I'm going to switch out my 4 VFL 8's to 4 VFL 10's in the same box. How much will my peak frequency change? My peak frequency is 31 hz. right now with the 8's. I will also be changing amps. I'm going to take out the 3,500 watt smp and put in a 5K amp. My box is 3.9 cubes net tuned to 33 hz. That will be tight for 4 tens.