2015 Volkswagen Passat High Fidelity Audio System – Elevated Audio
OEM Discreet Sub Installed in B5 | Volkswagen Passat Forum
Amazon.com: Add A Bass Subwoofer Amplifier Adapter Interface w/Amp Remote Wire to Factory OEM Car Stereo Radio for select VW Made for Jetta Golf CC Passat EOS Tiguan etc- Vehicles listed below :
Official system setup options thread (Picts and How to Thread) | Volkswagen Passat Forum