We have a an old powered desk which we use for our PA and we want to run some passive wedges as monitors. Trouble is the desk we use has 6 ohm outputs which is really odd and unusual ohmage. Can you run 8 ohm speakers from this desk safely? This is the safer direction to go right with the speaker having a higher ohmage than the desk? Or do you go lower ohmage speaker say 4 ohms? But this may draw more power from the desk and make it overheat right?