About MDrumLeveler :
No drummer’s performance is perfect, each hit has a different velocity, and difference in levels are even exaggerated by the recording equipment. But there is a very high standard for perfectness in performances for most modern styles.
Vocalists regularly use automatic tuner, drummers have MDrumLeveler now. It can even out drum hit levels, so the performance will just sound perfect even if it, well, is not.