Features: Onboard PT2314 sound quality processor chip The module supports four sets of stereo input and two-channel output The module supports volume adjustment, treble and bass adjustment, mute and other functions The module supports the I2C bus to realize the programming of all functions Onboard power indicator and filter electrolytic capacitor.The main pins of the chip have basically been led out Product parameters: Power supply voltage: 6V-10V, 9V recommended Instructions for use: Test chip: STC89C52RC Wiring Instructions: P3.6(-)SDA P3.7(-)SCL Instructions: P2.0-Mute P2.1-channel selection (choose one of the four channels) P2.2-Mode selection (VOL/BASS/TREBLE) P2.3-Increase amount P2.4-Reduction note: The products due to different batches of components, but this does not affect use. Material: PCB+components colour: Blue Package Contents: 1 x PT2314 Module 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.