I like the image of the "Third order descriptor". @GoodEnoughGear or @Garns can you tell why are you saying : I feel that it is true but I cannot put words on it. For me ringing shows you that the headphones has issue to release some energy at some frequencies. But I do not see it as a REAL big deal. Behind that here is my problem : the description given here : is the one of a very good headphones. I think it will lead to good timbre too, but just because if you respect those criteria you have a good headphones. I would like to narrow down those criteria just in term of timbre. Or at least, justifying (just giving some hint) all those points.