Yosoo TDA7498 Class D 2X100W Dual Channel Audio Stereo Digital Amplifier Board High-Power Class D digital amplifier High-Power Class D digital amplifier Operating voltage: 15 ~ 34VDC Efficiency: 90% Recommended Power supply: 24V voltage output current over 5A (power shortage in power is a major dynamic phenomenon will appear when the staccato). Recommended speaker impedance: 8 ohms Best