The ST-SSR1 was designed for absolute silent switching of audio signals. It supports two balanced line-level inputs and one balanced output. Each can be used unbalanced as well. The ST-SSR1 is perfect for switching between two input signals or as a silent On/Off switch for a single channel. Performance is in keeping with the technical standards for which RDL has become known. The user can program the module for either fast or soft switching. The SELECT input feeds the OUTPUT when the TRIG terminal is grounded, otherwise the OUTPUT is fed by the NORMAL input.The control current required at the TRIG terminal is so minimal (< 0.5 mA) that the ST-SSR1 can be controlled from nearly any source from switches to logic circuits. Switch Line Level Sources; Select Between Two Balanced Lines; Silent Audio Switching; Switching Without Hard Relay Contacts; Fast Switching for Audio Muting; Selection by Open-Collector Logic.