Shure Microflex MX300 Series microphones are surface-mounted electret condenser microphones designed primarily for mounting on conference tables,stage floors, and lecterns. Their high sensitivity and wide frequency range make them especially suitable for picking up speech and vocals in sound reinforcement and recording applications.Interchangeable cartridges provide the installer with greater flexibility and make it possible to easily reconfigure microphone coverage as the need arises. The MX393/0 model includes aninternal preamplifier.MX300 Series microphones take advantage of the principle that, at a barrier or boundary, the sound pressure level doubles. When placed near a sufficiently large boundary surface, the microphone has 6 dB higher sensitivity and approximately 3 dB greater direct-to-reverberant sound ratio.Features:The MX393/0 features programmable logic input and output. Additionally it provides the following benefits:Flat frequency response across the vocal range for uncolored soundInterchangeable cartridges that provide a choice of polar pattern for each applicationSleek, low-profile design for surface mountingProgrammable mute buttonLED on/off indicatorLogic input/output for remote control or use with automatic mixersRF filtering12 foot detachable cable with XLR output connectorSpecifications: Frequency Response: OmnidirectionalImpedance: EIA Rated at 150 ohms (180 ohms actual)Output Level: -6dBV (0.5V)Phantom power required?: 11-52 Vdc phantom, 2.0 mA current consumptionWeight: 172 g (0.38 lbs)