The 2 channel Line Level Shifter is designed to allow you to use equipment with different line level requirements at their correct gain settings. This will reduce noise and enable you to use any piece of equipment. Connect -10 gear to +4 gear with both units set to optimum gain levels. Balanced or unbalanced lines may be used at either level. The TRS smart jacks do all of the rewiring for you. For unbalanced signals just use standard 1/4" two conductor connectors. For balanced signals use 1/4" three conductor (TRS) connectors. No power required for operation, just plug in and play.