No, that's just the maximum capacity of the speakers. You can always run them at less than their maximum rating.
The sound quality isn't determined by the amount of power it can handle, in this case, 400 watts. What determines the sound quality of the speaker is the design of the speaker itself.
It is possible that a 600 watt amp could be louder than a 400 watt amp when paired with 400 watt woofers, but it also depends on other factors like speaker efficiency and the overall quality of the components. More wattage generally means more power and potentially more volume, but it's not the only factor that determines loudness.
watt rating of a speaker is max power it can handle without getting damaged. it will produce proportionate amount of sound for less power from amp., even for 1 watt.The power output ratings for most amplifiers are very misleading. That number,i.e.,1000 watt , is under one certain type of condition for 1 second. Usually the frequency of 1khz for 1 second. The true output under actual operating conditions 20hz-20Khz is probably closer to 100 actual watts of music power or sound reproduction power. The same with the speaker rating,,,the power rated is at the same conditions Max power @ certain frequency @ certain amount of time.Safest bet,,,,,always use a larger rated speaker for an amplifier. If you have a 200 watt amp,,,use a speaker rated a minimum of 200 watts,,,,400 is better.
It will power two 400 watt lamps.
400
1 Joule is 1 Watt-Second. 1 Watt Hour is 3600 Watt-Second or 3600 Joules. 400 Watt-Hours is 1440000 Joules.
400
300
400 is 133% of 300.
400
To convert 400 Watt hours to BTU, you need to multiply by 3.412 to get the energy in BTU. So, 400 Watt hours is equivalent to approximately 1364.8 BTU.
It rounds to 300