I have these on all 4 doors powered by a Alpine KTP-445U amplifier. Sound clarity is good. I get no bright nor harsh tones from the tweeters. Voices are clear with no muffled sound. My amp gains were adjusted to my deck's output using a SMD DD1. The description of these speakers is correct: you will think you have a small subwoofer in your car.
Bass from these speakers is impressive. I sealed all openings on my doors with sound deadening material. I'm using 3/4" MDF mounting brackets and I also have foam padding behind the speaker and the inside door frame. These modifications has greatly improved bass and mid-tones by eliminating sound distortion caused by hollow doors and road noise.