James Boyk, Pianist In Residence at the California Institute of Technology (where he teaches), is a performing musician, recording engineer at his label Performance Recordings, equipment reviewer, and long-time audiophile. In one talk he gave, he described how the timbre and tonality of his piano changes as a long-held notes/chord fades to silence, the relative strengths of the fundamentals and all their overtones changing as the notes fade. When he evaluates equipment, James listens for the ability of the product under test to reproduce that changing timbre he knows is contained in his recordings of he playing his piano. Wow! Last I heard, his monitor and pleasure listening system consisted a pair of the original Quad ESL’s, tube electronics, and a Linn Sondek table.
Most pro musicians are very concerned with the quality and character of the recorded sound of their guitar, voice, violin, piano, etc. Some of THEM are concerned to the point of obsession---Ry Cooder, for instance. To those musicians and singers, true-to-life timbre/tonality trumps all other concerns in recorded and playback sound quality---dynamics, phrasing, pace, etc., though also very important, take a back seat to the actual sound of their instrument and/or voice.