Just got these they are INCREDIBLE. Integrated AMP and DAC on the headphones themselves. Have to place the transmitter high because it's infrared (which is lossless, unlike Bluetooth, Kleer, but has static problems sometimes).
They had a European Plug, so I had to buy a step-down transformer 220V-120V.
They sound just like the HD580/600, but better because of the DAC.
Anyone else have experience with these? Just wondering who else owns these hard-to-find 'phones?