The amount of $6000 is a large budget, which means it has to be value to buy a high-end headphone with this budget. HifiMAN Susvara, is that the answer? You have to answer for yourself. As for me, these are flagship headphones and offer very excellent sound detail and an extended frequency response that fast. These most expensive headphones offer an extremely natural-sounding soundstage. However; one big issue for these high-end planar magnetic headphones, is that you need to have an extremely clean and powerful headphone amp to get the best result. If the budget is not your problem and has remained cash, you can try to S.M.S.L SU-9 MQA Full Decoder Amplifier or Denon PMA-800NE Stereo Integrated Amplifier which was especially great for Susvara. [ .. Read More .. ]