The three π subwoofer uses a 12" woofer in a bass-reflex cabinet tuned to 20Hz. The 12 π is basshorn subwoofer using two 12" woofers with external heat sinks and push-pull drive . Driver Complements
In fact, turn the volume all the way up just for checking: your speakers might be working but playing weak sound. Make sure that the correct playback device is enabled in your operating system. The operating system might be trying to play the test audio through a different device or jack.