Just to add to what everyone else has said, yes upgrading to M60's would help with the lack of midbass the M2's do not have. I would also try the crossover at the max 100hz your sub is capable of. I think this may help but I also feel that you will still not achieve the same output in the mid bass you would have with the M60s plus sub.


Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70