Specification: Product model: YS-AP50L Power supply voltage: DC: 5-24V (the higher the voltage, the greater the output power) Bluetooth-compatible version: 5.1 Transmission distance: 15 meters (without obstruction) Number of channels: left and right dual channels (stereo) Adapted speaker: 30W~200W 4 Ω 8 Ω 16 Ω Protection mechanism: power reverse protection, short circuit protection, self recovery overheating protection Unique feature: supports YS Audio APP control Product size: 52x52x22mm/2.04x2.04x0.86inch Product weight: 77g Note: The output power of the power supply should be greater than the output power of the amplifier, otherwise it will affect the sound quality 12V-8 Ω/15W+15W, 4 Ω/20W+20W 15V-8 Ω/18W+18W, 4 Ω/greater than 30W+30W 19V-8 Ω/32W+32W, 4 Ω/greater than 45W+45W 24V-8 Ω/40W+40W, 4 Ω/greater than 50W+50W Precautions for Use: 1. Use the power amplifier board as far as possible away from the WIFI signal (router) 2. The recommended power supply voltage is 5~24V DC. If it exceeds 26V, the chip may burn out. 3. The recommended power supply current is 2A or above. 4. The horn cable should not be too long, ensuring that it is suitable within 1 meter 5. Pay attention to static electricity protection. Before touching the power amplifier board, release the static electricity on your hands to avoid static electricity damaging the chip. Bluetooth chips are sensitive to static electricity. 6. Suggest adapting the speaker with a rated power of 40W or above to avoid overheating and burning of the speaker Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement. Included: 1 x amplifier board kit with casing and tools Smartphone App Control: Compatible with both Android and for iOS systems, the app allows you to control the playback mode, volume, equalizer, track selection, and more. You can also modify the digital power audio amplifier board's name and set a connection password (YS Audio-APP). The Bluetooth-compatible function can connect to smartphones, tablets, laptops, AUX devices such as MP3 players, and more. It can be connected to both passive and active speakers. USB Audio Card Function: This power amplifier board can output high-quality signals to speakers via USB, delivering better sound quality than a computer's built-in sound card. Connect the Bluetooth-compatible board to your computer using a data cable, switch to "audio card" mode on the APP, and you're ready to play music through your computer's media player. USB Playback Support: This stereo AMP amplificador supports playback from a USB drive. Simply plug in the USB drive, switch to "USB" mode on the APP, and you're ready to play. Note that the USB interface is a Type-C port. Bluetooth-compatible 5.1 Amplifier: With a transmission distance of up to 15 meters (unobstructed), this audio power amplifier supports 2.0-channel stereo output, with 50W*2 (left and right channel) pure HIFI audiophile sound quality. The high frequencies are crisp and clear, the middle-range is gentle and delicate, and the bass is powerful and impactful. CS8673E Chip: The CS8673E chip within this digital power audio amplifier board features a high-efficiency Class D audio power amplification circuit with low distortion and noise prevention. It provides clear and powerful sound quality, and comes with overcurrent, short-circuit, and overheat protection to prevent damage to the chip under abnormal working conditions.