I have song song where there are 6 people on the track. 5 of them are on a MXL 2001 + a ART Tube OPL preamp with a very close promimity(prox 3 inches. The last vocal is using a MXL 2001 + a Studio Projects VTB1 preamp (prox 6 inches. The new vocal sounds way cleaner. What would be the best way to make the old vocals or new vocal sound like they match?