Tower Audio recently upgraded a Subaru WRX with a Pioneer 9-inch AV head unit, matched with a high-power amplifier and custom-tuned subwoofer. The goal was simple – deliver sharper detail, deeper bass, and modern smartphone connectivity while keeping the factory look intact. Why the Pioneer 9-inch system suits the WRX The Pioneer AVH-ZL9150BT 9-inch display fits perfectly into the WRX…