On the topic of "input power" vs. output power, I've always been surprised by ratings on various products. Often the "input power" or "power consumtion" seems way lower than I'd expect given the output specs. I guess they do some "average" or "not-running-full-tilt" numbers for input power. Some examples I found:

EV ZxA1 800W Powered Speaker:
Mains Requirements:
100V: 80V–110V, 0.7A4, 50–60Hz
120V: 95V–132V, 0.6A4, 50–60Hz

FBT Maxx 40a powered speaker:
Bi amplified: 500w RMS LF & 150w RMS (650W total)
Rating (back of speaker): 550VA

Yamaha DXR series:
Output power: Dynamic:1100W (LF: 950W HF: 150W) / Continuous: 700W (LF: 600W HF: 100W)
Power consumption: 90W