I have a opportunity for one of these units.Does anyone know anything about it. Whay year made? Any Good? I know it is a tube receiver. It appears to be in good condition. Powers up thats all I know. Also would I need a additional amp to go with this? I have a opportunity for a Kenwood Stereo Integrated Amplifier MODEL KA-3700. It appears to be in good condition. It powers on also.