I have recently bought this head unit to replace my Becker unit, due to MP3 play back. I have wired it to my car, but i have a problem. It states that if you change the settings on the stereo from 4x40w to 4 x 60w, the earth wire has a ring terminal and has to be earthed to the chassis. The guy who fitted it for me says that the 4x60w will result in loss of sound quality, but if you keep it at the 4 x 40w setting, you don't need to earth it. Is he talking out of his ***?
The unit is actually quite good! It has a clean, crisp sound, the Becker was a more warmer sound, but the pioneer plays MP3's and has an EQ, low pass and high pass filters etc etc
if the earth wire is the ground wire, then yes I grounded mine anyways. I just felt I was better safe then sorry.