what does dynamic power rating mean? I see the orion 2500d that I just bought has a dynamic power rating of 5000 but not exactley sure what that means.
There aren't many companies that rate it accurately, and even if they do - it's such an inconsistency between brands you can't really use it to compare anything. IMO - ignore it.
in short, that rating is a measure of the peak output capability of the power supply in the amplifier, letting you know what it's peak output will be before it clips at the peak of a sine wave.
If you want the continuous output stick with RMS and CEA2006 ratings.