Many male voices go well below that 300hz, I am finding the 200hz on the VP160 works very well for me, but play away, no harm in that. I have always wanted to build my own speakers but never allow myself enough time to do it, so I will live vicariously through your project.

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