The KZ ZSN Pro is only my third foray into KZ IEM’s, the first being several years ago with the purchase of first generation KZ ED9’s in 2015. My second Chi-Fi experiment was with the acquisition of a pair of second generation CCA-CA4 in-ears in April 2019. Most recently, I took delivery of the subject of this review, the KZ ZSN Pro, in May 2019. My purpose, then, in writing this review is to compare the sound characteristics and qualities of these three "KZ cousins". First, I will say that all three of these IEM’s represent excellent values in the...