Shure BETA 91A Boundary Kick Drum Microphone

The Shure Beta 91A is a boundary microphone that can double as a kick drum mic, as it can capture the punch and attack of low-frequency instruments such as kick (bass) drums. It features a wide frequency response well suited for capturing a variety of audio signals such as organ and piano. The flat, boundary design also aides in producing a strong, solid low-end response, as well as make it easy to mount inside of a bass drum. The Beta 91A is ideal for both recording and sound reinforcement alike.

Features
Uniform half-cardioid polar pattern for maximum gain-before-feedback and rejection of off-axis sound
Low-profile design features integrated preamplifier and XLR connector to facilitate setup efficiency while minimising stage clutter
Frequency response tailored for kick drum/low frequency applications with a wide dynamic range for use in high SPL environments
Two-position contour switch to maximise attack and clarity depending on application: select the flat response setting for natural sound in most applications or the Low-Mid Scoop setting for a strong low frequency punch with plenty of higher frequency attack
Furnished with zipper pouch
Specifications
Transducer Condenser (electret bias)
Polar Pattern Half-cardioid
Frequency Response 20 to 20,000 Hz
Output Impedance 146 Ohms
Sensitivity -48.5 dBV/Pa (3.8 mV)
Maximum SPL 2500-Ohm load: 155 dB (1 kHz at 1% THD)
1000-Ohm load: 151 dB (1 kHz at 1% THD)
Maximum Input Sound Level 20 Hz to 20 kHz, less than 1% THD
Signal-to-Noise Ratio 64.5 dB
Dynamic Range 2500-Ohm load: 125.5 dB (1 kHz at 1% THD)
1000-Ohm load: 121.5 dB (1 kHz at 1% THD)
Clipping Level 2500-Ohm load: 12.5 dBV
1000-Ohm load: 7.5 dBV
Self Noise (Equivalent SPL) 29.5 dB SPL (A-weighted)
Common Mode Rejection ≥55 dB (20 Hz to 200 kHz)
Switch Frequency Contour Switch: 7 dB of attenuation centred at 400 kHz
Power Requirements Phantom Power: 48 VDC +/- 4 Vdc (IEC-268-15/DIN 45 596), positive pins 2 and 3
Polarity Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
Power Requirements 11 to 52 VDC phantom power, 5.4 mA
Output Connectors 1 x XLR male, balanced
Dimensions 95.1 x 139.1 x 20.3 mm
Weight 470 g