Dynamic Headroom

Al - I like percents or ratios instead of dB. In case of 500W vs. 30W ratio of perceived loudness is:

R = (500/30)^(1/3.5)= 2.23 where "^" means "to power"

Grimace,

Before the post turned into a congressional assembly, I think Al's initial post is a legitimate answer.

Cyclonicman - Thank you for you valuable summary.

Thanks for all the comments. Feel free to battle it out. Interesting conversation

Kijanki...The 47 volts you cite is DC. Allowing for a 3 volt drop through the output transistors this suggests that the amp can swing +/- 44 volts. But that 44 volts is the peak of the signal. For a sine wave signal this would allow 228 watts RMS.

Almarg...We agree. My point is that an amp which is current-limited for high voltage output is a logical design for signals that have huge peak-to-average ratios (like music). Having current to spare is no help if you can't swing the voltage. We use amps with huge power specs because that assures the voltage swing. Having that swing continuously is not really necessary.