Do you have to make seperate enclosures for each sub or can you just make it one big open space on the inside?
As long as you measure the air space right, you can have just a single chamber, but I believe you will get a harder bass with 2 separate chambers…
Will a driver have a lower or higher impedance in different enclosures? (small, large, sealed, ported)
This question is based on the idea that every kind of motor (system that converts electrical energy to mechanical energy) I know of will have lowered resistance under greater load, so I would imagine that if a sub had to drive a greater moving mass (e.g. had a larger port size) it’s impedance at a constant frequency would reduce. Any thoughts?
No, the enclosure affects the pressure wave only.
Any electrical charge generated by the woofer picking up that pressure wave(acting as a microphone) will be relatively negligible.