I run the woofer to support my radio in a Smart. The change is not bad compare in any way with the JBL Basspro 2 I have previously operated in an A-class. The Basspro acts like a bass pipe that one blows the trunk. The Pioneer, however, must be as it used to not really built especially in newer cars that have high anyway much better speaker. Anyone who wants to achieve a small improvement this hereby but please do not expect to achieve more.