Hifi Headset Amplifier Companion Walkman Portable Adjustable Amp 3.5mm Aux Port

Features: This HiFi Headphone Amplifier supports impedance 16-150??, Delicate, Compact and Portable, Which Make it Convenient to Carry, Can Output Remarkable Sound without Distortion. 3.5mm AUX Input and Output High Quality Audio, Suitable for your Mobile Phone MP3 MP4 Laptop PC Noise Reduction Function, and Distortion with Enhanced Dynamics, Perfect Pure Stereo Effect, HD Voice Music Sound Quality Optimization Aluminum Matte Surface, Fashion and Compact Design Not only suit for music enthusiast, also could be a ideal gift for those who has trouble hearing. Specifications: Input/Output Port: 3.5mm Audio Port Distortion: 0.004% SNR:??????? 20dB Load impedance: 16-150?? Max. Power output: 250mW in Impedance 16?? Amp Internal Voltage:?? 4V Charging voltage: DC 5V Frequency response: 20Hz-20kHz(?? 3dB) Lithium-Battery capacity: 1000mAh Amp Using Time: about 6 Hours Dimension: 9.5*6.2*1.5CM Net weight: 160G Troubleshooting Q: Why there is an buzzing/hissing sound? A: Please don't use it while charging because current disturbance will occur when in charging. That's why there is noise. When fully charged, please disconnect the power supply, and then use the headphone amplifier. Q: This amp doesn't amp high enough for my bigger headphones, and why? A: This headphone amp supports headphones with 16-150 ohm impedance. Please check the impedance of your headphone.