AC voltage in the range closest to 18.9 volts (I think 200 is the lowest on mine). I personally use a either a 0 or -5 db tone nearest the frequency I'm trying to set. I like 60 for subs, 1000 for mids, and 6k for tweeters.Gotcha. Any idea what setting to use on the MM? The pic I posted was the highest positive number I could find.