Right, I have a McGregor Bassman 200W head and it has 3 outputs, Ls1, Ls2 and Slave. Above these it says 'minimum 4 Ohms'. I am currently using two Carlsbro 150W 1x15 speaker cabs from school. They are 8 Ohm. They have In, Out and Link sockets. I'm using one cable to each cabinet into the 'In' socket from Ls1 and Ls2 of the head. How many Ohms would this equal? Am I completely destroying the cabinets or the head? Would I need a cable splitter from Ls1 OR Ls2 to both cabs to get a 4 Ohm load? Thanks.