cancellation??? no. that only occurs when the subs are out of phase. these are inline with one another. the port of course is tuned to the 40hz so @ about 80-100 there is some cancelation as the air from the cone and the air from the port are out of phase but that is to be expected.
well as i said i had the RFD2210'S hoohed up to that same FR amp b4. i spent about $350.00 on the 2210's and about $200.00 for the pi's. double cone space = more sound. half the money = more money for real speakers like my demo vehicle from MTX