The purpose is only to make wiring easier. If you have a "bank" of multiple subs you have more terminals to fit all the wire on.Since I don’t fully understand the purpose for two terminals on a mono amp, I have no way of knowing if what he says is true.
Can someone explain?
I'm not sure how you get 2.3 Ohms from a series/parallel of (3) 4 Ohm subs? Perhaps you meant 2.6 Ohms?I was prepared to set all subs at 4 ohms and wire them series/parallel for a final ohm load of 2.3 with all subs getting equal power.
IIRC the switch on those subs aren't EXACTLY 2 or 4 Ohms? There's some amount of play. So I would expect a different final impedance from the series string vs single sub string in that Amazon post. You could measure to verify but that's still a DC nominal measurement. You be the judge but if the subs are sharing air space then I would parallel them all.