How would you characterize the sound quality of Rumble Road speakers?

MHI’s high-output, high-fidelity Rumble Road™ stereo speaker system produces crisp, powerful sound even at highway speeds. The current-generation Premium amplified and Limited non-amplified systems deliver powerful, clear audio response. The Premium produces 46 watts peak power per channel into highly efficient 4-inch RCA coaxial speakers. For both models, our quality speakers are large enough to create good bass response. In particular, the Premium model's custom amplifier and overall packaging generate an impressive range of sound.