On a subwoofer in a home theater setup, I have heard so many different theories regarding what calibration dB it should be at or near; I am told by Terrence that it should be 4 to 5 dB HIGHER than what all other speakers in the system are, while some tell me that a couple of decibels higher is all it needs to be....my main and surround speakers are on "+6 dB" on my receiver's calibration, and my center is on "+8" to compensate for dialogue, while the sub is also on "+6" because any higher and I am experiencing a loud "cracking" or "snapping" noise from the sub during extreme bass peaks on DTS and DD EX soundtracks; if all other speakers are on "+6" (the mains and surrounds, that is), should the sub be bumped to like "+10" if that is the theory?