Kramer Electronics 901 901 is a high performance integrated personal stereo amplifier for unbalanced stereo signals. It accepts a stereo audio signal and delivers a speaker output of 2 watts RMS power per channel into a 4 ohm load. S/N Ratio - 74dB. Inputs - Line or microphone (condenser or dynamic selectable). Outputs - 3.5mm for headphones and terminal block connectors for speakers. Control - Volume, bass, treble, and balance Compact Kramer TOOLS - 3 units can be rack mounted side-by-side in a 1U rack space with the optional RK-3T rack.