Can I use a Mesa Boogie 400+ with a 6-ohm load? The manual states: (Slight mismatches are not a major problem, but they will cause slightly lower output and may shorten tube life.) If I plan to use this cabinet at a sensible volume, would it work? Obviously it would work, would it be detrimental to the amp? Would 6-ohms close enough to an 8-ohm load? What does running at odd impedance do to a tube amp?