Audio Technica CP8201 Microphone Impedance Matching Transformer, XLR F to 1/4" M Adapter- Low impedence to High Impedence Matching Transformer- Allows use of LoZ mic w/ HiZ System The Audio-Technica CP8201 Microphone Impedance Matching Transformer is designed to connect a low-impedance microphone to a high-impedance electronic input. The high-quality transformer solves the problem of excessive high-frequency loss and hum pickup.