I'm not a scientist so please take whatever I say with a pinch of salt, but I've played both this amp and an Orange Terror (allegedly 1000 watts) through the same cabs at various venues and I've never noticed any loss of volume/power/output/headroom (call it what you will) when using the Bugera. Doesn't bother me what numbers the marketing people choose, it's lightweight, pretty, versatile and sounds great