Audio Technica U851A Cardioid condenser boundary microphone

Offering outstanding Audio-Technica sound for surface-mount applications, the U851A features a PivotPoint® rotating output connector, UniSteep® filter and UniGuard® RFI-shielding technology. This battery- or phantom-powered condenser microphone accepts interchangeable condenser elements - available for boundary microphones in cardioid, hypercardioid and omnidirectional polar patterns. Its heavy die-cast case and silicon foam bottom pads minimize coupling of surface vibration to the microphone. With superior off-axis rejection and maximum gain-before-feedback, this professional microphone sets audio-quality standards in challenging acoustic environments.

• Designed for surface-mount applications such as high-quality sound reinforcement, professional recording, television, conferencing and other demanding sound pickup situations
• PivotPoint® rotating output connector allows cable to exit from either the rear or the bottom of the microphone
• Superior off-axis rejection for maximum gain before feedback
• UniGuard® RFI-shielding technology offers outstanding rejection of radio frequency interference (RFI)
• UniSteep® filter provides a steep low-frequency attenuation to improve sound pickup without affecting voice quality
• Small-diameter UniPoint capsule near boundary eliminates phase distortion and delivers clear, high-output performance
• Heavy die-cast case and non-slip silicon foam bottom pads minimize coupling of surface vibration to the microphone
• Low-profile design with low-reflectance black finish for minimum visibility
• Operates on battery or phantom power

• Element: Fixed-charge back plate, permanently polarized condenser
• Polar Pattern: Half-cardioid (cardioid in hemisphere above mounting surface)
• Frequency Response: 30-20,000 Hz
• Low Frequency Roll Off: 80 Hz, 18 dB/octave
• Open Circuit Sensitivity: Phantom: -40 dB (10.0 mV) re 1V at 1 Pa Battery: -41 dB (8.9 mV) re 1V at 1 Pa
• Impedance: Phantom: 200 ohms Battery: 270 ohms
• Maximum Input Sound Level: Phantom: 133 dB SPL, 1 kHz at 1% T.H.D. Battery: 123 dB SPL, 1 kHz at 1% T.H.D.
• Dynamic Range: Phantom: 111 dB,1 kHz at Max SPL Battery: 101 dB, 1 kHz at Max SPL
• Signal to Noise Ratio: 72 dB, 1 kHz at 1 Pa
• Phantom Power Requiremens: 11-52V DC, 2 mA typical
• Battery Type: 1.5V AA/UM3
• Battery Current Life: 0.4 mA / 1200 hours typical (alkaline)
• Switch: Off, on-flat, on-roll-off
• Cable: 25.0' (7.6 m) long (permanently attached to microphone), 0.13" (3.2 mm) diameter, 2-conductor, shielded cable with TA3F-type connector
• Accessories: AT8531 power module; battery; soft protective pouch

A wide range condenser microphone with a cardioid polar pattern, the ultra-smart U891RCx is equipped with local or remote switching options. For flexible control in conference and boardroom installations, the unit's external contact closure ability allows a user to trigger an external device - a camera, for instance - from a switch on the microphone. Another ease-of-use feature: the microphone's electronic on-off switch can be set to three operating modes: touch-on/touch-off, press to talk, and press to mute. The mic is also equipped an 80 Hz low-cut UniSteep® filter to reduce pickup of low-frequency ambient noise. Its red LED status indicator can be controlled remotely. UniGuard® innovations offer unsurpassed immunity from radio frequency interference; interchangeable elements are available in cardioid, hypercardioid and omnidirectional polar patterns; a unique rotating PivotPoint® connector changes the cable exit point - no tools required. It requires 11 to 52V DC phantom power, which operates the microphone and switch circuitry.

• Designed for surface-mount applications such as high-quality sound reinforcement, conferencing, distance learning and other demanding sound pickup situations
• Ultra-quiet electronic switch can be set to any of three operating modes: "touch-on/touch-off," "touch-to-talk" and "touch-to-mute“
• External contact closure capability permits control of remote devices from microphone switch
• External LED control allows for accurate depiction of the live status of the microphone
• PivotPoint® rotating output connector allows cable to exit from either the rear or the bottom of the microphone
• Small-diameter UniPoint® capsule near boundary eliminates phase distortion and delivers clear, high-output performance
• UniGuard® RFI-shielding technology offers outstanding rejection of radio frequency interference (RFI)
• Heavy die-cast case and non-slip silicon foam bottom pads minimize coupling of surface vibration to the microphone
• Low-profile design with low-reflectance black finish for minimum visibility

• Element: Fixed-charge back plate, permanently polarized condenser
• Polar Pattern: Half-cardioid (cardioid in hemisphere above mounting surface)
• Frequency Response: 30-20,000 Hz
• Low Frequency Roll Off: 80 Hz, 18 dB/octave
• Open Circuit Sensitivity: 34 dB (19.9 mV) re 1V at 1 Pa
• Impedance: 200 ohms
• Maximum Input Sound Level: 130 dB SPL, 1 kHz at 1% T.H.D.
• Dynamic Range: 104 dB, 1 kHz at Max SPL
• Signal to Noise Ratio: 68 dB, 1 kHz at 1 Pa
• Phantom Power Requirements: 11-52V DC, 4 mA typical
• Weight: 266g
• Dimensions: 108.0mm long, 84.0mm maximum width, 23.0mm height
• Output Connector: TB5M-type
• Cable: 7.6m long, 3.2mm diameter, 5-conductor shielded cable (2 conductors under shield; 3 control wires outside shield); TA5F-type connector at microphone end, output end stripped and tinned for connection to electronic device

    Designed for Broadcast, House of Worship, Pro Music, and other applications.
    Half-cardioid polar pattern
    Boundary layer
    Ultra-thin profile (16 mm) housing
    Rubber non-slip bottom pad and strong steel screen
    Integrated pop filter

Case Material    Die cast zinc
Connector Type    3-pin XLR
Element    Back Electret Condenser
Finish    Non-reflecting Black
Finish    White
Impedance, Low-Z balanced    200 Ω
Mic Type    Boundary
Open Circuit Voltage    25 mV/Pascal
Polar Pattern    Cardioid
Wired/Wireless    Wired
Height    16 mm (0.63“)
Width    94 mm (3.7“)
Depth    123 mm (4.84“)
Weight Net    12.63 oz (358 g)

 SHURE MX-391/C Microphone BOUNDARY

Microflex Boundary There's never been smarter boundary microphones than the Microflex models from Shure. With many models to choose from, equipped with features like programmable, silent membrane switches, logic inputs and outputs, and LED indicators, Microflex Boundary microphones are the high-quality solution for a range of applications, such as altars, boardrooms and distance learning centers. Every Microflex Boundary microphone features one of the new interchangeable condenser cartridges. Available in cardioid, supercardioid and omnidirectional polar patterns, the Microflex cartridges give you superior Shure quality sound options for every installation. 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. Find out why we call the new Microflex Boundary microphones "the smart choice" for just about every application. Take a listen today.