Thinking about getting one of these, along with a Walkabout head. I play a Warwick thumb 5-string. Mesa Boogie's web site doesn't have much technical information on the Powerhouse cabs, though. Can anybody answer these questions -- 1. What's the low frequency rating for the PowerHouse 4x10? If I play just through the 4x10 will it handle the low B? 2. Is there a tweeter or horn on this cab? thanks in advance.