1) the Mic pre’s on this particular mixer on cheaper so the gain stage is diiferent...
2) the EQ on these channels is constantly on - in other words each channel is constantly being pushed thru the EQ even if it is flat lined
3) there is no VLZ (very low impetance) factor on this particular model of mixer. The VLZ pro series are known for their quietness because of this technology, but the CFX series does not have this.... henceforth you get more noise