Hi guys.. I wanna upgrade from a Sony v6 studio monitor headphones. The sonys serve me well for playing software pianos using my digital piano + computer , but the sibilance issues and exaggerated heights are getting to me. Currently trying to "burn them in" hoping that it would tame them somewhat. I don't enjoy music with it and to me they don't appear to be neutral headphones. (At least to my ears, everyone is different with varying anatomy) I was just wondering the differences between the athm50x and ath m40x? Will the extra 4000hz in the spectrum make that big of a difference? I've read that the older m50s are much less fatiguing to the ear when compared to the sony v6 Everyone's anatomy is different and I figured I'm just extra sensitive to sibilance and the upper range in general. Has anyone had the opportunity to compare these two headphones? Any input would be appreciated. Thanks in advance. Cheers.