Fosi Audio N2 Headphone Amplifier 3.5MM Portable Amp Gain & Bass Switch Audio Hi-Fi Earphone Headset Powered Dual-Output with Lithium Battery for iPhone, iPod, iPad, MP3 and Computers
Brand: Fosi Audio

Audio input: 3.5mm headphone port Headphone output: 3.5mm headphone port Charging port: Type-C Volume adjustment mode: High precision volume knob Power supply: DC 5V 1A Internal voltage：±9.5V Op amp: OPA1642 Current amp: 1W triode to tube Battery capacity: 2200mAH Battery Life: about 12h Magnification (Av): GAIN=L:3 GAIN=H:6.8 Low-frequency gain（BASS=ON）: +6dB Frequency response: 10Hz-25KHz SNR: ＞100dB THD+N: 0.005% Headphone output impedance: 16ohm-600ohm Headphone output power: 16ohm/330mW 32ohm/320mW 64ohm/298mW 300ohm/100mW Dimensions: 4.17 x 2.64 x 0.55 inches (106x67x14mm) Product weight: 126g

Simple compact design but practical and powerful. All-aluminum silver body has been carefully designed and CNC processed to make it compact and classic.
High precision volume knob makes this headphone amplifier easy to use. Features a switch for adjusting gain as well as another switch to fine-tune bass levels. Meets the needs of bass lovers.
Low-pass filter duties on the line-output are handled by the OPA1642 chip. High fidelity stereo headphone amplifier and 3.5mm input/output jack, stream Hi-Fi music to your stereo system.
High-performance headphone drive and circuit protection. 2200mAH internal battery powers for up to 12 hours of use. Load Impedance: 16-600Ω. Output remarkable sound without distortion.
What you Get: N2 Headphone amplifier x1, User Manual x1, Type-C power cable x1, 3.5mm to 3.5mm cable x1, an 18-month worry-free warranty and friendly customer service.