My reason for asking is that I have a 350-Watt 7-Speaker system with sub. I was wondering what the average was. Isn't it around 150-200 and is 350 good?
What you find stock in cars is between 5-50 watts unless you opt for premium systems. High-end car stereos from manufacturers can output hundreds of watts. There is no hard and fast rule. I would call 350 watts quite adequate. There are people who like big numbers and don't realize the physical limitations of human hearing.