Neumann NDH 20, Studio Headphones, Frequency range: 5 Hz - 30 kHz, Dynamic 38 mm drivers with neodymium magnets, Impedance: 150 Ohm, Nominal load capacity: 200 mW, Sensitivity (1 kHz, 1 Vrms): 114 dB, Total harmonic distortion (1 kHz, 100 dB SPL):