The multi-mode Horizon STL-1 Stereo Line Direct Box functions as 2 separate direct boxes in stereo mode. In mono mode 2 high-impedance, unbalanced input signals can be combined into one low-impedance, balanced output mono channel to conserve channels in a snake. Also in mono mode, 2 high-impedance unbalanced signals can be combined into one low-impedance balanced signal, isolated and split into 2 separate mono output signals. The Horizon STL-1 comes with 2 shunts on the input jacks to eliminate feedback noise.