TDA7294 is a high-power and high-voltage DMOS high-fidelity power amplifier IC. It is packaged in a single-row dual-row 15-pin package. VS (power supply voltage) ±10---±40V; I. (peak output power) 10A; p. (RMS continuous output power) 70W when VS=±35V 8Ω; 70W when VS=±27V 4Ω. Distortion＜0.006%. The design has the advantages of bipolar signal processing circuit and power MOS. It has the characteristics of high voltage resistance, low noise, low distortion, and the playback sound is very friendly; and has a silent standby function, short-circuit current and overheating protection functions to make its performance more complete. This board is powered by DC and cannot be directly connected to the transformer output. A power supply board must be added.(power supply board NOT included). Installation use note: The working power supply is DC voltage, which cannot be directly connected to the transformer, but must pass through the power supply board. Insulating particles and insulating sheets must be installed between the chip and the heat sink. It is recommended to use a dual 15-28V transformer with a power of not less than 100W! The impedance of the speaker is 8Ω. It is recommended that the output voltage of the transformer be double 24V. When the impedance of the speaker is 4Ω, the output voltage of the transformer is recommended to be less than double 21V, and pay attention to increase the heat dissipation area. During the power-on test, the signal input terminal on the board must be connected to the load and cannot be suspended, otherwise there will be induced noise. The signal line should be shielded as much as possible. If the board is installed in the chassis, be sure to connect the casing of the chassis to the ground wire of the input terminal on the board. If the front stage is added, the input ground of the rear stage does not need to be co