Like Jason says I’ve always preferred to run my M80s with a lower than 80Hz crossover usually 40-50Hz depending on the room. I would worry about your 3808 not being able to power them unless you are listening above 105db or so depending on the distance to your speakers in which case you wont be enjoying your system for very much longer due to hearing loss.
You could also try repositioning your subwoofer which might help some. Though if your room is like mine I have room modes which cause a huge peak around 20Hz and similar dip around 40-50Hz so the mid bass thump gets sucked out of my EP500 and overpowered by the low bass rumble. Multiple subs may help your situation but didn’t mine so I had to resort to EQ. OTOH running your M80s with a lower crossover is less expensive and you already know it works in your room.
