Can you connect a combo (mine has an ext output) amp to a cabinet or should it be speakers? Well the combo amp sound better through the speakers or cabinet? What is the difference between speakers and cabinets?

Nothing. They call it a cabinet because it's solely for the speakers. There should be stereo outs or or something like that on the backof your combo amp. It should sound better with the cab plugged in.

__________________

My randall amp also has the output for a cabinet. Sounds better indeed

__________________