Use the power amplifier board as far as possible away from the signal (router) When connected to a 4 ohm speaker, the power supply does not exceed 12V, when connected to an 8M speaker, the power supply does not exceed 24V4, and the supply current is recommended to be more than 2A. The speaker wire should not be too long, that it is suitable within 1 meter Power supply: DC 8V ~ 24V, more than 2A; matching speakers: 4-8 ohm / 30-150W; input voltage must be lower than 26V, otherwise the Bluetooth amplifier board be . If you need a more powerful audio amplifier board, you can buy other audio amplifier boards in our store. Adjustable volume: turn the adjustment button to increase the volume, turn to the left to decrease the volume; the button to play / stop audio; Safety protection: anti-reverse protection, short circuit protection, over temperature protection (note: when the output power exceeds 20W x 2, a radiator is required); Bluetooth: version 5.0; effective transmission distance: 10-15 meters / 32.8-49.2 feet (barrier-free), when the power is on and the connection is successful, a short and clear prompt sound; Mini stable: suitable for every installation situation; better audio performance, very suitable for your home or car system. 1. Parameters: 1. Product name: XY-P15W stereo Bluetooth power amplifier module 2. Model: XY-P15W 3. Channel: dual channel 4. Output power 6.1- Output power 16W x 2 12V 4ohm-12V 4ohm-Output power 8ohm-12V, output power 16mhm colour: black Material: PCB size: 50 x 33mm Package Contents: 3 x XY-P15W Bluetooth power amplifier board 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.