The HD 598s have a rating of 50 ohm. It has USB outlets which is very appreciated so I can use the main outlet for my laptop and the USB ports for my phone and iPad. Maybe it will go away eventually. Great comfort for my lower back pain. El material y tamaño de los protectores de las orejas son adecuados, grandes y muy suaves. absolutely perfect for my wedding dress its hard to pack at first but I figured it out. Needed to physically cut open the case to have it removed, it left scratches on my AirPods case as well. I have to give an honest review, and as I feel 3 months is appalling for such expensive boots, Ive altered my rating accordingly. Too bad they dont stay in your ears.