Feature:1. Sound adjustment: support high/medium/bass EQ adjustment, enhance +15dB and attenuation -15dB, support left and right channel balance adjustment, suitable for tone adjustment.2. Three sets of stereo mixed input :3.5mm+6.5mm+RCA.3. Provides three sets of stereo output simultaneously:RCA+RCA+3.5mm.4. Independent Toner Audio Control: With independent audio source channel high/middle/bass control. Attenuations -15dB and +15dB gain, the sound adjustment design allows you to adjust the audio independently and control the output volume independently.5. Simple installation: input and output plug and play easy installation, enjoy music instantly.6. USB 5V power supply, suitable for outdoor mobile power use, with wider application range.7. Compact and desktop design, and can be compatible with any devices.Specification:Features:Sound adjustment: support high/medium/bass EQ adjustment, enhance +15dB and attenuation -15dB, support left and right channel balance adjustment, suitable for tone adjustment. Three sets of stereo mixed input :3.5mm+6.5mm+RCA.Provides three sets of stereo output simultaneously:RCA+RCA+3.5mm.Independent Toner Audio Control: With independent audio source channel high/middle/bass control. Attenuations -15dB and +15dB gain, the sound adjustment design allows you to adjust the audio independently and control the output volume independently.Simple installation: input and output plug and play easy installation, enjoy music instantly.USB 5V power supply, suitable for outdoor mobile power use, with wider application range.Compact and desktop design, and can be compatible with any devices.Specifications:Material: MetalInput channel: 3-way stereo input 3.5mm+6.5mm+RCA interfaceOutput channel :3.5mm/RCA interfaceInput impedance :100K OhmOutput gain: high, medium and low -15dB and +15dBFrequency response: 20Hz-20KHzSignal to noise ratio: more than 107dBTotal Harmonic Distortion: less than 0.08%Intermodulation distortion: less than 0.01%Charging Connection: USB 5VItem Size: 130 * 77 * 38mm / 5.11 * 3.03 * 1.49inItem Weight: 380g / 13.4ozPackage Weight: 530g / 18.69ozPackage Size: 20 * 18.5 * 5.5cm / 7.87 * 7.28 * 2.16inPacking List:1 * Stereo Preamplifier1 * USB power cordPackage List:1 * Stereo Preamplifier1 * USB power cord