1. Using professional audio VU driver IC, not the TA7318 we used before, this IC contains square root dynamic compression circuit, logarithmic output characteristics, to avoid the small signal pointer does not move, when the signal is large, the pointer hits the bottom The phenomenon. 2. The IC has a mute function. The mute function pin will get a low level at the moment of power-on, which can avoid the phenomenon of the pointer hitting the bottom at the moment of power-on. In order to comply with the boot habit, the pointer will swing with a small swing. 3. The circuit uses 6-12VDC power supply, using IC BA6138, it will be very convenient to use. 4. The double-sided circuit board is used to the firmness of the crimping terminal, so that the pads of the terminal may not be loose after multiple wiring. 5. Each drive board has been tested and adjusted by our professional test stand to the consistency of quality. The design and layout of board are beautiful and reasonable, and there is no interference and self-excitation. Each board has been tested and adjusted by our professional test stand. There is no special requirement. We input 1W/8 ohm (2.83V), and use the P-55 meter to do the load test. The pointer swing is 0DB scale. If you have special requirements, you can send a text message to explain. In addition to adjusting the load potentiometer, the swing adjustment can also be considered from the input voltage divider circuit. The brightness of the backlight can be achieved by adjusting the resistance of R9 and R10. With the electrical parameters of the backlight, it can be easily calculated according to Ohm's law. If you want to help, please text us. Crimp terminal: The crimping terminal we choose has a moderate height. The most important thing is that the crimping is very reasonable, which can firmly compress wires of sizes. In addition, we use a double-sided board, and the pads of the crimping terminals are relatively firm and not easy to loosen. Circuit board size: The installation size of the circuit board, the outer frame is 67.4MM x 56MM, and the installation size of the screw hole: 57MM x 50.5MM. M3 screws are suitable for the screws. Colour:green Material:PC+Metal Package Contents: 1 x Driver board Only the above package content, other products are not included. Note: Light 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.