The MP507 is a single channel preamp that utilizes a single 12ax7 vacuum tube. It has a MU-Metal audio transformer to decrease noise and enhance the sound quality of the XLR Input. The design of the MP507 utilizes a high speed self regulated switching power supply to generate 230V of clean usable plate voltage for the 12ax7 vacuum tube. The result is a clean and powerful sounding tube preamp.FeaturesReal 230V tube plate voltageInternal high speed self regulating switching power supplyMU metal shielded Input audio transformer48V of clean, quiet phantom power