Specification Beyerdynamic A 2

Frequency response 1 Hz - 100 kHz (-1 dB)
Signal-to-noise ratio >101 dB (unweighted)
T.H.D 0.001% at 170 mW/250 Ω
Input impedance 50 kΩ
Output impedance Headphone output 0 Ω/100 Ω (switchable)
Output power 100 mW / 600 Ω 170 mW / 250 Ω 150 mW / 32 Ω
Channel separation L/R  >89 dB
Maximum gain 18 dB
Power supply 110 - 120 V / 220 - 240 V (switchable), 50/60 Hz
Power consumption (operation) <15 W
Power consumption (standby) <0.45 W