I've got a 400 watt trace elliot V6 all valve amp head that operates at either 4 or 2 ohms I've seen a 800 watt 4x12 trace elliot cabinet rated at 8 ohms for sale which i'm tempted to buy. My questions are:- 1. Is it "safe" to use the amp head set at 4 ohms with the cabinet - will this cause damage to either the amp head or speakers in the cabinet. 2. Will the amp produce less power/output. 3. Currently i use trace elliot 4x10 and 1x15 cabinets both rated at about 300 watts each and both 8 ohms, so together they produce 4 ohms. Will this rig produce more power than using the 4x12 mentioned above? What do you think?