im trying to set up my 605 manual as ive just got a sound meter .ive done the distance of the speakers witch was pretty good anyway just the fronts a bit out.but when im runing the sound check what volume should i put it on to get the 75 db from each speaker.and is 6 ohm correct for mezzo alumni, combo.any other tips would be great ive got about an hour to do this before the kids get back.