Half-Cardioid Condenser Microphone

The Shure Beta Microphone Series 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 BETA91A combines superior attack and punch for studio-quality sound, even at extremely high sound pressure levels (SPL).

→ Premier live performance microphone with Shure quality, ruggedness, and reliability
→ Uniform half-cardioid polar pattern (in the hemisphere above mounting surface) for maximum gain before feedback and rejection of off-axis sound
→ Tailored frequency response for kick drums and bass-heavy instruments
→ Wide dynamic range for use in high SPL environments
→ Two-position contour switch enhances attack and clarity
→ Integrated preamp and XLR connector reduce stage clutter and provide a quick, secure setup
→ Low profile design requires no external mounting hardware
→ Steel grille and die-cast metal construction resist wear and abuse
→ Exceptional low-frequency reproduction
→ Extremely high SPL handling
→ High output level
→ No crossover distortion

Cartridge Type	Electret Condenser
Polar Pattern	Half-cardioid (cardioid in hemisphere above mounting surface)
Frequency Response	20 to 20,000 Hz
Output Impedance @ 1 kHz	146 O
Sensitivity open circuit voltage, @ 1 kHz, typical	–48.5 dBV/Pa[1] (3.8 mV)
Maximum SPL 1 kHz at 1% THD[2]	2500 O load 155 dB; 1000 O load 151 dB
Signal-to-Noise Ratio[3]	64.5 dB
Dynamic Range @ 1 kHz	2500 O load 125.5 dB; 1000 O load 121.5 dB
Clipping Level 20 Hz to 20 kHz, 1% THD	2500 O load 12.5 dBV; 1000 O load 7.5 dBV
Self Noise equivalent SPL, A-weighted, typical	29.5 dB SPL-A
Common Mode Rejection 20 Hz to 200 kHz	>_55 dB
Frequency Contour Switch	7 dB of attenuation centered at 400 kHz
Connector	Three-pin professional audio (XLR), male, balanced
Polarity	Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
Power Requirements	11–52 V DC[4] phantom power (IEC-61938), 5.4 mA
Net Weight	470 g (16.6 oz.)