ZK-502D bluetooth 5.0 Audio Power Amplifier Module Board 50W*2 Dual-channel Stereo Aluminum Alloy Shell

Feature
Product name:50w * 2 Bluetooth 5.0 audio power amplifier module
Product model:ZK-502D
Bluetooth version:5.0 (unobstructed, 15 meters)
Signal to noise ratio:> 95dB
Input method:USB + AUX + BLUETOOTH
Number of channels:left and right dual channels (stereo)
Amplifier chip:TPA116D2 (with AM interference suppression function)
Adaptable power supply:DC9-24V / 5A or more (the higher the voltage, the greater the output power)
Adapter speaker:20 ~ 200W, 2 ~ 8┯
Output power:20W * 2 @ 12V, 8┯ / 35W * 2 @ 12V, 4┯ / 35W * 2 @ 19V, 8┯ / 60W * 2 @ 19V, 4┯ / 50W * 2 @ 24V, 8┯ / 90W * 2 @ 24V, 4┯
Protection mechanism:overvoltage, undervoltage, overheat, DC detection, short circuit protection
Product size:100mm * 77mm * 22mm
Product weight:185g (including packaging)
Prompt
Only when the audio input is sufficient and the power supply voltage / current is sufficient, will there be enough output power!
The higher the power supply voltage, the greater the output power, the smaller the speaker impedance, the greater the output power!
Please make sure that the power of the adapted power supply is greater than the actual working power of the amplifier!
Package includes
1 x Audio Power Amplifier Board kit (The power adapter is not includes)
Question & Answer
Q1. How to choose the power supply
A:The power supply of the board is very important. The higher the voltage, the higher the current, and the greater the output power. If you only have 12V 1A, you can use a 3-4 inch speaker. If you are above 19V 5A, there is no problem with 8-10 inch speaker, the power supply must be highly valued. If the voltage is too low, the sound will be easily distorted after the sound is amplified. If the current is too small, the speaker will pull down the voltage, and will not work properly or the sound quality will deteriorate.
It is recommended to use 18V/19V/24V power supply, the current is more than 5A. If you only have a 9V/12V or 1A, 2A power supply, it can also be used but the power is small. Note that the maximum volume during use may be distorted and affect the sound quality.
Q2. How to choose speakers
A:The commonly used speakers are generally 4-8 ohms, and the positive and negative polarities can be distinguished. The effect is the same. 2 ohm speakers can also be used. If your speaker power is small, it may be usable between 20W-50W. The supply voltage is lower to prevent the speaker from being burned after the sound is amplified. For example, choose a power supply below 15V. If you are a 100W-200W speaker, you don’t need to worry about the problem of speaker burnout， you can choose a 12-24V power supply, the higher the voltage, the greater the output sound or power. Speaker power should not exceed 200W, otherwise it will affect the sound quality.
Q3. How to select the audio input mode
A:This audio power amplifier module follows the principle of hardware connection priority. USB connection is successful in USB mode, AUX plug-in is in AUX mode. If USB is not connected and AUX is not plugged in, it is Bluetooth mode, Bluetooth mode supports automatic connection back. There is a mode prompt tone when the mode is switched. When selecting the USB audio input mode, it should be noted that USB can be directly connected to devices such as computers with USB audio output, without installing a driver. USB input is lossless input, good sound quality, no interference, no noise.
Q4. The sound is okay. When the sound becomes louder, does the sound appear muddy
A:The sound is distorted. Please change the power supply of the adapter with higher voltage level.
Q5. It’s okay when the sound is small, but when the sound becomes louder, the sound freezes
A:There may be two reasons:1. Insufficient input power, intermittent power-off protection of the power supply itself, please replace with a larger power supply; 2. Too much power, the power amplifier board heats up seriously, and thermal protection occurs. Should reduce the use of power or strengthen heat dissipation.