Well were talking electronic bass tones here lol, so reproducing accurate sound isnt relative to instrumental bass. So whats clean ???? Also After it's so loud to the ear one of two things happens at 6000Wrms with a DD .. either you can hear how clean it is because your outside the car and everythings rattling, or your inside the car to long and when you get out youll never hear anything perminantly.
So .. If I am in a building and that same DD bumps at 6kw.. as I hear my neighbors all the time lol.. wished I had his //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif It sounds clean to me !!
btw ... electronic Bass + ported box = none SQ setup, so are we speaking of clean as in quality reproduction ??? which with a ported box.. we are sacrificing for efficiancy .
ANyhow.. you hear a DD at 6kwatts for a short period of time driving by your house, and it not only sounds clean but feels clean.