In listening to your system(s)...what is most crucial to your enjoyment?

In growing up around live musicians and instruments, the authenticity of sound, timbre ( Timbre is French in origin, which is apparent in its pronunciation: it is often pronounced \TAM-ber\ and, with a more French-influenced second syllable, \TAM-bruh\. ... And timbre may also be correctly pronounced just like timber as \TIM-ber\) ...a search finds diversity to the definition of timbre.  For me, it ties to "my truth" when I hear non-amplified instrument or group of instruments, voice or voices presented before me.  Changes to my system either get me closer or further from my truth.  Emphasis "my truth" because I've come to believe, like our other senses, it differs among us, leaving "experts" to theirs, some of which seem to "fit" mine.  It's fun when that happens.  Robert E Greene of TAS and Art Dudley of Phile seem to have advised me towards my truth over the years (with bits of disagreement here and there) but, they have steered me well, thanks.  What do you find crucial?