1. The first stage is the RFI filter DC circuit. Using two 50A bridge rectifiers and four 35V 2200μF capacitors, it filters the DC component from the AC power supply to reduce buzzing caused by transformer saturation or increased static current. 2. Differential mode filtering uses two differential inductors to suppress medium and high-frequency interference from the AC power supply. 3. First-level common mode filtering is achieved using an X2 capacitor and a common mode inductor, forming a primary common mode filter. 4. Second-level common mode filtering provides enhanced performance due to the two-stage design, effectively suppressing fast transient burst pulses with repetition rates in the kilohertz range. 5. This module is designed to be used with decoders or power amplifiers to filter DC components, reduce transformer hum, suppress high-frequency noise, and purify the power supply, resulting in improved amplifier sound quality, increased resolution, and a quieter background. Name: Audio Power Amplifier Filter Input Voltage: AC 110V–250V (Max 250V) Output Voltage: AC 110V–250V Filter Technology: EMI Wi-Fi: No Grounding: Standard Grounding Type: Audio Power Amplifier Filter Working Current: 20A Color: Black Material: ABS Size: Board Size: 108mm x 50mm Package Contents: 1 x Filter Note: Light reflection and display differences may cause slight variations in color between the image and actual item. Measurement error allowed within +/- 1–3cm.