The 4x4A is a high−performance switcher for unbalanced stereo audio signals. It switches any one of four input signals simultaneously to four identical outputs.- S/N Ratio - 90dB.- Level (Gain) Control.- Size - Compact TOOLS - 3 units can be rack mounted side-by-side in a 1U rack space with the optional RK-3T rack adapter. - compatible with RK-3T 19-inch rack adapter for mounting 3 Kramer TOOLS™ into a 1U rack space.Applications:- Audio production and duplication studios.- Audio field production applications.- Multimedia and Presentation audio switching and distribution.