Musical Fidelity - V90-BHA Balanced Headphone Amp High quality fully-balanced headphone amplifier with XLR and RCA inputs & both 1/4" and balanced outputs Power: 0.75wpc into 32Ohms Ouput Impedance: 22 Ohms (Suitable for 10-600 Ohm headphones) THD(+ noise): &lt;0.005% typical (20Hz to 20kHz) Frequency Response: +0, 3dB, &lt;10Hz to 37 kHz