It's the retroflex version of "Zang", where the "z" is sort of like a "t" followed by an "s" sound. "Retroflex" means that the tongue bends a little bit backwar

It's the retroflex version of "Zang", where the "z" is sort of like a "t" followed by an "s" sound. "Retroflex" means that the tongue bends a little bit backwards and therefore touches the palate a little bit farther back. Don't sweat it too much, for most people the whole series of s/sh, z/zh, c/ch, and x/j/q are hard to consistently get right unless they are corrected by a teacher. Also, since romanized Chinese names usually lack tone marks, some ambiguity regarding the correct pronunciation remains.