some Diesel Cars have this fitted now, so that they sound "sporty"!!
These devices can be de-activated using VCDS.
Personally I find all this ridiculous!
Looks like Pre-facelift has no "false noise" devices.
If you want noise - fit an aftermarket Exhaust System (with increase in bhp too).