the mix pre scale is ppm one , so if you want to match it to dbfs scale
the 0 dbu tone on your mixer = -20 dbfs
adjust the gain that the piks would hit the +12.+14 dbu , place the mixer limiter on the top ( +18 dbu) to prevent your recording device overload .
THE MIX PRE AUTOMATICALLY attenuate the signal when you use phantom power for 10 db ,if it not enouth put in line pads befor the inputs .