Without going into detail, here are my clues so far, in no particular order: I'll leave a lot of sources aside for now. Yes, the IER-Z1R is the bomb, the pinnacle of my quest for sonic excellence. So far, they are best used for special occasions. A bottle of wine is required. I still have UE10 Pro, UE11 Pro, W80 and MDR-Z1R. My current sources are Sony TH-ZH1ES and FiiO Q5 (upgraded to Q5S soon). The W80 are general purpose headphones, while the IER-Z1R is for critical listening.
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