Hi I spent sometime at the local Sonystyle demoing these and thought I'd share my n00b impression.   I'll start off with the conclusion for those who don't want to read the full review. "These are great in-ear-monitor (IEM) with a VERY strong bass presents, with clear and fine detailed mids and treble (highs)!" The XBA 4 means there are 4 balanced - armature drivers each responsible or the different frequency of music (high, mids, low, ultra low). These are supposed to be compete with well established multi-driver IEMs like Shure SE535(3...