I made a mistake in my calculations. I just updated it. Basically instead of a 9% difference it is a 18% difference in resistance.
The more resistance, the more power you need to get the same volume output. Hence why the one is quieter.
Yes, having 16 on both sides would balance it out a lot better. If you are running 30-40ft, 16 gauge should be fine. Longer, and you should go to a lower number.
EDIT: I can explain more later, but I need to go to bed.








