JDSLABS C5 Headphone Amplifier Black A high-performance portable headphone amplifier featuring digital volume control, bass boost, dual gain, and up to 14 hour battery run time. Dual Gain: 2.3x or 6.5x, MOSFET controlled Bass Boost: +6.5dB @ 80 Hz Frequency Response	: +/- 0.02 dB THD+N (20-20kHz, 150 ): 0.0009% Noise: -105 dBu Crosstalk @ 150 : -67 dBDigital Stepped Attenuation (63 steps + mute) Ultra Low Noise +/-7V rails, NO power degredation 3.5mm Input and Output Jacks Output impedance: 2.2  Volume Potentiometer Taper: 3B Inter-channel Phase @ 1kHz: +/- 0.01 Channel Balance: +/- 0.55 dB, all volume positions Max Output @ 150: 3.337 VRMS Max Output @ 600: 4.146 VRMS Power Supply: 14.0 Vpp Battery:Lithium 11-14 hours for charging 5 hours( 80% 2hours) 3.7V Li-Ion Battery(charge through mini USB20 Minute Low Battery Indication Size (excluding switches) 99.5 x 61.5 x 14.0 mm (LxWxH)Weight: 119g Accessories: USB cable/Rubber Bumper Feet Instructions Sheet