ZXY AU-100 Dual Channel Audio Ground Loop Isolator Enjoy Cleaner Audio with Less Unwanted Noise The ZXY AU-100 Dual Channel Audio Ground Loop Isolator is designed to help reduce unwanted hum, buzz, and ground loop interference in audio systems. Featuring a passive isolation design and a 600:600 impedance ratio, this audio noise eliminator is an ideal solution for studio recording, live sound reinforcement, and various professional audio applications. Equipped with a Permalloy