I'm a total newbie to head and cabinets so i'm hoping some'll help me out here. What i want to know is how does the wattage of a head relate to the speakers. Suppose i have a SWR 2004 head. What kind and how many speakers could i hook up to it? And what would the result be? not in terms of tone but total power. Would it be louder with 1X15 and 2X10 or would it be the same with just 1X15? What's the difference between 200W at 4 ohms and 160W at 8 ohms? What's the maximum ammount of speakers you could hook up to it?