Shure

collapse expand iconDescription

This Shure Microflex MX391 is a small, low-profile surface mounted electret omnidirectional boundary microphone designed for mounting on conference tables, stage floors, and podiums. The MX391/O mic features high sensitivity and a wide frequency range make them especially suitable for picking up speech and vocals in sound reinforcement and recording applications. The MX391/O has an omnidirectional pickup pattern making it highly suitable for recording or remote monitoring applications.

Microflex Boundary microphones are the high-quality solution for a range of applications, such as altars, boardrooms and distance learning centers. Every Microflex plate microphone features a choice of interchangeable condenser cartridges. Microflex cartridges give you superior Shure quality sound for every application. In addition, their programmable switches offer the flexibility to be set for Push to Talk, Push to Mute or Push On/Push Off modes. Attractively designed with a low profile, professional appearance, the Microflex Boundary microphones come with an easy to use paint mask for your custom-color installations.

The Shure MX391/O has an attached 12 ft (4 meter) cable terminated with a 4-pin mini connector and a separate preamplifier. A rubber strain relief is provided for applications where you want to remove the 4-pin mini connector and connect the microphone cable directly to screw terminals in the preamplifier.
Shure MX391/O Microflex Omnidirectional Boundary Microphone Black Omni
Shure MX391/O Microflex Omnidirectional Boundary Microphone Black Omni

collapse expand iconFeatures

  • Flat frequency response across the vocal range for uncolored sound
  • Interchangeable cardioid, supercardioid, and omnidirectional cartridges that provide optimal choice for each application
  • Sleek, low-profile design for unobtrusive appearance
  • Balanced, transformerless output for increased immunity to noise over long cable runs
  • Advanced RF filtering

collapse expand iconSpecs

  • Polar Pattern : Omnidirectional
  • Pickup angle: 360 degrees
  • Frequency Response: 50 to 17,000 Hz
  • Output Impedance (at 1000 Hz): 180 Ohms actual (rated at 150Ohms)
  • Open Circuit Sensitivity(1 kHz ref. 1 V per Pascal ): -21.5 dB (81.4 mV)
  • Maximum Sound Pressure Level (1 kHz at 1% Total Harmonic Distortion, 1 kOhm load): 110.7 dB (All settings +6 dB at 0 gain)
  • Signal to Noise Ratio (referenced at 94 dB SPL): 79.5 dB
  • Equivalent Output Noise (A-weighted): 14.5 dB SPL
  • Dynamic Range at 1 kOhm Load: 96.2 dB, 100 dB at 0 gain
  • Common Mode Rejection: 45 dB minimum, 10 Hz to 100 kHz
  • Preamplifier Output Clipping Level: -6 dBV (0.5 V), -12 dB at 0 gain
  • Polarity: Positive sound pressure on diaphragm produces positive voltage on pin
  • 2 relative to pin 3 of the preamplifier XLR output connector.
  • Power Requirements: 11 to 52 Vdc phantom, 2.0 mA current consumption
  • Environmental Requirements: Operating Temperature Range: ”18 degrees C to 57 degrees C (0 degree F to 135 degrees F); Relative Humidity: 0 to 95%
  • Dimensions (L x W x H): 3.1" x 2.08" x .750", (7.940 x 5.304 x 1.905 cm)
  • Furnished Accessories: Zippered bag, In-line Preamp, #4 hex wrench

collapse expand iconWarranty

One year warranty on wireless mics, mixers, and circuitry products.
2 year warranty on wired mics.
Warranty terms vary. Check with manufacturer for specific product warranty.

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