The Shure Beta 91A is designed for use with kick drums, as well as other traditional low-frequency applications including piano. Featuring an updated microphone capsule, integrated preamplifier, and XLR connection, Beta 91A offers a strong low-frequency response and is specifically tailored for bass frequency applications. The Beta 91A combines superior attack and punch for studio-quality sound, even at extremely high sound pressure levels (SPL).
Uniform half-cardioid polar pattern for maximum gain-before-feedback and rejection of off-axis sound
Precision-engineered low-profile design features integrated preamplifier and XLR connector to maximize setup efficiency while minimizing 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 maximize 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
Requires no external mounting or accessories for ease of use and storage
Furnished with zipper pouch
Type
Electret Condenser
Frequency Response
20 to 20,000 Hz
Polar Pattern
Half-cardioid (cardioid in hemisphere above mounting surface)
Impedance
146 Ohms
Sensitivity (at 1 kHz, open circuit voltage)
-48.5 dBV/Pa (3.8mV)
1 Pascal=94 dB SPL
Maximum SPL (1 kHz at 1% THD)
1000 Ohm load: 151 dB, 2500 Ohm load: 155 dB
Signal-to-Noise Ratio (referenced at 94 dB SPL at 1 kHz)
64 dB
S/N ratio is difference between 94 dB SPL and equivalent SPL of self noise, A-weighted
Dynamic Range (at 1 kHz)
1000 Ohm load: 121.5 dB
2500 Ohm load: 125.5 dB
Common Mode Rejection (20 Hz to 20 kHz)
> 55 dB
Clipping Level (20Hz-20 kHz at 1% THD)
1000 Ohm load: 7.50 dBV, 2500 Ohm load: 12.5 dBV
THD of microphone preamplifier when applied input signal is equivalent to cartridge output at specified SPL
Self Noise (typical, equivalent SPL, A-weighted)
29.5 dB SPL-A
Polarity
Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
Weight
Net: 470 g (16.6 oz.)
Frequency Contour Switch
7 dB of attenuation centered at 400 kHz
Connector
Three-pin professional audio (XLR), male, balanced
Power Requirements
11-52 Vdc phantom power, 5.6 mA
