Shure SM81 Condenser Instrument MicrophoneCardioid condenser instrument microphone offers a wide frequency response and low self noise. Features include flat response curve, low noise and high output clipping level, low distortion over a range of load impedances, and low RF susceptibility. The SM81 is ruggedly constructed. It operates on phantom power and performs over a wide range of temperatures and humidity conditions. It is furnished with a swivel adapter, attenuator switch lock, foam