AKG K701 Open-Back Reference Class Stereo HeadphonesThe AKG K 701 stereo headphones offer audiophile frequency reproduction and comfort, with a vastly extended high frequency ranging to nearly 40kHz. The patented Varimotion dual layer diaphragm design, and flat wire voice coil technology, offer high sensitivity, durability and clarity, with improved definition of both sonic detail and stereo imaging. Circumaural, open back stereo reference headphones HF reproduction to almost 40kHz for increased top