Thanks a lot for your very detailed reply, drew. Obviously, I made a confusion. The other guy that talked about pink noise was using it to find the sweet spot for one mic as well. I thought you were using it that way too, not only for the second. Your technique seems to work pretty well, though. It gives some good beef. I will for sure use in the future, but I have to do something else first... Unfortunately, this doesn't solve my initial problem. I don't understand, no one seems to have the 3k->6k extreme harshness I am struggling with (or not in the same proportions), plus that weird boxy feel. I am obviously doing something wrong, but I would love to discover what.