Hello again,
I think I may have found the answer in Amazon's comments:
Can it charge one device at 9v and another at 5v at the same time?
Answer:
Good question! The manual says nothing about "parallel charging" as you specify, but the FAQ from the Anker web site may provide the answer.
"Q9. Can the 2nd Gen Astro Pro2 20000mAh external battery charge multiple devices simultaneously?
Yes, it can charge four devices simultaneously. But please note that when using 4 output ports simultaneously, the total output current must not exceed 4A.
Actually, I want to charge two devices at 12v, the Tascam DR60D Mkii/Sennheiser MKE 600 combo plus BMPCC, but I don't know if they will exceed that total output of 4A or whether it would be dangerous for any of those two devices if I exceeded it.
What do you guys think (or know)?