anyway, here is the general settings I'd try with any pedal/amp before I do the fine tweaking.
Heavy Metal (Pantera) : crank the bass up , mid controle set to 0 or 1 , the highs are about 4 or 5.
Heavy Metal (Metallica/Megadeth) : same as above with little more mids.
For a Rock sound I'd move down the bass little, crank the mids a little , keep the highs at half.