Hey Bater!

If you're talking about an ART MPA, then you've got one of the nicest preamps you're likely to find under a thousand dollars. FMR RNP is another good one.

But you want to avoid upper frequency distortion, if I understand you right. Where esses become eshes. That MXLv69 has mixed reviews...but mostly good ones, especially if you replace the tube with something like a NOS Mullard or Telefunken. Not a bad mic at all. But you may still catch some harshness due to the nature of Chinese condenser mic design. Since you've been using a dynamic, you might want to check out the Shure SM7b, an excellent choice for a less than perfect room...that mic, as well as the Electro-Voice RE20, is designed to have a very narrow field to sing in, and very effectively eliminates most everything else. And both mics are very smooth and silky on the top end.

Another mic worth checking out is an Oktava 319, usually found used for $100 or so...these Russian mics are very good at smoothing out the high end, no Chinese hash.

If you do get one of the millions of Chinese manufactured condensers, maybe consider getting one modded by Michael Joly at oktavamod.com. I'm getting a Gauge ECM-87 modified by them, and I fully expect my "pretty good" mic to graduate into Neumannesque splendor.

http://www.soundclick.com/MarkKaufman