I got an Atomic 5000.1 as a trade a little over a week ago. I didn't have time to do much today with it being the 4th and all, but I did a test at one frequency on my system - DD 9515 Dual 1 wired to 0.5 ohm, AT 5000.1, Kinetic 2400 in the back, Optima g34/78 in the front, stock alternator. Well, here are the quick results, take them for what you will:
Frequency - 40 hz
AC Voltage - 70.9
AC Current - 56.4
Power - 3998.8 watts
Impedance - 1.26 ohm
Voltage drop - 14.4 to 11.7
So, the amp put out 4kw on 11.7 volts at 1.26 ohm. I was happy. More tomorrow.
EDIT: The rest of the results
Did some more testing using some other frequencies, here are the results. I can definitely say that I am really impressed with the results. However, I am sure there is quite a bit of uncertainty, and these may be inflated results, but the tests were done the same way as all other clamp tests.
Quite frankly the results seem too good to be true, so I don't know what happened. But those are the numbers the meters showed.