ART DTI Dual Transformer/Isolator Passive Audio Interface

ART DTI Dual Transformer Isolator Hum Eliminator

Pyle Compact Mini Hum Eliminator Box - 2 Channel Passive Ground Loop Isolator, Noise Filter,AC Buzz Destroyer, Hum Killer w/ 1/4" TRS Phone,XLR Input/Output, Uses 1:1 Isolation Transformer