Power Output Impedance Automated test

I ran the Power Output Impedance automated test on a power amp and am not sure of what to make of the result- I could not find any wiki on that test…

Hi @Var, what hardware and software are you running? Is it possible you flipped your specified load impedances?

QA402 and 1.161. THe test prompts you to connect to either the 8 or 4ohm load so I am pretty sure I did it correctly, but can certainly try it again…thanks for getting back with me

OK, thanks. When you watch the measurement happen, set the frequency range to something narrow and make sure you have the peak DBV display active. The first test will run (with 8 ohms, for example). And when it’s finished, note the peak amplitude at the last frequency point. And then the second test will run. When it’s done, note the peak amplitude at the last frequency point.

With 4 ohms, the amplitude has to be less. And that will yield a positive output impedance. But if the amplitude with 4 ohms is MORE than the amplitude with 8 ohms, then that will yield a negative output impedance.

I tried it again, this time making sure I was on Peak DBV (was on dBR) and got better results:

That looks more reasonable and now I can calculate the damping factor (for what that is worth) !!

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Just a Wish List thought, but it would nice if the damping factor wasplotted on the right side. I assume that it would be just for an 8ohm load…