ZK-HT21 15-36V 2.1 Channel Stereo Bluetooth 5.0 Digital High Power Subwoofer Amplifier Board 160Wx2+220W TDA7498E AUX USB bass

Description: 1. How to select power supply? power supply of the board matching is very important. The ripple of the selected power supply must be small. The power supply with large ripple will cause the noise at the bottom of the power amplifier board to increase and there will be current sound. The higher the voltage, the higher the current, and the more sufficient the output power. If you only have 12V 1a, you can bring a 3-4 inch speaker. If you are above 19v 5a, with 8-10 inch no problem, power must be attached great importance. If the voltage is too low, the sound amplification is easy to cause sound distortion. If the current is too small to bring up, the horn will pull down the voltage, work abnormally or the sound quality becomes poor. It is recommended to use 18v19v2v power supply with current above 5A. If you only have 9v12v or 1A 2A power supply, you can also use it, but the power is small. If the volume is close to the maximum, it may cause distortion and affect the sound quality. 2. How to choose the horn? On the type of horn: commonly used horn is generally 4-8 ohm, can be used. The left and right channel speakers need to be connected with full frequency speakers or medium and high frequency speakers, and the power is between 20W and 100W. Subwoofer speakers can not be connected to speakers, need to be connected with subwoofer speakers, power between 20-100. The subwoofer horn should dive at least 50 Hz. If your speaker power is small, such as between 20w-50w, it can also be used. The power supply voltage needs to be smaller to prevent burning the speaker after loud. For example, choose a power supply below 15V. If you are a 50W - 100W speaker, you don't have to worry about the burning problem of the speaker. You can choose a 12 - 24 V power supply. The higher the voltage you choose, the more sound or power you can output. The power of the loudspeaker is not easy to exceed 100W, otherwise the sound quality will be affected. 3. Introduction of audio input mode This audio amplifier module has two audio input modes: one is Bluetooth input, the other is aux input, and Bluetooth mode has priority. Bluetooth can be connected in either mode. As long as the Bluetooth connection is successful, it is Bluetooth mode, and the Bluetooth mode supports automatic connection back. When Bluetooth is not connected, aux is inserted in aux mode. It should be noted that when using aux mode, it is necessary to confirm that the Bluetooth connection of this module has been disconnected. 4. How to adjust the main volume? The main volume knob is used to adjust the main volume. The right main volume increases and the left main volume decreases. The main volume affects both the left and right channels and the volume of the subwoofer.