Features: Front staged stereoed Amplifiers: Provides preamplification function, enhances sound signal, and improves sound quality. Highly/medium/low frequency adjustment: supports highly, medium, and low frequency adjustment, and users can adjust sound effect according to your preference. Supports 3 mixer: With the function of supporting 3 mixer, meet the needs of multiple channel sound input. USB5V power: Designing with USB DC5V power, easy to connect and suitable for various USB devices. Multifunctional adjustment: Supports sound effects adjustment, achieve detailed control and providing quality auditory enjoyment. Specifications: Color: Black Size: about 130x77x38mm/5.12x3.03x1.5inch Input impedance: 100KOhm Signal gain:+20dBV Output impedance: 47Ohm Signal to noise ratio:>107dB Frequency response: 20Hz -20KHz Intermodulation distortion:<0.01% Output channel: Two set of outputs, one before and one after each Power: USB5V, direct insertion and use Package Includes: 1x Sound Mixer note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.