Control Range: The 7-band equalizer adjustment range is 12db, composed of TI or TL074 circuit, 60HZ, 150HZ, 400HZ, 1KHZ, 3KHZ, 6.5KHZ, 15KHZ seven frequency bands, the knob is in the middle as the , counterclockwise for attenuation, clockwise for boost. Basic Parameters: 7 band sound equalizer preamplification gain, 4580 classic op amp provides 5 times amplification (14dB); input impedance 20K, output impedance 600 ohms. Compatible with Headphones: sound equalizer ear amplifier part of the NE5532 composed of type 47 headphone driver circuit, easy to drive all types of headphones, adjustable high and low. 3.5mm Interface: 3.5mm input interface supports 4 pole plug, the output connects to the headset with a microphone, which can be used on cell phones for normal voice calls, and another terminal with a group lotus interface is available. Regarding the frequency description, 60HZ is heavy bass, 150HZ is bass, 400HZ is mid-bass, 1KHZ is mid-range, 3KHZ is mid-treble, 6.5KHZ is treble, 15KHZ is super treble, adjust according to personal listening preferences. Power supply: DC5V-12V, interface specification is 5.5x2.1, 5V power supply has a static current of about 390ma, 12V power supply has a static current of about 140ma, and power consumption is about 1.8w. Item Type: 7 Band Sound Equalizer Power Supply: DC5V-12V Interface Specification: 5.5x2.1 Input Impedance: 20K Output Impedance: 600 Ohms Equalization Circuit Control Range: 12dB Equalization Frequency Band: 60HZ,150HZ,400HZ,1KHZ,3KHZ,6.5KHZ,15KHZ Colour:Black Material:Metal Package Contents: 1 x 7 Band Sound Equalizer 1 x USB DC Cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.