Styled in white, this Shure MX391 is a Microflex omnidirectional boundary microphone. It's easy to use, features an inline preamp, and offers interchangeable mic capsules. It's designed to pick up speech in a manner preserving its intelligibility. The mic is well suited for sound reinforcement and recording applications in boardrooms, conference centers, educational settings, houses of worship, and more.
- The compact, low-profile microphone is designed to be surface-mounted on conference tables, stage floors, and lecterns.
- The sleek, unobtrusive form factor stays out of the way of panelists and presenters, making it a smart solution for video conferencing.
- The MX391 doesn't offer mute switches, so speakers can't mute themselves—the mic is always ready to capture every moment in a panel discussion or presentation.
- The condenser microphone is optimized for crisp, clear speech.
- The mic's omnidirectional pickup pattern captures sound from all around the mic, allowing more than one person to use a single microphone.
- An interchangeable mic capsule design allows you to swap out the omnidirectional capsule for a cardioid capsule (if you need a narrower pickup pattern) or a supercardioid capsule (for a very narrow pickup pattern).
- Included is an inline preamp with a standard 3-pin XLR output ready to plug into a PA system, mixer, or recorder capable of supplying 12 to 48V phantom power needed to power the mic.
- The preamp offers a high level of RF filtering, making the mic substantially less susceptible to unwanted radio interference.
Microphone
| Form Factor | Boundary/Surface Mount |
| Sound Field | Mono |
| Capsule | Electret Condenser |
| Polar Pattern | Omnidirectional |
| Circuitry | Solid-State |
| High-Pass Filter | None |
| Tone Adjustment | None |
| On-Board Controls | None |
| Windscreen | None |
Performance
| Frequency Range | 50 Hz to 17 kHz |
| Maximum SPL | 111 dB SPL |
| Impedance | 180 Ohms |
| Sensitivity | -22 dBV/Pa |
| Output Level | -6 dBV (Max) |
| Dynamic Range | 96.2 dB |
| Signal-to-Noise Ratio | 80 dB |
| Equivalent Noise Level | 15 dB A-Weighted |
| THD | 1% |
| CMRR | 45 dB |
Connectivity
| Output Connectors (Analog) | 1 x XLR 3-Pin Male (on Preamp) |
| Cable Length | 12.14' / 3.7 m |
Power
| Operating Voltage | 11 to 52 V (Phantom Power) |
| Operating Current Consumption | 2 mA |
Physical
| Color | White |
| Mounting | Surface-Mount |
| Operating Temperature | 0 to 135°F / -17.8 to 57.2°C |
| Operating Humidity | 0 to 95% |
| Storage Temperature | -20 to 165°F / -28 to 73°C |
| Certifications | CE, as per Manufacturer |
| Dimensions | H: 0.75 x W: 2.09 x L: 3.13" / H: 19.05 x W: 53.04 x L: 79.4 mm |
| Weight | 4.44 oz / 126 g |
